© 2013 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. The proceedings provide state-of-the-art scientific and engineering research findings and developments in the area of mobile robotics and assistive technologies. The proceedings collected together peer reviewed articles presented at the CLAWAR 2013 conference. It contains a strong showing of articles on legged locomotion with numbers of legs from two onwards. There is also a good collection of articles on systems that walls climbing, poles balancing, and other more complex structures following the traditional of CLAWAR themes. In addition, the proceedings also cover the subject of robot-human interaction, which focus on a more 'human' way of communicating with humanoid robots. As for human assistive devices, proceedings also cover exoskeletal and prosthetic devices, robots for personal and nursing cares to address the issues of ageing population in our society. Finally, the issue of the deployment of robots in society, it social and ethically consideration are also addressed in the proceedings.
Waldron, K. & Kinzel, G.L. 2003, Kinematics, Dynamics and Design of Machinery, 2nd, John Wiley and Sons, New York, USA.
Song, S-M & Waldron, KJ 1989, Machines that Walk The Adaptive Suspension Vehicle, MIT Press.
What is 16 feet long, 10 feet high, weighs 6,000 pounds, has six legs, and can sprint at 8 mph and step over a 4 foot wall? The Adaptive Suspension Vehicle (ASV) described in this book.
Waldron, KJ 2018, 'Bernard Roth: The early days of the design division at Stanford, and the beginnings of research in robotics', Mechanism and Machine Theory, vol. 125, pp. 45-51.View/Download from: UTS OPUS or Publisher's site
© 2017 This paper comprises a review of Bernard Roth's technical contributions and contributions to his professional community. Particular attention is paid to his role in the establishment of the unique design program of the Department of Mechanical Engineering at Stanford University. Another theme is the creation of one of the very first research programs in digitally controlled robotics in the Stanford Artificial Intelligence Laboratory. No review of Roth's career would be complete without touching on the numerous fundamental contributions to research in linkages and robotics. At the same time it is not possible in a work on this type to examine every one of his publications and other contributions. We have endeavored to select the most important, but that is, of course, a personal judgment.
Carmichael, MG, Liu, D & Waldron, KJ 2017, 'A framework for singularity-robust manipulator control during physical human-robot interaction', INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH, vol. 36, no. 5-7, pp. 861-876.View/Download from: UTS OPUS or Publisher's site
Waldron, KJ, Tran, TH & Madadnia, J 2010, 'Configuration design of a robotic vehicle for rough terrain mobility', International Journal of Intelligent Systems Technologies and Applications, vol. 8, no. 1-4, pp. 171-184.View/Download from: Publisher's site
In this paper, we describe the motivation for building a six-wheeled robotic vehicle with active suspension to test mobility improvement concepts on rough terrain. The vehicle is being designed and constructed as a final year class project in the School of Engineering and Information Technology of the University of Technology, Sydney. The configuration of the designed vehicle and the integration of the sensing and computation systems are described. © 2010 Inderscience Enterprises Ltd.
Waldron, KJ, Estremera, J, Csonka, PJ & Singh, SPN 2009, 'Analyzing Bounding and Galloping Using Simple Models', JOURNAL OF MECHANISMS AND ROBOTICS-TRANSACTIONS OF THE ASME, vol. 1, no. 1.View/Download from: Publisher's site
Estremera, J & Waldron, K 2008, 'Thrust Control, Stabilization and Energetics of a Quadruped Running Robot', The International Journal of Robotics Research, vol. 27, no. 10, pp. 1135-1151.View/Download from: UTS OPUS or Publisher's site
In order to achieve powered autonomous running robots it is essential to develop efficient actuator systems, especially for generating the radial thrust in the legs. In addition, the control of the radial thrust of the legs can be a simple, effective method for stabilizing the body pitch in a running gait. This paper presents the mechanical systems, models and control strategies employed to generate and control leg thrust in the KOLT quadruped running robot. An analytical model of the electro-pneumatic leg thrusting system is presented and analyzed to evaluate its performance and to facilitate the design of control strategies. Several experiments have been conducted to estimate the energy losses and determine their origins as well as to compute the energetic efficiency of the actuation system. Two thrust control methods are also proposed and tested experimentally. The closed loop method regulates thrust through the control of the hip liftoff speed, a conceptually simple control strategy that stabilizes the body pitch in pronk and trot gaits without the need for central feedback, even on irregular terrain. The open-loop control method regulates the energy added in each hop based on the model of the actuator system. The efficacy of these models and techniques is tested in several planar trot and pronk experiments, and the results are analyzed focusing on the body stabilization, the power consumption and the energetic efficiency.
Waldron, KJ & Abdallah, ME 2007, 'An optimal traction control scheme for off-road operation of robotic vehicles', IEEE-ASME TRANSACTIONS ON MECHATRONICS, vol. 12, no. 2, pp. 126-133.View/Download from: Publisher's site
Nichol, JG, Waldron, K, Singh, SP, Palmer, LR & Orin, DE 2004, 'System Design of a Quadrupedal Galloping Machine', International Journal of Robotics Research, vol. 23, no. 10-11, pp. 1013-1028.View/Download from: UTS OPUS or Publisher's site
In this paper we present the system design of a machine that we have constructed to study a quadrupedal gallop gait. The gallop gait is the preferred high-speed gait of most cursorial quadrupeds. To gallop, an animal must generate ballistic trajectories with characteristic strong impacts, coordinate leg movements with asymmetric footfall phasing, and effectively use compliant members, all the while maintaining dynamic stability. In this paper we seek to further understand the primary biological features necessary for galloping by building and testing a robotic quadruped similar in size to a large goat or antelope. These features include high-speed actuation, energy storage, on-line learning control, and high-performance attitude sensing. Because body dynamics are primarily influenced by the impulses delivered by the legs, the successful design and control of single leg energetics is a major focus of this work. The leg stores energy during flight by adding tension to a spring acting across an articulated knee. During stance, the spring energy is quickly released using a novel capstan design. As a precursor to quadruped control, two intelligent strategies have been developed for verification on a one-legged system. The Levenberg-Marquardt on-line learning method is applied to a simple heuristic controller and provides good control over height and forward velocity. Direct adaptive fuzzy control, which requires no system modeling but is more computationally expensive, exhibits better response. Using these techniques we have been successful in operating one leg at speeds necessary for a dynamic gallop of a machine of this scale. Another necessary component of quadruped locomotion is high-resolution and high-bandwidth attitude sensing. The large ground impact accelerations, which cause problems for any single traditional sensor, are overcome through the use of an inertial sensing approach using updates from optical sensors and vehicle kinematics
Vertechy, R., Castelli, V.P. & Waldron, K. 2004, 'Electro/Magneto-Sensitive Elastomers and Lagrangian Electro/Magneto-Statics', Chiang Mai Journal of Science, vol. 32, no. 3, pp. 287-292.View/Download from: UTS OPUS
Nichol, JG, Palmer, LR & Waldron, KJ 2004, 'Design of a leg system for quadruped gallop', Chinese Journal of Mechanical Engineering (English Edition), vol. 17, no. SUPPL., pp. 1-4.
Ohio State (OSU) and Stanford Universities are cooperating to understand quadruped galloping through the design of a self-contained, biomimetic, galloping robot. The leg for this quadruped was first designed at Ohio State University (OSU). A second-generation leg, with the same functional geometry, has been designed and tested at Stanford University. The objective of these tests was to determine that the single leg would be capable of prolonged operation at a velocity of 5 m/s, and that the control system, developed in simulation, would function under real-world conditions. The mechanical design of the quadruped is based on properties of biological quadruped animal legs. Important biomimetic design characteristics include minimal impact loss, elastic energy storage, and low inertia. The cable linkage, which works against a large spring to flex the knee, is uncoupled from the front-to-back hip actuator through a parallelogram-like cable mechanism. The controller developed for the leg is a direct adaptive fuzzy controller. The direct adaptive approach does not require system identification and can use heuristics to successfully control a complex system. With this controller, a single 2DOF leg constrained in yaw, pitch, roll and transverse translation can be successfully controlled. This controller was executed once each cycle at the top-of-flight. Parameters set by the controller were passed to PD controllers at each of the 2 joints: the hip and cable-actuated knee. The control of this leg required only 7 × 5 × 3 = 105 rules, each with a corresponding output for thigh and knee angle. This controller was implemented on an embedded processor attached to the leg. The leg reached a speed of 3 m/s. Modifications to the leg will increase this speed. The controller successfully adapted to the leg.
Marhefka, DW, Orin, DE, Schmiedeler, JP & Waldron, K 2003, 'Intelligent Control of Quadruped Gallops', IEEE - ASME Transactions on Mechatronics, vol. 8, no. 4, pp. 446-456.View/Download from: UTS OPUS or Publisher's site
In this paper, a new intelligent control approach for high-speed quadruped bounding and galloping gaits is presented. The controller is capable of learning the leg touchdown angles and leg thrusts required to track the desired running height and velocity of a quadruped in only one stride. Training of the controller is accomplished not with a mathematical model, but with simple rules based on a heuristic knowledge of the quadruped mechanics. The result is a controller that produces better velocity and height tracking characteristics than a Raibert-based controller and is robust to modeling errors. Additionally, by making use of the natural dynamics of the system, gait characteristics comparable to biological quadrupeds result. The status of a legged machine being constructed for demonstration of the control approach and further study of the characteristics of galloping is also presented.
Dev, P, Montgomery, K, Senger, S, Heinrichs, WL, Srivastava, S & Waldron, K 2002, 'Simulated Medical Learning Environments on the Internet', American Medical Informatics Association. Journal, vol. 9, pp. 437-447.View/Download from: Publisher's site
Learning anatomy and surgical procedures requires both a conceptual understanding of three-dimensional anatomy and a hands-on manipulation of tools and tissue. Such virtual resources are not available widely, are expensive, and may be culturally disallowed. Simulation technology, using high-performance computers and graphics, permits realistic real-time display of anatomy. Haptics technology supports the ability to probe and feel this virtual anatomy through the use of virtual tools. The Internet permits world-wide access to resources. We have brought together high-performance servers and high-bandwidth communication using the Next Generation Internet and complex bimanual haptics to simulate a tool-based learning environment for wide use. This article presents the technologic basis of this environment and some evaluation of its use in the gross anatomy course at Stanford University.
Stanley, C, Temkin, B, Dev, P, Heinrichs, WLR, Srivastava, S & Waldron, K 2001, 'Networked stereoscopic virtual environment system', Proceedings of the IEEE Symposium on Computer-Based Medical Systems, pp. 400-406.View/Download from: Publisher's site
Advanced collaborative display systems allow users to view a computing 'desktop' environment in a platform and location independent fashion. For real-time considerations, these systems become computationally very challenging, especially when video-streaming is included. The addition of stereoscopic video streaming is desirable in Virtual Environments (VE) created for the teaching of anatomy and surgery with real-time collaborative audio and video interactions at many locations. However this stresses the real-time requirements to the point at which realistic video is difficult to assure. For such a system to work, it is imperative that timing data be collected, analyzed, and understood. In this paper, we describe an experimental system designed primarily for collection of timing data required for robust collaborative medical training applications. The networked stereoscopic system uses a server-swappable multicast network protocol to stream real-time manipulations of 3D Virtual Body Structures (VBS) at th e server site to all clients participating in the multicast session. The three visual modes (mono, psa, and asi) have dynamic tuning parameters for adjusting the parallax and the focal point for the rendered scene, allowing users to define individual stereoscopic comfort zones. Our main result demonstrates that optimizing the graphics module is critical in achieving the necessary rendering rates. Different techniques of utilizing various memory resources increased the number of polygons rendered per second by over seven million. Depending on the type of memory used the number of polygons rendered per second varies from 2.25 to 9.12 million.
Dev, P, Heinrichs, WL, Srivastava, S, Montgomery, KN, Senger, S, Temkin, B, Hasser, C, Latombe, JC, Heegaard, J, Youngblood, P, Friedman, CP & Waldron, K 2001, 'Simulated learning environments in anatomy and surgery delivered via the next generation internet.', Medinfo. MEDINFO, vol. 10, no. Pt 2, pp. 1014-1018.
The Next Generation Internet (NGI) will provide high bandwidth, guaranteed Quality of Service, collaboration and security, features that are not available in today's Internet. Applications that take advantage of these features will need to build them into their pedagogic requirements. We present the Anatomy Workbench and the Surgery Workbench, two applications that require most of these features of the NGI. We used pedagogic need and NGI features to define a set of applications that would be difficult to operate on the current Internet, and that would require the features of the NGI. These applications require rich graphics and visualization, and extensive haptic interaction with biomechanical models that represent bony and soft tissue. We are in the process of implementing these applications, and some examples are presented here. An additional feature that we required was that the applications be scalable such that they could run on either on a low-end desktop device with minimal manipulation tools or on a fully outfitted high-end graphic computer with a realistic set of surgical tools. The Anatomy and Surgery Workbenches will be used to test the features of the NGI, and to show the importance of these new features for innovative educational applications.
Waldron, K & Hubert, C 2000, 'Control Of Contact Forces In Wheeled And Legged Off-road Vehicles', Experimental Robotics Vi, vol. 250, pp. 205-214.
The use of variable configuration vehicles creates the possibility of direct control of the contact forces between the foot or wheel of a vehicle and the ground. That control is an important element of the coordination of practical walking machines. Cont
Hung, MH, Orin, DE & Waldron, KJ 1999, 'Force distribution equations for general tree-structured robotic mechanisms with a mobile base', Proceedings - IEEE International Conference on Robotics and Automation, vol. 4, pp. 2711-2716.
An efficient formulation of the force distribution equations for actively-coordinated vehicles is presented. The applicable platforms include not only systems with star topologies, such as walking machines that have multiple legs with a single body, but also general tree-structured mechanisms, such as variably-configured wheeled vehicles having multiple modules. Based on this formulation, several standard optimization techniques, such as linear programming or quadratic programming, can be applied to obtain the solution. The efficiency of the formulation is demonstrated with results showing real-time execution on a Pentium PC.
Waldron, K 1999, 'Drafting A New Plan For Design', Mechanical Engineering, pp. 37-38.
Schmiedeler, JP & Waldron, K 1999, 'The Mechanics Of Quadrupedal Galloping And The Future Of Legged Vehicles', International Journal Of Robotics Research, vol. 18, no. 12, pp. 1224-1234.View/Download from: Publisher's site
Previous studies have noted that biological quadrupeds adjust their gaits when encountering drag in their locomotion. This paper investigates the hypothesis that these gait adjustments allow the legs to operate at an optimal working length when generatin
Sreenivasan, S & Waldron, K 1996, 'Displacement Analysis Of An Actively Articulated Wheeled Vehicle Configuration With Extensions To Motion Planning On Uneven Terrain', Journal Of Mechanical Design, vol. 118, no. 2, pp. 312-317.View/Download from: Publisher's site
This manuscript presents a displacement analysis of actively articulated wheeled vehicles on uneven terrain. These vehicles are distinct from traditional wheeled systems since they have the ability to actively adapt to variations in the terrain and they
Nanua, P & Waldron, K 1995, 'Energy Comparison Between Trot, Bound, And Gallop Using A Simple Model', Journal Of Biomechanical Engineering-transactions Of The ASME, vol. 117, no. 4, pp. 466-473.View/Download from: Publisher's site
In this paper, the dynamics of quadruped trot, gallop, and bound will be examined using a simple model for the quadruped. The body of the quadruped is modeled as a uniform bar and the legs are modeled by massless springs. It will be shown that symmetry c
Chung, W & Waldron, K 1995, 'An Integrated Control Strategy For Multifingered Systems', Journal Of Dynamic Systems Measurement And Control-transactions Of The ASME, vol. 117, no. 1, pp. 37-42.View/Download from: Publisher's site
A method of force allocation by optimizing the friction angles at finger contacts was combined with the computed torque method to find the torques to be commanded at finger joints for multifingered systems. In this way, slip can be avoided when the objec
The methods of reconstructing the applied wrench by using a six-axis force/torque sensor are discussed. Various types of contact, such as soft point and soft line contacts, are investigated. The ambiguity problem in reconstructing the wrench for soft poi
Waldron, K 1995, 'Terrain Adaptive Vehicles', Journal Of Mechanical Design, vol. 117, pp. 107-112.
Research on walking vehicles and variable configuration wheeled vehicles is reviewed. The central feature of the vehicles discussed is terrain adaptive capability. The principal elements of the technical problems of coordination and control are discussed
Husain, M & Waldron, KJ 1994, 'Direct position kinematics of the 3-1-1-1 stewart platforms', Journal of Mechanical Design, Transactions of the ASME, vol. 116, no. 4, pp. 1102-1107.View/Download from: Publisher's site
In this work, a closed form solution for the direct position kinematics problem of a special class of Stewart Platform is presented. This class of mechanisms has a general feature that the top platform is connected to the six limbs at four locations. Three limbs connect at one location and the remaining limbs connect to the top platform singly at three separate locations. The base platform is connected at six different locations as is the case in the general platform. This particular class of mechanism is termed as 3-1-1-1 mechanism in this paper. It has been shown that there are a maximum of sixteen real assembly configurations for the direct position kinematics problem. This has been verified using a geometric argument also. The numerical example solved in this paper demonstrates that it is possible to obtain a set of solutions which are all real. © 1994 by ASME.
Sreenivasan, S, Waldron, K & Nanua, P 1994, 'Closed-form Direct Displacement Analysis Of A 6-6 Stewart Platform', Mechanism And Machine Theory, vol. 29, no. 6, pp. 855-864.View/Download from: Publisher's site
The direct displacement analysis of a class of 6-6 Stewart platforms is considered here. Even though this is not the most general possible configuration, it has many of the advantages of the general configuration, and includes several useful arrangements
Murthy, V & Waldron, K 1992, 'Position Kinematics Of The Generalized Lobster Arm And Its Series-parallel Dual', Journal Of Mechanical Design, vol. 114, no. 3, pp. 406-413.View/Download from: Publisher's site
The generalized lobster arm is a six revolute open kinematic chain with 3 consecutive intersecting pairs of axes. A new solution of the inverse position kinematics problem of this arm which takes advantage of its specific geometry is presented. A compari
Gardner, JF, Srinivasan, K & Waldron, K 1990, 'A Solution For The Force Distribution Problem In Redundantly Actuated Closed Kinematic Chains', Journal Of Dynamic Systems Measurement And Control-transactions Of The ASME, vol. 112, no. 3, pp. 523-526.View/Download from: Publisher's site
Waldron, KJ, Raghavan, M & Roth, B 1989, 'Kinematics of a hybrid series-parallel manipulation system', Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME, vol. 111, no. 2, pp. 211-221.View/Download from: Publisher's site
In this paper we first derive the coordinate transformations associated with a threedegree-of-freedom in-parallel-actuated micro-manipulator. Then we combine these results with the transformations associated with an in-series three-axis wrist on which the in-parallel micro-manipulator is mounted. The results are the basic transformation equations between joint-space position variables and end-effector (or task space) position variables for a hybrid series/parallel six-degree-of-freedom manipulator system. This structural combination results in a manipulator which exhibits desirable fine and gross motion characteristics as both a stand-alone device or as a sub-system of a more complex system with redundant degrees of freedom. The forward and inverse position kinematics and rate and force decomposition for this hybrid six-degree-of-freedom linkage are presented. © 1989 ASME.
Pandy, M, Kumar, V, Berme, N & Waldron, K 1988, 'The Dynamics Of Quadrupedal Locomotion', Journal Of Biomechanical Engineering-transactions Of The ASME, vol. 110, no. 3, pp. 230-237.View/Download from: Publisher's site
Song, SM & Waldron, KJ 1987, 'GEOMETRIC DESIGN OF A WALKING MACHINE FOR OPTIMAL MOBILITY.', Journal of mechanisms, transmissions, and automation in design, vol. 109, no. 1, pp. 21-28.
The design of the geometry of a walking machine depends to a considerable extent on the applications for which the machine is intended. Nevertheless, there are some very general principles and approaches which may be applied. This paper deals with the geometric design of a hexapodal walking machine which is to prossess optimum mobility on varied terrain. This problem both illustrates, and serves as a vehicle for, the development of these general principles. Since one of the most important features of legged locomotion is the gait, the fundamental gaits of a 2N-legged (N greater than equivalent to 2) walking machine on both flat and irregular terrain are introduced first. The motion of the machine is assumed to be quasi-static. The mobility of a walking machine using these gaits, mainly centered on the hexapodal case, is then discussed.
Song, S & Waldron, K 1987, 'An Analytical Approach For Gait Study And Its Applications On Wave Gaits', International Journal Of Robotics Research, vol. 6, no. 2, pp. 60-71.View/Download from: Publisher's site
Song, S, Lee, J & Waldron, K 1987, 'Motion Study Of Two-dimensional And 3-dimensional Pantograph Mechanisms', Mechanism And Machine Theory, vol. 22, no. 4, pp. 321-331.View/Download from: Publisher's site
Wang, S & Waldron, K 1987, 'A Study Of The Singular Configurations Of Serial Manipulators', Journal Of Mechanisms Transmissions And Automation In Design-transactions Of The ASME, vol. 109, no. 1, pp. 14-20.View/Download from: Publisher's site
Vijaykumar, R, Waldron, K & Tsai, M 1986, 'Geometric Optimization Of Serial Chain Manipulator Structures For Working Volume And Dexterity', International Journal Of Robotics Research, vol. 5, no. 2, pp. 91-103.View/Download from: Publisher's site
Waldron, K, Vohnout, V, Pery, A & Mcghee, R 1984, 'Configuration-design Of The Adaptive Suspension Vehicle', International Journal Of Robotics Research, vol. 3, no. 2, pp. 37-48.View/Download from: Publisher's site
A new theory and a resulting algorithm for tracing the bounding surfaces of mechanical manipulator workspaces is presented. The natures of the numerous singular configurations and means of accommodating them within the algorithm are also studied. In order to sort surfaces of interest from the large number of possible solutions, a numerically implementable labelling technique is also presented. The algorithm is applicable to all practicable manipulator configurations with three, or more, degrees of freedom. © 1981 by ASME.
Kumar, A & Waldron, KJ 1980, 'DEXTROUS WORKSPACE.', American Society of Mechanical Engineers (Paper), no. 80 -DET-108.
The concept of a dextrous workspace, the space in which a manipulator hand can reach any point and rotate fully about any axis through that pont, is introduced. It is shown that the extrous workspace is bounded by surfaces generated by the algorithm presented in another paper. It is also demonstrated that classes of manipulator geometries possessing dextrous workspaces do exist.
Kumar, A & Waldron, KJ 1980, 'WORKSPACES OF A MECHANICAL MANIPULATOR.', American Society of Mechanical Engineers (Paper), no. 80 -DET-107.
A new theory and a resulting algorithm for tracing the bounding surfaces of mechanical manipulator workspaces is presented. The natures of the numerous singular configurations and means of accommodating them within the algorithm are also studied. In order to sort surfaces of interest from the large number of possible solutions, a numerically implementable labelling technique is also presented. The algorithm is applicable to all practicable manipulator configurations with three, or more, degrees of freedom.
Waldron, KJ & Sun, JWH 1979, 'CONTROL OF ANGULAR DISPLACEMENT IN BURMESTER SYNTHESIS PROBLEMS.', Urban Systems, vol. 1, pp. 38-41.
Methods of imposing inequality, or partial equality, constraints on the relative angular displacements of links of planar four-bar linkages synthesized using Burmester's technique have recently been developed as a result of the work of Filemon and of Waldron on the elimination of solutions requiring a change of branch. However, control of these relative displacements has many applications beyond elimination of branch change. The ability to impose inequality constraints on the angular displacements of any joint, or joints, opens a whole new class of synthesis problems. In this paper, a unified theory of the application of inequality constraints on joint angles is presented and illustrated with examples.
Waldron, KJ & Strong, RT 1978, 'Improved solutions of the branch and order problems of Burmester linkage synthesis', Mechanism and Machine Theory, vol. 13, no. 2, pp. 199-207.View/Download from: Publisher's site
A method is presented to resolve the ambiguity in Waldron's solution to the order problem of planar Burmester synthesis by inspection of an image pole circle. This replaces the more cumbersome method previously used. Another method is presented to allow the mapping of permissible segments of the circle-point curve, in Waldron's solution to the branch problem by inspection of the subscripts of the Qij, Tij and Uij points. This replaces the much more cumbersome angle sign table previously used. © 1978.
Waldron, KJ 1977, 'Graphical solution of the branch and order problems of linkage synthesis for multiply separated positions', Journal of Manufacturing Science and Engineering, Transactions of the ASME, vol. 99, no. 3, pp. 591-597.View/Download from: Publisher's site
The graphical solutions to the order and branch problems previously developed for the PP-P-P case are extended to cover all finitely separated, infinitesimally separated, and multiply separated four-bar Burmester synthesis problems. Two examples are given in detail: a P-P-P-P-P problem and a PP-P-P problem. © 1977 by ASME.
Waldron, KJ 1974, 'RANGE OF JOINT ROTATION IN PLANAR FOUR-BAR SYNTHESIS FOR FINITELY SEPARATED POSITIONS - 2. ELIMINATION OF UNWANTED GRASHOF CONFIGURATIONS.', American Society of Mechanical Engineers (Paper), no. 74 -DET-109.
The methods given in Part 1 and by K. H. Modler are used to eliminate choices of circle points which cannot give a solution linkage of given Grashof class. It is assumed here that no means of ensuring a solution of the given class is available and that trial and error will be used. The techniques presented reduce the amount of trial and error needed.
Waldron, KJ 1973, 'A study of overconstrained linkage geometry by solution of closure equations - Part 1. Method of study', Mechanism and Machine Theory, vol. 8, no. 1, pp. 95-104.View/Download from: Publisher's site
A method is described which enables all constrained linkages with given numbers and types of joints and with no passive degrees of freedom, to be derived. This method is based on the dependence of the linkage closure equations in overconstrained linkages. It is applied to a class of linkages in Part 2 of this work, which follows in a later issue. © 1973.
A method of relating the geometry of contacting surfaces to motion capability in the joints of spatial linkages is presented. Ball's screw system and reciprocal screw system are used to provide this relationship which is then converted into algebraic form. A differential equation which must be satisfied by the surface at points of contact is derived and used to prove several theorems relating to contact geometry. © 1972.
A general method for the determination of the mobility of any rigid body mechanism is derived using Ball's theory of the instantaneous screw axis. The classical mobility equations are related to this method and their limitations are elucidated. A relationship between the reciprocal screw systems of the joints of a mechanism and the number of accurate operations required in the manufacture of a machine based on that mechanism is described. © 1966.
© 2013, Springer International Publishing Switzerland. Supporting the design process for running biped robots, analytical models are presented for two aspects of running: the duty factor (DF) of the gait, and the stiffness value of the leg. For a given running speed, an optimal DF exists that minimizes the energy expenditure. We present a formula for the optimal DF based on a model of the energetics, and the results are compared to both human data and simulation results. In addition, a model is presented for the stiffness value of the leg as a function of the physical properties, speed, and DF. The Gait Resonance Point is proposed as a design target for compliant running. At this point, the gait matches the spring resonance and the stiffness value becomes independent of the DF.
Waldron, K 2013, 'My Professional Career: a Summary' in Kumar, V, Sreenivasan, SV & Schmiedeler, J (eds), Advances in Mechanisms, Robotics, and Design Education and Research, Springer, New York, pp. VII-XIX.View/Download from: UTS OPUS
In 1964 I was studying for the degree of Master of Engineering Science in the
Department of Mechanical Engineering of the University of Sydney. This was a
course work plus thesis master's degree. I took a class from Associate Professor
Jack Phillips on kinematics of mechanisms. Like many others before, and since, I
was fascinated by the proposition that one could predict the movability of an assemblage
of rigid links connected by joints by simply counting the numbers of members
and joints, and noting the number of degrees of freedom of each joint. I was further
fascinated to learn that there were anomalous mechanisms that had more mobility
than predicted by the constraint criteria. I wrote up some ideas that really amounted
to treating each closure separately. Abe Soni had recently published a paper about
constraint analysis in ASME Transactions, I think it would have been J. Engineering
for Industry. In those days journals published discussions on the papers they published.
Ken Hunt came to visit Jack in this time frame, so the three of us wrote a
discussion on Abe's paper. That was my introduction to research in this technical
area. At Ken's suggestion I contacted Bernie Roth, and a couple of others in the
U.S. about doing a Ph.D. Bernie came up with a Research Assistantship, so I took
myself off to Stanford in the middle of 1965
Waldron, MB & Waldron, KJ 2013, 'Design for Inclusivity: Meaningful Collaboration with Differences' in Kumar, V, Schmiedler, J & Sreenivasan, SV (eds), Advances in Mechanisms, Robotics, and Design Education and Research, Springer, pp. 1-16.View/Download from: UTS OPUS or Publisher's site
The ubiquitous availability of the internet for global networking has
made collaborating by differences necessary. This is challenging because of the
human history of tribal organizations. In this paper we draw from our 45 years
of personal and professional journey together to elicit the skills that have helped
us to successfully engage across racial, cultural, and academic differences. It
required designing new rules of social and academic engagement that changed
how we related with the 'other'. We rely on these techniques daily to inform us
on how to facilitate collaboration in any situation capitalizing on the diversity of
thought, body, experience, belief, and/or training while focusing on the similarity
of our journey.
Waldron, K, Ward, P, Liu, DK & Waldron, KJ 2013, 'Optimal Design of a Magnetic Adhesion System for Climbing Robots' in Waldron, KJ & Tokhi, MO (eds), Nature-Inspired Mobile Robotics, World Scientific Publishing, Singapore, pp. 375-382.View/Download from: UTS OPUS
© 2011, Springer Science+Business Media B.V. Many of the important developments in mechanism and machine science of the past 50 years originated with work in the USA. In this chapter we will attempt to review the most significant of these. Space is limited, so some valuable topics cannot be addressed.
Csonka, PJ & Waldron, KJ 2010, 'Static and dynamic maneuvers with a tendon-coupled biped robot' in CISM International Centre for Mechanical Sciences, Courses and Lectures, pp. 265-272.View/Download from: Publisher's site
© 2010, CISM, Udine. Bipedal robots have generally either been designed for static motions or dynamic maneuvers, but the ability for operation in the real world in both realms is becoming increasingly relevant. In this work we explain the abilities of a human scale bipedal robot with tendon-coupled knee and ankle joints that is able to balance, step, hop and run several steps in a two dimensional plane.
Waldron, K 2010, 'Contributions to MMS and IFToMM from USA' in Ceccarelli, M (ed), Role of MMS and IFToMM in Technology Development, Springer, pp. 459-476.
Waldron, K & Csonka, PJ 2010, 'A brief history of legged robotics' in Ceccarelli, M (ed), Role of MMS and IFToMM in Technology Development, Springer, pp. 59-72.
Waldron, K & Schmiedler, J 2008, 'Chapter 1, Kinematics' in Siciliano, B & Khatib, O (eds), Handbook of Robotics, Springer, pp. 1-26.
Khonasty, R, Carmichael, MG, Liu, D & Waldron, K 2017, 'Upper Body Pose Estimation Utilizing Kinematic Constraints from Physical Human-Robot Interaction', Australasian Conference on Robotics and Automation 2017, Australasian Conference on Robotics and Automation, ARAA, Sydney Australia, pp. 1-10.View/Download from: UTS OPUS
In physical Human-Robot Interaction (pHRI),
knowing the pose of the operator is beneficial
and may allow the robot to better accommodate
the human operator. Due to a
large redundancy in the human body, determining
the pose of the human operator is difficult
to achieve in unstructured environments
especially in human-robot collaborative operations
where the robot often occludes the human
from vision-based sensors. This work presents
an upper body pose estimation method based
on exploiting known positions of the human operator's
hands while performing a task with the
robot. Upper body pose is estimated using upper
limb kinematic models alongside sensor information
and model approximations to produce
solutions that are biomechanically feasible.
The pose estimation method was compared
to upper body poses obtained using a motion
capture system. It was shown to be able to
perform robustly with varying amounts of available
information. This approach is well suited
in applications where robots are controlled using
well-defined interfaces such as handlebars,
operating in unstructured environments.
Reeks, C, Carmichael, M, Liu, D & Waldron, K 2016, 'Angled sensor configuration capable of measuring tri-axial forces for pHRI', Proceedings - IEEE International Conference on Robotics and Automation, IEEE International Conference on Robotics and Automation, IEEE, Stockholm, Sweden, pp. 3089-3094.View/Download from: UTS OPUS or Publisher's site
This paper presents a new configuration for single axis tactile sensor arrays molded in rubber to enable tri-axial force measurement. The configuration requires the sensing axis of each sensor in the array to be rotated out of alignment with respect to external forces. This angled sensor array measures shear forces along axes in a way that is different to a planar sensor array. Three sensors using the angled configuration (22.5°, 45° and 67.5°) and a fourth sensor using the planar configuration (0°) have been fabricated for experimental comparison. Artificial neural networks were trained to interpret the external force applied along each axis (X, Y and Z) from raw pressure sensor values. The results show that the angled sensor configuration is capable of measuring tri-axial external forces with a root mean squared error of 1.79N, less error in comparison to the equivalent sensor utilizing the planar configuration (4.52N). The sensors are then implemented to control a robotic arm. Preliminary findings show angled sensor arrays to be a viable alternative to planar sensor arrays for shear force measurement; this has wide applications in physical Human Robot Interaction (pHRI).
Bykerk, L, Liu, D & Waldron, K 2016, 'A Topology Optimisation Based Design of a Compliant Gripper for Grasping Objects with Irregular Shapes', 2016 IEEE International Conference on Advanced Intelligent Mechatronics (AIM), IEEE/ASME International Conference on Advanced Intelligent Mechatronics, IEEE, Banff, Canada.View/Download from: UTS OPUS or Publisher's site
Complex steel structures such as power transmis-
sion towers require regular inspection and maintenance during
their lifetime. This work is currently completed by teams of
human workers who climb the live structures. The exposure
of these workers to the risks of climbing and completing
work on towers provides motivation for developing a robotic
substitute. There are many complex elements of climbing power
transmission towers, such as the variation in beam shapes,
sizes and orientations. To the best of our knowledge, there
is no existing robotic grasping solution that can be directly
used in this complex environment. This paper presents a
topology optimisation based design of a compliant gripper
for grasping objects with irregular shapes such as the beam
members found in power transmission towers. The structure of
the gripper is obtained through the use of a modified topology
optimisation model where stiffness constraints are implemented
in the optimisation to increase the strength of the gripper in
desired areas. The stiffness constrained topology optimisation
produces a novel gripper design which is validated through both
simulations and physical testing of the manufactured gripper
on a variety of physical objects.
Waldron, K 2014, 'A Study of the Complete Stride Cycle in dynamically Stable Quadrupedal Locomotion', Mobile Service Robotics, International Conference on Climbing and Walking Robots (CLAWAR), World Scientific, Poznan, Poland, pp. 223-230.View/Download from: Publisher's site
An understanding of the gross mechanics of running is essential for the design of running robots that use dynamically stable gaits. In earlier papers [1, 2] the author and his colleagues analyzed the complete stride cycle for both transverse and rotary gallops. This resulted in a solution that required that the durations of the two flight phases should be equal, in both cases. Examination of experimental results indicates that this conclusion is quite wrong. Review of the analysis indicates that this result was driven by an assumption that the system behaves as a rigid body for motion about the roll axis. Abandoning that assumption produces a simpler analysis which produces results that are broadly consistent with available experimental data.
Liu, DK, Dissanayake, G, Valls Miro, J & Waldron, KJ 2014, 'Infrastructure robotics: Research challenges and opportunities', 31st International Symposium on Automation and Robotics in Construction and Mining, ISARC 2014 - Proceedings, International Symposium on Automation and Robotics in Construction, ISARC, Sydney, Australia, pp. 43-49.View/Download from: UTS OPUS or Publisher's site
Infrastructure robotics is about research on and development of methodologies that enable robotic systems to be used in civil infrastructure inspection, maintenance and rehabilitation. This paper briefly discusses the current research challenges and opportunities in infrastructure robotics, and presents a review of the research activities and projects in this field at the Centre for Autonomous Systems, University of Technology Sydney.
Waldron, KJ, Tokhi, MO & Virk, GS 2013, 'Preface', Nature-Inspired Mobile Robotics: Proceedings of the 16th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, CLAWAR 2013.
Jacobs, DA, Park, LJ & Waldron, KJ 2013, 'An actuated continuous spring loaded inverted pendulum (SLIP) model for the analysis of bouncing gaits', International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, World Scientific Publishing, pp. 463-470.View/Download from: Publisher's site
© 2013 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. The Spring Loaded Inverted Pendulum (SLIP) model is a simple model for analyzing bouncing type legged gaits such as hopping and running. Reducing the full system dynamics allows for simplified analysis of major characteristics of locomotion for a wide variety of systems. However, the implementation of the SLIP model in the design and control of robotic locomotion can benefit from including more representative stance and flight dynamics. For example, in the SLIP model, the stance dynamics are fully conservative. However, physical systems will exhibit energy loss as a consequence of ground contact and will also do negative work through friction and actuator losses. To recover this lost work, the stance phase must be asymmetric and must include a thrusting portion. An actuated form of the SLIP model with fully continuous flight and stance dynamics is presented to analyze the stability space presented by the original SLIP model. The combined dynamic and control system stability is analyzed in the return map method and the simulated results show that heuristic control of the leg angle can stabilize the hopping gait only under certain circumstances.
Lozano, A, Peters, G, Liu, D & Waldron, K 2011, 'Study of Ant Locomotion in Surface Transitions for Climbing Robot Design', Field robotics : proceedings of the 14th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, International Conference on Climbing and Walking Robots (CLAWAR), World Scientific, Paris, France, pp. 173-180.View/Download from: UTS OPUS or Publisher's site
Many climbing robots designed based on simple representations of the arthropod body have proven to be able to move on relatively flat surfaces and simple environments. However these robots are not able to navigate in complex environments such as steel bridges. This paper presents experimental studies on ant locomotion, particularly focusing on ant leg gait and posture when traversing a variety of complex surfaces, with the aim of providing climbing robot designers a better understanding of biological ant locomotion through a complex terrain.
Pagano, D, Liu, D & Waldron, K 2012, 'A Method for Optimal Design of an Inchworm Climbing Robot', Proceedings of the 2012 IEEE International Conference on Robotics and Biomimetics, IEEE International Conference on Robotics and Biomimetics, IEEE, Guangzhou, China, pp. 1293-1298.View/Download from: UTS OPUS or Publisher's site
Many ferromagnetic structures require regular inspection and maintenance to ensure their longevity, structural integrity and aesthetics. These operations are often very hazardous to workers, as they are normally performed at height or in confined spaces, and can expose workers to hazardous materials such as lead based paints and vehicle fumes. An inchworm climbing robot has been proposed as a solution that would improve the quality of the inspection procedure and the occupational health and safety for the maintenance personnel while reducing setup times and costs. However, a number of challenges in designing such an inchworm robot arise from the environmental, mobility and safety factors. This paper describes these challenges for given design applications and presents a method to optimise the design to address the challenges. Analyses of the results attest to the feasibility of the solution.
Madadnia, J, Waldron, K, Waldron, M & Koosha, H 2011, 'Design for Innovation and Design for Performance Two Case Studies on Project-Based-Design', Proceedings of the 4th ICMEM, International Conference on Mechanical Engineering and Mechanics, Science Press USA Inc, Suzhou, China, pp. 105-109.View/Download from: UTS OPUS
Two case studies on 'Design for Innovation (DFI)' and 'Design for Performance (DFP)' are outlined in the project based learning (PBL) in the Engineering Design subject (48670) at University of technology Sydney (UTS). Projects are real-life and focus on 'Innovation' or 'Performance'.
Csonka, PJ, Perkins, A & Waldron, K 2010, 'Passively stable hopping of an articulated leg with a tendon-coupled ankle', Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems, International Conference on Intelligent Robots and Systems, IEEE, Taipei, Taiwan, pp. 3629-3633.View/Download from: UTS OPUS or Publisher's site
Dynamic maneuvers have been successfully implemented on many prismatic legged robots. Systems with articulated legs of significant relative mass pose more of a challenge in part due to the physics of thrusting with rotating limbs, which results in undesi
Perkins, AD & Waldron, KJ 2009, 'HEURISTIC CONTROL OF BIPEDAL RUNNING: STEADY-STATE AND ACCELERATED', MOBILE ROBOTICS-SOLUTIONS AND CHALLENGES, 12th International Conference on Climbing and Walking Robots the Support Technologies for Mobile Machines (CLAWAR), WORLD SCIENTIFIC PUBL CO PTE LTD, Istanbul, TURKEY, pp. 575-582.View/Download from: Publisher's site
Carmichael, MG, Liu, D & Waldron, K 2010, 'Investigation of Reducing Fatigue and Musculoskeletal Disorder with Passive Actuators', Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Taipei, Taiwan, pp. 2481-2486.View/Download from: UTS OPUS or Publisher's site
Robotic systems such as exoskeletons can be effectively used in the reduction of fatigue and musculoskeletal disorders (MSD) associated with physical tasks, but robots which work in physical contact with humans pose problems with user safety. A novel approach to developing intrinsically safe robots is to use passive actuators which have the advantage of being safer, ensuring stability, high force/weight ratios and lower power consumption. It is however not clear how effective an exoskeleton utilizing passive actuators would be in reducing fatigue and the risk of MSD. This paper analyzes the benefit of using such a system with results from dynamic simulations and an experiment using a specially designed mechanism used for evaluation. Results indicate that fatigue and effort could be reduced if robot impedance is minimized. Experiments also highlighted issues of implementing such a system into practice.
Peters, G, Pagano, D, Liu, D & Waldron, K 2010, 'A prototype climbing robot for inspection of complex ferrous structures', Proceedings of the 13th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines (CLAWAR'2010), International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, World Scientific, Nagoya, Japan, pp. 150-156.View/Download from: UTS OPUS
Currently many hazardous maintenance and inspection tasks, such as paint inspection and corrosion condition monitoring of steel structures, are being performed manually by workers, which causes serious health and safety problems. This paper presents a concept climbing robot, with the aim of exploring highly complex ferrous structures such as steel bridges, for the purpose of inspection duties. To demonstrate this concept, a quadruped prototype is developed. A modular architecture that simplifies the development process and improves reusability has been implemented. Permanent magnet compliant pads on each foot provide a simple method of adhesion on the highly complex and unsmooth surface of a bridge. A simple detachment mechanism has been employed. Experiments have been conducted to prove the concept and test the design of the prototype.
Jacobs, DA & Waldron, KJ 2008, 'A nonlinear model for simulating contact and collision', Advances in Mobile Robotics - Proceedings of the 11th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, CLAWAR 2008, pp. 930-936.
Collision and contact are complex interactions vital to the analysis of several research fields. In many models, collision and contact are unable to be described by a single equation because the change in energy loss is related to the relative collision velocity of the two objects. In this paper, an improvement is made to an existing nonlinear model to increase the realism of simulations of collision and contact. The new formulation removes the inconsistencies and numerical instability of previous treatments while maintaining the computational simplicity of the original model. Given a set of coefficient of restitution data, the new model simulates realistic collision behavior across a wide range of velocities. The new model is compared to two previous formulations in their ability to simulate experimental data from a croquet ball colliding with a croquet mallet in the normal direction. Copyright © 2008 by World Scientific Publishing Co. Pte. Ltd.
Abdallah, ME & Waldron, KJ 2007, 'Stiffness and Duty Factor Models for the Design of Running Bipeds', ADVANCES IN CLIMBING AND WALKING ROBOTS, PROCEEDINGS, 10th International Conference on Climbing and Walking Robots (CLAWAR 2007), WORLD SCIENTIFIC PUBL CO PTE LTD, Singapore, SINGAPORE, pp. 329-339.View/Download from: Publisher's site
Estremera, J & Waldron, K 2006, 'Leg Thrust Control for Stabilization of Dynamic Gaits in a Quadruped Robot', Proceedings of ROMANSY 2006, Warsaw, Poland, pp. 213-220.
Enedah, C.C. & Waldron, K. 2006, 'Robotic Perception of Mechanical Properties of the Human Skin: A Validation Study', Medicine Meets Virtual Reality 14, Medicine Meets Virtual Reality, Long Beach, CA.
Vertechy, R., Castelli, V.P. & Waldron, K. 2006, 'On the Driving Circuits of Electro-Sensitive Elastomers', Proceedings of Actuator 2006, Actuator 2006, Actuator 2006, Bremen, Germany, pp. 1-4.View/Download from: UTS OPUS
In the last decade, Electro-Sensitive Elastomers (ESE) with significant electro-mechanical response have been discovered. These polymers are the candidate materials for the construction of solid-state actuators and sensors. To date, devices made by ESE show performances rather below expectations. This paper addresses the dynamic performance of ESE. Experimental and simulation results are presented which show that the response of ESE can be enhanced if they are activated by proper energy sources and strategies. In particular, better results are achieved by overdriving the ESE by a capacitor charging pulsed power source.
Waldron, K. & Nichol, J.G. 2004, 'Architectural Issues in Running Machines', Proceedings of ROMANSY 15, Montreal, Canada.
Waldron, K & Kallem, V 2004, 'Control Modes for a Three-Dimensional Galloping Machine', Proceedings of DETC 2004: the 28th Biennial Mechanisms and Robotics Conference, International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, ASME, Salt Lake City, USA, pp. 1525-1533.View/Download from: UTS OPUS or Publisher's site
A set of relationships are developed to estimate the effects of control inputs on different axes of a galloping machine. It is demonstrated that control must be approached on a stride cycle basis to avoid serious cross-coupling between degrees of freedom. It is also demonstrated that a somewhat different approach to the Raibert controller is necessary for galloping. The relationships developed are primarily useful to estimate sensitivities to different control approaches, and thereby develop useful design information. Their use is illustrated by calculating sensitivities for our KOLT galloping vehicle.
Nichol, JG, Palmer, LR & Waldron, K 2004, 'Design of a Leg System for Quadruped Gallop', Proceedings of the 11th World Congress in Mechanism and Machine Science, IFToMM World Congress, China Machine Press, Tianjin, China, pp. 87-91.View/Download from: UTS OPUS
Ohio State (OSU) and Stanford Universities are cooperating to understand quadruped galloping through the design of a self-contained, biomimetic, galloping robot. The leg for this quadruped was first designed at Ohio State University (OSU). A second-generation leg, with the same functional geometry, has been designed and tested at Stanford University. The objective of these tests was to determine that the single leg would be capable of prolonged operation at a velocity of 5m/s, and that the control system, developed in simulation, would function under real-world conditions. The mechanical design of the quadruped is based on properties of biological quadruped animal legs. Important biomimetic design characteristics include minimal impact loss, elastic energy storage, and low inertia. The cable linkage, which works against a large spring to flex the knee, is uncoupled from the front-to-back hip actuator through a parallelogram-like cable mechanism. The controller developed for the leg is a direct adaptive fuzzy controller. The direct adaptive approach does not require system identification and can use heuristics to successfully control a complex system. With this controller, a single 2DOF leg constrained in yaw, pitch, roll and transverse translation can be successfully con-trolled. This controller was executed once each cycle at the top-of-flight. Parameters set by the controller were passed to PD controllers at each of the 2 joints: the hip and cable-actuated knee. The control of this leg required only 7×5×3 = 105 rules, each with a corresponding output for thigh and knee angle. This controller was implemented on an embedded processor attached to the leg. The leg reached a speed of 3 m/s. Modifications to the leg will increase this speed. The controller successfully adapted to the leg
Waldron, K, Arkin, RC, Bakkum, D, Merrill, E & Abdullah, MF 2003, 'Proprioceptive Control for a Robotic Vehicle Over Geometric Obstacles', Proceedings of the 2003 IEEE International Conference on Robotics and Automation - Vol 1, IEEE International Conference on Robots and Automation, IEEE, Taipei, Taiwan, pp. 109-114.View/Download from: UTS OPUS
In this paper we describe a software system built to coordinate an autonomous vehicle with variable configuration ability operating in rough terrain conditions. The paper describes the system architecture, with an emphasis on the action planning function. This is intended to work with a proprioceptive algorithm that continuously coordinates wheel torques and suspension forces and positions to achieve optimal terrain crossing performance.
Palmer, LR, Orin, DE, Marhefka, DW, Schmiedeler, JP & Waldron, K 2003, 'Intelligent Control of an Experimental Articulated Leg for a Galloping Machine', Proceedings of the 2003 IEEE International Conference on Robotics and Automation - vol 3, IEEE International Conference on Robots and Automation, IEEE, Taipei, Taiwan, pp. 3821-3827.View/Download from: UTS OPUS or Publisher's site
Intelligent controllers are being used with increasing effectiveness on complex systems. This work verifies the effectiveness of fuzzy control, an intelligent method, on a single, articulated-leg that was designed to be used on a high-speed galloping quadruped. Intelligent methods are compared to other control methods in simulation and on the OSU DASH (Dynamic Articulated Structure for High-performance) leg. It is shown that the intelligent controllers outperform non-learning methods. Using fuzzy control, the OSU DASH leg performs stable hopping on a treadmill moving at 2.0 m/s.
Thornhill, LD, Walls, A, Arkin, RC, Beno, JH, Bergh, C, Bresie, D, Giovannetti, A, Gothard, BM, Matthies, LH, Nogueiro, P, Scanlon, J, Scott, R, Simon, M, Smith, W & Waldron, K 2003, 'Design of an agile unmanned combat vehicle: a product of the DARPA UGCV program', Unmanned Ground Vehicle Technology V. Proceedings of the SPIE., Unmanned Ground Vehicle Technology V, SPIE, Orlando, USA, pp. 358-370.View/Download from: UTS OPUS or Publisher's site
The unmanned ground combat vehicle (UGCV) design evolved by the SAIC team on the DARPA UGCV Program is summarized in this paper. This UGCV design provides exceptional performance against all of the program metrics and incorporates key attributes essential for high performance robotic combat vehicles. This performance includes protection against 7.62 mm threats, C130 and CH47 transportability, and the ability to accept several relevant weapons payloads, as well as advanced sensors and perception algorithms evolving from the PerceptOR program. The UGCV design incorporates a combination of technologies and design features, carefully selected through detailed trade studies, which provide optimum performance against mobility, payload, and endurance goals without sacrificing transportability, survivability, or life cycle cost. The design was optimized to maximize performance against all Category I metrics. In each case, the performance of this design was validated with detailed simulations, indicating that the vehicle exceeded the Category I metrics. Mobility metrics were analyzed using high fidelity VisualNastran vehicle models, which incorporate the suspension control algorithms and controller cycles times. DADS/Easy 5 3-D models and ADAMS simulations were also used to validate vehicle dynamics and control algorithms during obstacle negotiation.
Waldron, K. 2002, 'Near Optimal Coordination of Legged Vehicles Over Large Obstacles', Proceedings of ARK 2002, pp. 501-515.
Nichol, JG & Waldron, K 2002, 'Biomimetic Leg Design for Untethered Quadruped Gallop', Proceedings of the 5th International Conference on Climbing and Walking Robots and the Support for Mobile Technologies (CLAWAR), International Conference on Climbing and Walking Robots and the Support for Mobile Technologies, Professional Engineering Publishing, Paris, France, pp. 49-54.View/Download from: UTS OPUS
Although there has been considerable work on artificial implementations of dynamic legged locomotion using various gaits, there has been little work on the gallop gaits. Ohio State (OSU) and Stanford Universities are cooperating to understand quadrupedal galloping through the design of a self-contained, biomimetic, galloping robot. The mechanical design of this machine is based on measurements of several quadrupedal animals, most notably the domestic goat (Capra).
Dev, P, Heinrichs, WL, Srivastava, S, Montgomery, KN, Senger, S, Temkin, B, Hasser, C, Latombe, JC, Heegaard, J, Youngblood, P, Friedman, CP & Waldron, K 2001, 'Simulated Learning Environments in Anatomy and Surgery Delivered via the Next Generation Internet', Proceedings of MedInfo 2001, World Congress on Medical Informatics, London, UK.
Terrain adaptive wheeled vehicles offer great promise for locomotion on rugged terrain. In order to properly design terrain adaptive vehicles or control schemes for such vehicles, one needs an effective simulator. Many simulators are based on detailed dynamic analysis. Featherstone's method of articulated inertias makes such dynamic simulators reasonably efficient. However, rover vehicles often operate at low speeds that make the dynamic analysis unnecessary. A simpler approach is to use only velocity and position information to obtain the next state. Simulation on rugged terrain requires the program to account for gravitational and contact forces. An algorithm using potential energy methods is proposed as an alternate rough terrain simulator. © 1998 American Society of Civil Engineers.
Chung, WY & Waldron, KJ 1994, 'Simulation of dexterous manipulation for multifingered systems', Proceedings - IEEE International Conference on Robotics and Automation, pp. 2321-2326.
Combined grasping and manipulation by multifingered hands was studied. A method of force allocation by optimizing the friction angles at finger contacts was combined with the computed torque method to find the torques to be commanded at finger joints for multifingered systems. In this way, the chance of slip can be minimized when the object is grasped or manipulated. A rolling motion between the grasped object and the fingertips was studied in simulation. A history-based method was proposed to improve the smoothness of the input torque commands, and force feedback was used to compensate for the uncertainty of the system. Any finger which moved beyond the boundaries of its working volume was also moved to a new position for regrasping. The proposed method can be efficiently used to find the necessary actuator torques, and is applicable for real-time application. Three dimensional simulation results are given in this paper.
Bawab, S, Kinzel, GL & Waldron, KJ 1994, 'Rectified synthesis of six-bar mechanisms with well defined transmission angles for four-position motion generation', American Society of Mechanical Engineers, Design Engineering Division (Publication) DE, pp. 253-262.
This paper describes a rectified synthesis method where a rigid body of a six-bar linkage with well-defined transmission angles is guided to pass through four precision positions. The procedure includes the elimination of circuit, branch, and order defects. This is achieved by decomposing the six-bar mechanism into groups of vector pairs called dyads and groups of three vectors called triads which are rectified using the algebraic method of synthesis. The procedure has been implemented for a Watt I crank-driven six-bar linkage in the interactive synthesis package RECSYN.
Chung, WY & Waldron, KJ 1993, 'Integrated control strategy for multifingered systems', American Society of Mechanical Engineers, Dynamic Systems and Control Division (Publication) DSC, pp. 263-270.
A method of force allocation by optimizing the friction angles at finger contacts was combined with the computed torque method to find the torques to be commanded at finger joints for multifingered systems. In this way, slip can be avoided when the object is grasped or manipulated. The proposed method can be efficiently used to find the input torques, and is applicable for real-time application. A history-based method is also proposed to improve the smoothness of the input torque commands. Three dimensional simulation results are given.
Chung, WY & Waldron, KJ 1993, 'Force distribution by optimizing friction angles for multifinger system', Proceedings - IEEE International Conference on Robotics and Automation, pp. 717-722.
An efficient way of finding the force distribution by optimizing the contact friction angles, which are the angles between the contact forces and contact normals, for multi-finger grasping systems was developed. Three steps, projection, residual wrench equilibrium, and optimization, are proposed to solve the force distribution problem. Examples are presented to show how the proposed method works. The results are also compared to those obtained by using Lagrange multipliers. Furthermore, the proposed method shows sufficient efficiency to be used for real-time control applications.
Song, SM, Lu, FH, Chen, NX & Waldron, KJ 1992, 'Determination of the shortest crank in four position synthesis: a numerical apporach', American Society of Mechanical Engineers, Design Engineering Division (Publication) DE, pp. 315-321.
The shortest crank of a four position synthesis can be determined by solving a statically determinate five-bar structure and a set of seven nonlinear equations have been proposed for this purpose. In this paper a numerical method which can directly solve the shortest crank is presented. It is found that a direct implementation of the original seven equations has two problems: many spurious solutions and poor numerical stability. And the spurious solutions are of the following two types: solutions with incorrect signs of angles and solutions with incorrect geometry. In order to solve the problems, a set of ten equations is developed and parameter perturbation method is applied. Furthermore, a set of eight equations is developed for better numerical stability. Both the ten and eight equations can eliminate the spurious solutions with incorrect geometry. Yet the spurious solutions with incorrect signs of angles can only be rectified after convergence. An automatic search algorithm is included to automatically search the shortest crank in the solution space. Many examples are given to illustrate this numerical approach.
Venkataraman, SC, Kinzel, GL & Waldron, KJ 1992, 'Optimal synthesis of four-bar linkages for four-position rigid-body guidance with selective tolerance specifications', American Society of Mechanical Engineers, Design Engineering Division (Publication) DE, pp. 651-659.
In practical rigid-body guidance problems, very often one or more of the design positions need not be generated exactly. Further, extreme accuracy at the design positions is somewhat pointless considering the inherent limitations in linkage manufacturing processes. This emphasizes the requirement of synthesis techniques to be able to handle tolerance specifications on the nominal design positions. A favorable offshoot of the tolerance incorporation would be the accompanying increase in the solution space of the synthesis problem thereby yielding better linkage solutions.
Agrawal, SK & Waldron, KJ 1988, 'Impulsive model for a quadruped running machine', American Society of Mechanical Engineers, Dynamic Systems and Control Division (Publication) DSC, pp. 139-148.
A model for a quadruped running machine is proposed in which controlled longitudinal and vertical impulses are delivered to the legs during support phase. A steady description of the machine is when the states at the beginning of successive cycles are invariant except for a prespecified traverse in the longitudinal direction. A graphical method is outlined to obtain steady solutions for quadruped gaits. Some representative examples of gaits are solved for the possible infinity of solutions in which a pair of feet hit the ground in unison such as the pace, bound and trot.
Lai, JY, Nair, SS, Singh, R & Waldron, KJ 1987, 'DYNAMIC SIMULATION AND CONTROL OF WALKING MACHINE LEG.', American Society of Mechanical Engineers, Dynamic Systems and Control Division (Publication) DSC, pp. 117-126.
Mobility and computer control of legs is one of the most important design considerations in mobile robotic systems. Their characteristics and limitations can be studied using a mathematical simulation model. In this study, a nonlinear dynamic model of a hydraulically controlled leg of a walking vehicle is developed. It includes the leg dynamics, the actuation system dynamics, modes of operation and control aspects. Comparison of experimental data with that from the simulation shows that the model predicts the system behaviour accurately. The model has been used to study and improve system response characteristics.
Klein, G, Waldron, K & Cooper, B 1986, 'Mars rover', AIAA/SOLE 2nd Aerospace Maintenance Conference, 1986.
© 1986, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved. The system integration issues associated with the design of Rovers for Mars grounfi surface operations are addressed in this paper. Requirements are established for both long distance traverse between geology sites and for geologic survey operations. To satisfy these mission requirements, a semi-autonomous vehicle design has been proposed and its performance capabilities are assessed. Furthermore, the mobility, power consumption, coordination and control (maneuverability), and reliability Issues associated with the design of mobility systems to permit vehicle traverse over rugged terrain are examined and the direction of future work required to address these issues Is outlined.
Waldron, KJ, Waldron, MB & Wang, M 1986, 'EXPERT SYSTEM FOR INITIAL BEARING SELECTION.', American Society of Mechanical Engineers (Paper).
A simple expert system for initial selection of bearings is described in this paper. This selection process represents a node in a design decision network, and is typical of a number of situations in which the designer must select from among diverse possibilities. The expert system is intended to be the front end of a program that includes algorithms for the sizing of bearings of selected type, and which accesses a data base of standard sizes with load life ratings for those types which are available in this form.
Song, SM & Waldron, KJ 1986, 'GEOMETRIC DESIGN OF A WALKING MACHINE FOR OPTIMAL MOBILITY.', American Society of Mechanical Engineers (Paper).
The design of the geometry of a walking machine depends to a considerable extent on the applications for which the machine is intended. Nevertheless, there are some very general principles and approaches which may be applied. This paper deals with the geometric design of a hexapodal walking machine which is to possess optimum mobility on varied terrain. This problem both illustrates, and serves as a vehicle for, the development of these general principles.
Tsai, MJ & Waldron, KJ 1986, 'GEOMETRIC CHARACTERISTICS OF INDUSTRIAL ROBOTS.', American Society of Mechanical Engineers (Paper).
An algorithm for generating the workspace for manipulator geometries involving orthogonal and parallel joint axes was developed. This algorithm can handle industrial robots with revolute joints as well as with prismatic joints. In addition, a technique based on the Gaussian Divergence Theorem has been introduced for computation of workspace volume, centroid, and moments of inertia about the three principal axes. This unique technique permits a closed form, high accuracy, quantitative measurement of geometric properties. These algorithms have been implemented in an interactive computer graphic program providing an efficient method for design and evaluation of the regional structure of an industrial robot.
Song, SM, Lee, JK & Waldron, KJ 1985, 'MOTION STUDY OF TWO AND THREE DIMENSIONAL PANTOGRAPH MECHANISMS.', Proceedings - OSU Applied Mechanisms Conference (Oklahoma State University).
Coupling of vertical, horizontal and rotory motions in manipulators slows down calculating speed for real time control and lowers system energy efficiency. Pantograph mechanisms are being used as manipulators to remove the coupling of motion. Methods which are used to determine the workspace of pantograph type manipulators are illustrated in an example. Some aspects of structural design are also discussed.
Waldron, KJ, Song, SM, Wang, SL & Vohnout, J 1985, 'MECHANICAL AND GEOMETRIC DESIGN OF THE ADAPTIVE SUSPENSION VEHICLE.', pp. 295-306.
Some aspects of the mechanical and geometric design of the adaptive suspension vehicle are presented. In particular, there is an emphasis on aspects of the leg design and vehicle geometry, which affect the ability of the vehicle to operate on steep grades or to cross obstacles. A mechanism that maintains the attitude of the foot approximately parallel to the body is described. Geometric aspects of maintaining static stability on steep grades are discussed. Geometric and gait sequence aspects of crossing severe obstacles are also discussed.
Pery, A, Gardner, JF & Waldron, KJ 1985, 'DESIGN AND TESTING OF A HIGH PERFORMANCE HYDRAULIC POWER SYSTEM FOR A LEGGED LOCOMOTION APPLICATION.', Proceedings of the American Control Conference, pp. 730-736.
The requirements imposed on the actuation system of an energy-autonomous, six-legged walking vehicle are unique and rigorous. The analysis, design, and testing of such an actuation system for the adaptive suspension vehicle (ASV) at Ohio State University is presented. Special attention is given to the synthesis of the general system configuration, which is a pump-controlled hydraulic system. The selection, design an testing of individual components and systems are discussed. The system developed and designed for the ASV has reasonably large bandwidth, compatible with equivalent familiar valve control systems. This system, although designed for a rather unique application, may eventually find its way into more conventional applications, such as in the heavy-duty robotics field.
Song, SM, Lu, FH & Waldron, KJ 1985, 'NUMERICAL METHOD IN DETERMINATION OF THE SHORTEST CRANK IN FOUR POSITION BURMESTER SYNTHESIS.', Proceedings - OSU Applied Mechanisms Conference (Oklahoma State University).
A numerical implementation based on the Newton-Raphson method of solving seven nonlinear equations is presented. A set of eight simultaneous and nonlinear equations is able to eliminate the spurious solutions which give incorrect geometry, and the spurious solutions which have wrong signs of angles are detected by the computer after convergence. The accurate length and position of the shortest crank can then be determined by a few trials.
Waldron, KJ 1985, 'MECHANICS OF MOBILE ROBOTS.', pp. 533-544.
The interaction of the mechanics of a mobile platform with control and sensing hardware and software is important to performance in robotic applications. In this paper the basic principles involved will be reviewed, and new material on comparative characterizations will be presented. The application of those principles to a specific example: the Adaptive Suspension Vehicle, will be presented.
Waldron, KJ, Brown, TF, Vohnout, V, Kinzel, G & Srinivasan, K 1985, 'TWO EXPERIMENTS ON LEGGED LOCOMOTION.', Proceedings - OSU Applied Mechanisms Conference (Oklahoma State University).
This paper contains a discussion of the OSU Monopod and the DUWE (Dynamic Unpowered Walking Experiment). These devices were constructed to experimentally verify ideas relating to legged locomotion with low specific resistance. These ideas were incorporated into the design of the Adaptive Suspension Vehicle. The DUWE was also used to explore the mechanics of ballistic leg return and the energetic interactions of the legs and body of a multi-legged machine.
Chuang, JC & Waldron, KJ 1982, 'SYNTHESIS WITH MIXED MOTION AND PATH GENERATION POSITION SPECIFICATIONS.', American Society of Mechanical Engineers (Paper).
Song, SM & Waldron, KJ 1981, 'THEORETICAL AND NUMERICAL IMPROVEMENTS TO AN INTERACTIVE LINKAGE DESIGN PROGRAM - RECSYN.', Proceedings - OSU Applied Mechanisms Conference (Oklahoma State University).
Waldron, KJ & McGhee, RB 1986, 'The Adaptive Suspension Vehicle'.
: This paper provides a description of the Adaptive Suspension Vehicle. The vehicle uses a legged, rather than a wheeled or tracked, locomotion principle, and is intended to demonstrate the feasibility of systems of this type for transportation in very rough terrain conditions. The vehicle is presently under test, with installation and validation of software modules for different operational conditions scheduled for completion by the end of 1986. © 1986 IEEE