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A large-scale combined legged and wheeled vehicle with anthropomorphic legs is presented. This concept combines the advantages of a walking machine with the stability of a wheeled vehicle. The leg utilises a spherical hip joint, a revolute knee joint and a passively pivoting foot. Due to the size of the system linear hydraulic actuators are used, and thus kinematic loops are created in the mech...

Identification of robot kinematic errors during the calibration process often requires accurate full pose measurements (position and orientation) of robot end-effectors in Cartesian space. This paper proposes a new method of full pose measurement of robot end-effectors for calibration. This method is based on an analysis of the features of a set of target points (placed on a rotating end-effect...

Planar motion can be synthesized with two-degree-of-freedom curvature theory by using the second-order Taylor series to coordinate planar path-tracking systems. Second-order control-variable coordination generates tracking error away from the reference point, and tracking becomes erratic when the driving variable experiences a dwell in its trajectory. This paper extends the technique through an...

Motion planning for coupled rigid bodies in a horizontal plane is investigated. The rigid bodies are serially connected by passive revolute joints. The dynamic constraints on the system are second-order nonholonomic constraints. We attempted to control those n coupled rigid bodies by the translational acceleration inputs at the first joint. If each rigid body is hinged at the center of percussi...

This paper exposes the experimental evaluation of a new technique for the estimation of the instantaneous helical axis of movement of human anatomical joints. The measurement technique, using a six degrees of freedom spatial electro-goniometer, is tested onto a simple revolute joint and onto a subject’s knee. A motion capture system with active optical markers is used at the same time in order ...

Robust nonlinear control of flexible-joint robots requires that the link position, velocity, acceleration, and jerk be available. In this paper, we derive the dynamic model of a nonlinear flexible-joint robot based on the governing Euler-Lagrange equations and propose extended and unscented Kalman filters to estimate the link acceleration and jerk from position and velocity measurements. Both o...

This paper examines the role of grasper compliance and kinematic configuration in unstructured environments, where object size and location may not be well known. A grasper consisting of two two-link planar fingers with compliant revolute joints was simulated as it passively deflects during contact with a target object. The kinematic configuration and joint stiffness values of the grasper were ...

We address the synthesis of serial chain spatial mechanisms with revolute joints in which the rotations about the joints are coupled via cables and pulleys. Such coupled serial chain mechanisms o er a middle ground between the more versatile and compact serial chains and the simpler closed chains by combining some of the advantages of both types of systems. In particular, we focus on the synthe...