workspace analysis is one of the most important issues in the robotic parallel manipulator design. ‎however, ‎the unidirectional constraint imposed by cables causes this analysis more challenging in the cabledriven redundant parallel manipulators. controllable workspace is one of the general workspace in the cabledriven redundant parallel manipulators due to the dependency on geometry parameter...

We study Jacobian inverse kinematics algorithms for mobile manipulators composed of a nonholonomic mobile platform and a holonomic onboard manipulator. In general, the Jacobian algorithms converge locally, often producing weird end effector and platform trajectories. In the paper we use the existing theory of Newton algorithms in order to improve the quality of convergence of the Jacobian algor...

This paper presents a motion planning method for mobile manipulators for which the base locomotion is less precise than the manipulator control. In such a case, it is advisable to move the base to discrete poses from which the manipulator can be deployed to cover a prescribed trajectory. The proposed method finds base poses that not only cover the trajectory but also meet constraints on a measu...

This article presents a multi-agent approach for controlling autonomous mobile manipulators. The proposed approach assigns a hybrid agent (Mobile base agent) for the control of the mobile base, a reactive agent (Joint agent) to each degree-of-freedom (dof) of the manipulator, and a Supervisory agent to assure coordination and to synchronize the work of the whole agents of the system. The initia...

In this paper, force/motion tracking control is investigated for nonholonomic mobile manipulators with unknown parameters and disturbances under uncertain holonomic constraints. The nonholonomic mobile manipulator is transformed into a reduced chained form, and then, robust adaptive force/motion control with hybrid variable signals is proposed to compensate for parametric uncertainties and supp...

Deep reinforcement learning produces robust locomotion policies for legged robots over challenging terrains. To date, few studies have leveraged model-based methods to combine these skills with the precise control of manipulators. Here, we incorporate external dynamics plans into learning-based mobile manipulation. We train base policy by applying a random wrench sequence on robot in simulation...

In this paper, finding the maximum load carrying capacity of mobile manipulators for a given two-end-point task is formulated as an optimal control problem. The solution methods of this problem are broadly classified as indirect and direct. This work is based on the indirect solution which solves the optimization problem explicitly. In fixedbase manipulators, the maximum allowable load is limit...

This paper proposes an architecture to achieve cooperative behaviour among a set of robotic devices. The architecture, with a pure reactive nature privileges the use of local decision mechanisms instead of centralized ones. The performance assessment for the execution of a class of tasks common in the operation of mobile manipulators is made via a particular mission composed by a number of tasks.