Manipulator motion control in operational space using joint velocity inner loops

Neural-network-based two-loop control of robotic manipulators including actuator dynamics in task space

“…According to [9], the following kinematic control law is designed to generate the desired joint velocity…”

“…The computational burden would degrade the performance of the system. Kelly et al [9] addressed a motion control scheme of robotic manipulators endowed with joint velocity feedback inner loop in operational space, which was a motivation of this paper for the two-loop control structure. However, the proposed two-loop control structure required exact knowledge of the dynamics of robotic manipulators.…”

Velocity field control of robot manipulators by using only position measurements

“…This paper introduces a velocity field controller based on the hierarchical structure of [9] and [10], i.e., a two loops of feedback controller. By using the ideas in [11][12][13], the proposed solution follows the concept of replacing the joint velocities by the filtering of the joint positions and the desired velocity field via a stable first order filter.…”

Operational space trajectory tracking control of robot manipulators endowed with a primary controller of synthetic joint velocity

“…The most common secondary loop is designed with the aim of satisfying either the motion or the force control objective. The papers [11][12][13][14][15][16][17][18][19], show designs of robot controllers based on a primary joint velocity and secondary task-based loops.…”

“…We found that industrial robots are provided with a primary (inner) joint velocity loop and a secondary (outer) task-based loop [9][10][11]. The most common secondary loop is designed with the aim of satisfying either the motion or the force control objective.…”