Physical HumanRobot Interaction under Joint and Cartesian Constraints This paper handles the problem of including Cartesian and joint constraints in the stack of tasks for torquecontrolled robots. A novel approach is proposed to handle Cartesian constraints and joint constraints on three different levels: position, velocity and acceleration. These constraints are included in the stack of tasks ensuring the maximum possible fulfillment of the tasks despite of the constraints. The algorithm proceeds by creating two tasks with the highest priority in a stack of tasks scheme. The highest priority task saturates the acceleration of the joints that would exceed their motion limits. The second highest priority task saturates the acceleration of the Cartesian directions that would exceed their motion limits. Experiments to test the performance of the algorithm are performed on the KUKA LBR iiwa.

ForceandMotion Constrained Planning for Tool Use The use of hand tools presents a challenge for robot manipulation in part because it calls for motions requiring continuous force application over a whole trajectory, usually involving large jointangle excursions. The feasible application of a tool, such as pulling a nail with a hammer claw, requires careful coordination of the choice of grasp and joint trajectories to ensure kinematic and force limits are not exceeded  in the grasp as well as the robot mechanism. In this paper, we formulate this type of problem as choosing the values of decision variables in the presence of various constraints. We evaluate the impact of the various constraints in some representative instances of tool use. To aid others in further investigating this class of problems, we have released materials such as printable tool models and experimental data. We hope that these can serve as the basis of a benchmark problem for investigating tasks that involve many kinematic, actuation, friction, and environment constraints.