The Role of Robot Payload in the Safety Map Framework In practical robotic applications various types of tools are attached for manipulating objects. Besides adding gravitational load to the robot, which results in larger joint torques, such payloads influence the collision safety characteristics through changing surface curvature properties, reflected mass and effective robot speed along a desired motion direction. In this paper, we evaluate the effect a known, unactuated payload that is attached to the endeffector has on the intantaneous reflected inertial parameters and maximum task velocity of a robot. The proposed mass update approach relies on the analysis of the kinetic energy matrices, while the velocity maximization is tackled by formulating static optimization problems with different constraints on angular motion of the endeffector. Finally, for analyzing the validity of the introduced approach in the framework of Safety Maps, we discuss simulation results of a PUMA 560 robot that has an exemplary payload attached to its endeffector.

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.