• cost function
• effort
• haptics
• inverse kinematics
• redundancy
• RULA
• shared control

Shared control is a suitable technology for various robotic applications in which a robotic system and a human operator are working to reach a common goal. The purpose is to combine the efficiency of automatic control with human judgment and experience. This type of control is well assorted with a remote system in a medical or nuclear environment. Working in a human environment it is important to focus also on the effort perceived by the user, especially if it is the case of repetitive tasks. The heart of this thesis is centered on the perception of the human and on how to make as comfortable as possible the tasks to perform. A literature review has been prepared on the method of calculating the effort and risks factors in the workplace. The chosen method is the RULA, Rapid Upper Limb Assessment, which evaluates the exposure of individual workers to ergonomic risk factors associated with upper extremity. In this scenario the user interfaces with a haptic manipulator, Virtuose 6D, in teleoperation with a robotic arm, Franka Emika, performing pick and placing tasks. To facilitate the execution of the tasks, the operator is helped by the haptic manipulator to reach the positions to grasp and release the objects. At the same time, the user receives a force feedback regarding the minimization of the effort following the RULA factor. One way to provide this type of guidance is by having a cost function to minimize and applying forces that guide the user towards the minimum of this function. A user study of 10 candidates has tested the reliability and effectiveness of the approach.