29 01 20sol

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Industrial Automation, Communication and Data Management Prof. Cesana, Rocco, Tanca January 29, 2020 SOLUTION Industrial Automation, Communication and Data Management Prof. Matteo Cesana, Paolo Rocco and Letizia Tanca Consider a robot in interaction with a human as in the picture: 1. Explain what collaborative robotics is and why it is considered important for the small and medium enterprises. In collaborative robotics, humans and robots are cooperating at the same task without protective fences or other kind of barriers (laser scanners, optical barriers, etc.). It is a mode of interest for SMEs because of the easier installation of the robot (reduced footprint, no need for complicated infrastructure for safety purposes), the decrease of the deployment time, and the easier interfaces. 2. List the collaborative modes allowed by the safety standards. The safety standards (ISO 10218) lists four collaborative modes: • Safety-rated monitored stop • Hand guiding • Speed and separation monitoring • Power and force limitation 3. Consider now the robot in contact with the environment (for example the human). In a simplified analysis, we can represent the situation with a mass-spring-damper system as in the picture: /G4D /G46 /G70 /G4B /G44 Write the equations of the dynamic system that corresponds to the mass-spring-damper system. The dynamic model of the mechanical system can be written as: M ¨p + D ˙p + Kp = F If we choose as state variables x1 = p (position) and x2 = v (speed), as input variable u = F (force) and as an output variable y = p, position, the corresponding dynamic system is: ˙x1 = x2 ˙x2 = − K M x1 − D M x2 + 1 M u y = x1 4. Derive the expression of the transfer function of the mass-spring-damper system. Explain under what conditions on the parameters the system…