Energy intensity analysis and costs of Fanuc AM100iB robot work

This paper examines issues of energy intensity and the cost of operation of the industrial Fanuc AM100iB robot. The investigated robot represents a type of transportation and manipulation machine, with six degrees of freedom and cylindrical workspace in which all kinematic couples are rotational. In such machines, the cyclograms of drive work are strongly differentiated, and result from their build and means of control. Nowadays, the methods used for energy intensity analysis and the cost of such machines' operation are based on rough estimates, carried out using long-term measurements. The proposed approach allows for the realization of such analyse s very precisely. This opens new possibilities for making strategic decisions in a production plant, concerning the production process. The energy intensity analysis, proposed in the paper, is based on the results of computer simulations of the investigated robot's work. The simulations have been made using a numerical model of the industrial robot. The prepared model is equipped with a system for generating a reference trajectory, a linear interpolator, a system for calculating inverse kinematics, a system for speed profile generation of a robot's TCP point, setpoint-tracking controllers with a cascade structure and feed forward loops and static models of viscous friction. The systems are responsible for control of the numerical model, which defines the type of kinematic couples, the length of the arms, values of their masses, positions of their centers of gravity and their tensors of mass moment of inertia and ratios of mechanical transmissions. The numerical model was supplemented by analytical calculations. Thanks to this, from the total loads acting on the motor shafts, the gravitational, inertial, centrifugal and Coriolis torques were extracted. This allowed the detailed analysis of their influence on the total energy consumption. Based on the results of the performed simulations, the mechanical power on the motor shafts and the amount of heat emitted from the robot drive systems were calculated. By summing the values of calculated power through the whole period of analysis, the total actual electric energy consumption was obtained. Finally, costs incurred for the payment of charges for the consumed energy were calculated.