Method for commanding an automated work cell

Method for controlling an automated work cell, wherein the work cell comprises:

• a robot arm articulated with at least three degrees of freedom, wherein the robot arm may be controlled according to articular instructions and comprising motors that are adapted to maneuver parts of the robot arm;
• a control center able to control the operation of the work cell by movement commands;
• a robot controller, including motor controllers each controlling the operation of a motor;
• a communication bus between the control center and the robot controller;
• wherein this control method comprises the steps of:
• y) calculating, by the control center, nominal articular instructions using a trajectory generator, based on the movement commands;
• z) transmitting the calculated nominal articular instructions, via the communication bus, to a calculation unit belonging to the robot controller;
• wherein this control method further comprises steps consisting of:
• a) calculating, by the calculation unit, Cartesian instructions corresponding to the nominal articular instructions;
• b) calculating, by the calculation unit, actual articular instructions from the Cartesian instructions, taking into account actual geometric parameters of the robot arm;
• c) calculating, for each nominal articular instruction and from the actual articulation instruction, an articular instruction correction value;
• d) calculation for each nominal articular instruction and from the established articular correction instruction, an effective articular instruction, wherein the effective articular instruction is the sum of the nominal articular instruction and the articular correction instruction;
• e) calculating control commands for each motor controller from the calculated effective articulated commands;
• f) transmitting the motor control instructions to each motor controller to control the corresponding motor according to the motor control instruction.