This work presents a fault-tolerant robotized system based on joint blockage, which permits preventing forced stops in production processes when accidents or faults limit the normal mobility of industrial robot links. The system is composed of an intelligent algorithm and a redundant SCARA (Selective Compliant Assembly Robot Arm) manipulator robot with more joints and links than the minimum quantity necessary for conducting assigned tasks. This characteristic allows robots to reconfigure themselves online, even after their joints suffer mechanical or electrical failures that cannot be prevented through maintenance. Modeling, control, and implementation of a real redundant robot with 5 Degrees Of Freedom (DOF) of the SCARA manipulator type are presented. A simulation environment including the actuator dynamics is elaborated. A 5 DOF manipulator robot, a communication interface and a signal conditioning circuit are designed and implemented for feedback. Three control laws are executed in: a simulation structure (together with the dynamic model of the SCARA type redundant manipulator and the actuator dynamics) and a real redundant manipulator of the SCARA type carried out using MatLab/Simulink programming tools. The results, obtained through simulation and implementation, are represented by comparative curves and RMS indices of the joint errors, and they show that the redundant manipulator, both in the simulation and the implementation, followed the test trajectory with less pronounced maximum errors when using the adaptive controller than the other controllers, with more homogeneous motions of the manipulator robot. This type of fault-tolerant robotized system could be used in a large number of mining processes and metal operations. However, to date, this type of physical redundancy-together with intelligent control algorithms-has not been included in commercial SCARA robots.
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