Study and implementation of non-parametric, kinematic compensation models for industrial manipulators

One of the most consistent problem in robotics nowadays is guarantee excellent performances for any kind of manipulator, in the most possible heterogeneous conditions. The aim of this thesis is to find a versatile method to compensate the position of a manipulator in order to guarantee a pose error lower than 0.5 mm. This research work, carried out in collaboration with Comau S.p.A., shows that by using a double step compensation, based on a non-parametric and kinematic model, it is possible to untie the compensation of the positioning error of a physical manipulator from its specific model (both dynamic and kinematic). The experiments have been conducted on a NJ 200 manipulator. Starting from real data, a first compensation model has been created by using B-Spline and a Modified Akima's algorithm and tested on a real machine with fixed orientation achieving satisfying results. Starting from the results of a compensation method developed by Comau in the case of non-fixed orientation, a further compensation has been designed in this thesis, leading to the creation of a hybrid compensation approach that guarantees (at least in simulation) optimal results, even if still based on some approximations.