Robust motion control of a robot manipulator via Integral Suboptimal Second Order Sliding Modes

Abstract

Abstract-This paper deals with the formulation of an Integral Suboptimal Second Order Sliding Mode control algorithm oriented to solve motion control problems for robot manipulators, taking into account the presence of unavoidable modelling uncertainties and external disturbances affecting the systems. The proposed algorithm is designed so that the socalled reaching phase, normally present in the evolution of a system controlled via a Sliding Mode controller, is reduced to a minimum. Moreover, since the relative degree of the relevant system output is suitably augmented through the use of an integrator, the control action affecting the robotic system is continuous, with a significant benefit, in terms of chattering alleviation, for the overall controlled electromechanical system. The verification and validation of our proposal have been performed by simulating the motion control scheme relying on a model of the considered robot, i.e. a COMAU SMART3-S2 anthropomorphic industrial robot manipulator, identified on the basis of real data.

Design of an Integral Suboptimal Second-Order Sliding Mode Controller for the Robust Motion Control of Robot Manipulators

“…To acquire the joints positions, resolvers are fastened on the three motors. The controller has a sampling time equal to t s =0.001 s. Note that, the performance obtained during experiments are comparable with the results attained in simulation, as published in [30]. Hereafter, for the sake of brevity, only the parametric and initial values of the algorithm applied in simulation are reported.…”

“…The comparison based on experimental tests with the results obtained by using a standard PD controller and the original Suboptimal algorithm shows the superiority of the present proposal and confirms its applicability in an industrial context. Note that a preliminary version of this work, not reporting the proofs of the results, and only including simulations has been published in [30].…”

A Sliding-Mode Virtual Sensor for Wheel Forces Estimation With Accuracy Enhancement via EKF

“…One key advantage of this evolution is the fixed number of calibration parameters. In fact, with the STBA method [34], there is no a-priori knowledge of the optimal number of regions in which the (σ,σ) phase-plane should be divided to get an efficient chattering alleviation. Conversely, with the EKF, the number of parameters to be calibrated depends on the dimension of the observed state.…”

“…By considering the derivative∆T of the output of the PI controller, given by (34), one can see that its value is bounded, as long as the input error e Fx is bounded and has bounded derivative. This can be proved straightforward, considering that the rate of change of the estimated forces is indeed determined by the chosen gain K x .…”

Research on Rotational Angle Measurement for the Smart Wheel Force Sensor

“…For example, F x is helpful to design an antilock brake system [6][7][8], and F z could be used in load spectrum analysis [9,10]. Now that in-wheel motors are finding increasingly utilization in new intelligent vehicles, the need for high precision measurement and control of the wheel forces is becoming more important than ever [11][12][13].…”