Guarantee Position Tracking Research Articles

A Boom Energy Regeneration System of Hybrid Hydraulic Excavator Using Energy Conversion Components

In this paper, a novel design of an energy regeneration system was proposed for recovering as well as reusing potential energy in a boom cylinder. The proposed system included a hydraulic pump/motor and an electrical motor/generator. When the boom moved down, the energy regeneration components converted the hydraulic energy to electrical energy and stored in a battery. Then, the regenerated energy was reused at subsequent cycles. In addition, an energy management strategy has been designed based on discrete time-optimal control to guarantee position tracking performance and ensure component safety during the operation. To verify the effectiveness of the proposed system, a co-simulation (using MATLAB and AMESim) was carried out. Through the simulation results, the maximum energy regeneration efficiency could achieve up to 44%. Besides, the velocity and position of the boom cylinder achieved good performance with the proposed control strategy.

Robustly stable switching neural control of robotic manipulators using average dwell-time approach

This paper addresses the robust switching tracking neural control problem for a robotic manipulator in the presence of uncertainties and disturbances. The proposed controller, which is a combination of a robust adaptive control technique, radial basis function neural network approximation and average dwell-time technique, can guarantee position tracking performance of robotic manipulator system, in the sense that all variables of the resulting closed-loop system are bounded and the H∞ disturbance attenuation level is well obtained. Simulation results on a two-link robotic manipulator show the satisfactory tracking performance of the proposed control scheme even in the presence of large modelling uncertainties and external disturbances by comparing it with PD control strategy.

Synchronization of bilateral teleoperators with time delay

Bilateral teleoperators, designed within the passivity framework using concepts of scattering and two-port network theory, provide robust stability against constant delay in the network and velocity tracking, but cannot guarantee position tracking in general. In this paper we fundamentally extend the passivity-based architecture to guarantee state synchronization of master/slave robots in free motion independent of the constant delay and without using the scattering transformation. We propose a novel adaptive coordination architecture which uses state feedback to define a new passive output for the master and slave robots containing both position and velocity information. A passive coordination control is then developed which uses the new outputs to state synchronize the master and slave robots in free motion. The proposed algorithm also guarantees ultimate boundedness of the master/slave trajectories on contact with a passive environment. Experimental results are also presented to verify the efficacy of the proposed algorithms.