Increasing stability in model-mediated teleoperation approach by reducing model jump effect

Abstract

Model-mediated teleoperation is a predictive control approach to controlling haptic teleoperation systems whereby the environment force is virtually located on master side in order to increase the stability and transparency of the system. This promising approach, however, resulted in new challenges. One pivotal challenge is the model jump effect, which stems from the delay in correct creation of the virtual environment. Previous works endeavored to reduce this effect; however, they either led to transparency decrease or assumed simplified environment models. This paper proposed a control approach for this aim based on the idea of decoupling. This means that when a new environment has been identified, the operation is interrupted and no signal is transmitted between master and slave sides. During this time, both sides are controlled by their own sliding mode controllers until the system reaches stability. The main advantage of this method is its independence of environment type, which makes it usable for difierent kinds of applications. To verify the effectiveness of the proposed approach, simulation tests are conducted. The results show that the system is stable in interaction with hard and soft environments in the presence of large time delays in communication channels.