| The teleoperation involves all the methodologies and technologies enabling a human operator to perform a dangerous or human inaccessible task from a distance through the use of an intermediate mechatronic (robotic) system. However, Single-Master Single-Slave (SMSS) teleoperation can not be performed in some applications, e.g. so heavy or large object transportation and large area searching that "one" slave robot can not handle and etc. Therefore, based on preliminary research of the SMSS teleoperation, this report proposes adaptive control for Single-Master Multi-Slave (SMMS) teleoperators involving formation control, sensor based switching function to enhance transparency if no human induced error is detected, and a contact force compensator to achieve contact stability. Crucial issues about human induced errors in the teleoperation control are raised, and an approach to accomplish a desired task without being affected by the human induced errors is studied. It is promising that the addition of local robot intelligence keeps the system away from being affected by not only communication delays but also human induced errors.;There are several aspects of enhancing the conditional transparency and stabilizing oscillating contacts when a slave robot or a group of slave robots performs tasks consisting of different motions, e.g. constrained, unconstrained, and transition between the two motions. First, for the constrained motion of the slave robots, the adaptive impedance control method with a force compensator whose adaptation law includes master and slave errors and estimate of slave environment is developed. The purpose is to adapt master and slave impedances to improve the transparency, if no human induced error is detected. Otherwise, the transparency is compromised. At the same time, if the contact is made, the contact force is accommodated by using the force compensator. Second, the sensor based switching function is made based on human induced error detection. As human induced errors exist, the function automatically allows the robotic intelligence to dominate over the manual commands. Third, in SMMS, the adaptive formation control scheme with obstacle avoidance and/or target transportation is proposed. The efficacy of the method was validated by haptic simulations and evaluated by experiments in terms of the transparency and the stability subjected to transmission delays. |
