This paper presents a novel bilateral control scheme for pneumatic teleoperation systems that are actuated by low cost solenoid valves. A sliding mode control is incorporated into a two-channel, bilateral teleoperation architecture involving position-position, force-force, or force-position schemes. An analysis of stability and transparency of the closed-loop teleoperation system is carried out. The proposed control design is verified on a single-degree-of-freedom pneumatic teleoperation system with four on/off solenoid valves. Moreover, simulation results demonstrate high accuracies in terms of position and force tracking in the teleoperation system.

This paper proposes a sliding mode law for precise position control with minimal switching activity for a robotic system that uses on/off (solenoid) pneumatic actuators, For a two-chamber pneumatic actuator with four binary solenoid valves, there is a total of sixteen possible input combinations defined directly from the state of the four on/off solenoid valves present in the system. However, only seven of these discrete operating modes are considered both functional and unique. Accordingly, we use a seven-mode sliding controller that minimizes the position error using modes that have both the necessary and sufficient amounts of drive energy and, thus, involve reduced switching activity. An analysis of the closed-loop system stability is carried out. The performance of the proposed control design is experimentally verified on a single pneumatic actuator comprising of two chambers driven by four on/off solenoid valves.

This paper presents an enhanced sliding mode control for pneumatic master-slave teleoperation systems that are actuated by low-cost solenoid valves. A five-mode sliding control is incorporated into position-position, force-force, and force-position teleoperation architectures. While on/off valve pneumatic actuators have previously been modeled as having three discrete operating modes, an extension to five discrete control levels as proposed here helps to improve the actuator dynamic performance and reduce the switching activities of the valves. Stability and transparency analyses of the closed-loop teleoperation system are carried out. The proposed control design is experimentally tested on a single-degree-of-freedom pneumatic teleoperation system. Experimental results demonstrate high accuracies in terms of position and force tracking in the teleoperation system.

This paper presents a new predictive hybrid control law for a pneumatic teleoperation system using solenoid valves. Based on a predictive model of the mass flow rate of the valves, this method is used within a four-channel (4CH) bilateral control architecture for haptic teleoperation. An analysis of the controller parameters is carried out in order to achieve acceptable performances. The results show that a good accuracy in position and force tracking of the teleoperation system is obtained.

This paper presents a new predictive hybrid control law for a pneumatic teleoperation system using solenoid valves. Based on a predictive model of the mass flow rate of the valves, this method is used within a four-channel (4CH) bilateral control architecture for haptic teleoperation. An analysis of the controller parameters is carried out in order to achieve acceptable performances. To evaluate the new strategy, a comparison study has been performed with a classical PWM control of a teleoperation system. The results show that the accuracy in position and force tracking in steady state but also the dynamic behavior of the pressures are better in the case of hybrid control than PWM control.