Nonlinear response and fluctuating torque characteristics of the pneumatic muscle actuators at crankshaft application

The present study aims to investigate the availability of pneumatic muscle actuators ( PMAs) for producing continuous rotational motion by simulating a crankshaft drive system actuated by artificial muscles. It examines the nonlinear behavior and fluctuating torque characteristic of the PMAs in the crankshaft drive system over the experimentally determined tensile forces. It also looks at the effects of the joint structure, the contraction rate, the timing of the pressurization, the use of a mechanical stopper, and the number of PMAs. It identifies and examines five design versions, including the variations of these parameters. It investigates the range of these parameters for an ideal configuration of the PMA-based crankshaft drive system. The results showed that 44.9 N·m average crankshaft torque fluctuating between 18 and 81.4 N·m is achievable using DMSP-20-300 PMAs at 600 kPa air pressure. Regarding continuous rotational motion, the crankshaft application differs from the PMA-based studies in the literature. The proposed approach fills a gap in the spectrum of activation technologies since it converts linear stroke into continuous and fluctuated rotational output through intermittent oscillating pulling motion generated by a single pneumatic artificial muscle.