Balancing of slider-crank and Scotch-yoke mechanisms by the use of mechanical resonance: Simulation and experiment

Unbalanced inertia forces, moments, and torques in slider-crank and Scotch-yoke mechanisms adversely affect performance, leading to vibrations, stress, and accelerated wear. This paper presents the application of mechanical resonance as a solution to mitigate these drawbacks. The modeling and investigations involve multibody simulations incorporating both rigid and flexible bodies, alongside experimental tests in various scenarios. The synthesis section covers the explanation of techniques for generating resonance, achieving optimal reciprocating body positioning, and gravity compensation. The analysis and comparison section examines and contrasts the input torque, reaction forces on the joints, shaking forces, shaking moments, and stresses in the bodies between the conventional and resonance setups. The findings indicate significantly improved dynamics under resonance conditions for both mechanisms. In the absence of non-conservative forces, the slider-crank mechanism experiences a reduction of up to 79.99 % for peak joint reaction force, 76.74 % for the RMS value, 81.6 % for peak inertia torque, and 82.2 % for RMS torque. Resonance in the Scotch-yoke mechanism entirely reduces torque fluctuation due to the harmonic nature of slider motion, thus practically eliminating reaction forces at main kinematic pairs.