# Wedge Design and Dynamic Characteristics Analysis of Unequal-Length Wedge Slant Support Clutch
## 1 Introduction  
The slant support-type overrunning clutch has a large bearing capacity and stable power transmission and can adapt to different working conditions [1]. NASA began studying high-speed aviation slant support clutches in the 1970s. [PERSON] et al. [2] used the high-speed clutch in the helicopter as the research object, proposed a preliminary dimension design method and stress analysis at 20,000 rpm, and applied it in the design of the UH-60A Black Hawk helicopter. [PERSON] et al. [3] used a combination of finite element analysis and experimental tests to study the influence of wedge contour changes on contact performance and transmitted torque but did not study the disengagement process. [PERSON] et al. [4] established a damping model with variable preload displacement and constant amplitude attenuation ratio, based on which an analytical model of the overrunning clutch was constructed, ignoring the influence of wedge contour changes. [PERSON] et al. [5] established a new multi-circular-arc wedge-block oblique-breaced clutch and proposed an improved geometric variable coordination method to improve the model accuracy, but no experimental verification was carried out. [PERSON] et al. [6; 7] established a piecewise-wedged dynamic model for a diagonal clutch-quasi rigid rotor system (SC-QRRS, SPRAG clutch-quasi rigid rotor system), based on which combined dynamic models of an SC-QRRS with multi-arc and logarithmic spirals were established. [PERSON] et al. [8; 9], aiming at the problem of the wear of the wedge and the inner and outer rings due to the contact cyclic force, established the wear formula by an analytical method and proposed the failure criterion method of the wear limit value but did not carry out the optimization study of the dynamic engagement. [PERSON] et al. [10], considering factors such as the meshing stiffness of the time-varying gears, static transmission error, and nonlinear backlash, established the transmission system model of a double-shaft assembly of an inclined brace clutch; the dynamic response of the inclined-brace clutch under different operating conditions was studied. [PERSON] et al. [11] established a four-degree-of-freedom nonlinear transverseand torsional vibration model of a two-shaft system with a diagonally braced clutch and provided a solution for the dynamic design and vibration control of the system, but the dynamic characteristics of clutch dynamic engagement and disengagement were not studied. [PERSON] [12] established a model of the center of gravity of a wedge block and studied its influence on the contact force, engagement, and release performance of an inclined-brace clutch. [PERSON] et al. [13] studied the wear performance of a clutch support spring in an overrunning state, which provided a reference for the design and optimization of support springs. [PERSON] [14] established an analytical model of the internal interaction of multi-circular-arc surfaces in the process of engagement and further proposed the analytical modeling and optimization of a logarithmic-surface clutch with profile modification; the possibility of extrusion failure and low-cycle fatigue of the upper and lower cams was reduced. [PERSON] et al. [15] analyzed the law of spring fatigue fracture caused by abnormal wear and extrusion of an inclined stay clutch from the perspective of macro and micromorphology. [PERSON] et al. [16] improved the clutch engagement failure problem by adjusting the spring parameters, ignoring the influence of wedge design on the engagement process. [PERSON] et al. [17] proposed a new double-arc spray overrunning clutch, which overcomes the disadvantages of poor transmission capacity and low torsional rigidity of transmission devices but lacks quantitative analysis between contact stress and fatigue life. [PERSON] et al. [18] evaluated the differential engagement time and impact load of a high-speed oblique-braced clutch, which can provide a reference for the impact load estimation of similar clutches.