Spring efficiency assessment and efficient use of spring methods of statically balanced planar serial manipulators with revolute joints only

Abstract. This paper proposes a spring efficiency assessment of statically spring-balanced planar serial manipulator. The admissible configurations for the static balancing manipulators without auxiliary links have been determined in past. Gravity is balanced by configuration systematically; however, also contains counter-effects between springs. Conceptually, with fewer springs, there less burden on system, which means that springs are used more efficiently, and accordingly, system would be safer, its service life longer. In this study, energy represented quadratic form. coefficients form represent change elastic relative position links, named “elastic pseudo-stiffness”. Compared to gravity energy, those pseudo-stiffnesses regarded as positive contributions spring, while contain seen negative ones. Spring defined ratio pseudo-stiffnesses, has total pseudo-stiffnesses. To use counter-effects, functions parameters, need decreased, including stiffness attachment location links. A method efficiently adjusting parameters developed. Furthermore, it found that, attached adjacent 100 %, decreases number joints over spans increases. manipulator negatively correlated payload. As an example, 3 degrees freedom (DOF) shown at end.