Design and optimization of a general planar zero free length spring

A zero free length (ZFL) spring is a spring with special properties, which is commonly used in static balancing. Existing methods to create ZFL springs all have their specific drawbacks, which rises to the need of a new method to create such a spring. A method is proposed to design planar ZFL springs with specified stiffness (250–750 N/m)...

Parameter analysis for the design of statically balanced serial linkages using a stiffness matrix approach with Cartesian coordinates

A statically balanced system is in equilibrium in every pose. In classical balancing solutions for serial linkages, each DOF is balanced by an independent element. Disadvantages are increased mass and inertia for counter-mass, and auxiliary links for spring solutions. Recent literature presents a method for balancing serial linkages without...