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A fully compliant constant-force mechanism that uses an initially angled parallelguiding mechanism is proposed. A pseudo-rigid-body model (PRBM) of the mechanism is developed and validated using both finite element models and experimental prototype testing. The PRBM is used as a preliminary design tool to identify parameters that result in a constant-force mechanism. An adjustable version of the mechanism is also proposed and is used to assess the range of validity of the PRBM and highlights how the system response can be varied by changing the flexible beams inclination. A finite element based optimization is used to create a modified version of the mechanism that incorporates beam-end rotation effects and offers greater performance. Potential applications for the mechanism are discussed and it is demonstrated as a component of a statically balanced system. 10 for constant-force mechanisms range from devices such as snap fits [12], to microelectromechanical systems [13, 14]. Early constant-force mechanisms were constant-force tension springs which are also known as Negator springs [15]. These springs consist of a strip of spring steel in a tightly wound coil and are found in consumer items such as tape 15 measures and pull-starts. Nathan proposed a rigid link constant-force generator

Abstract. This paper describes the conception, modeling, and development of a fully compliant two-degreeof-freedom pointing mechanism for application in spacecraft thruster, antenna, or solar array systems. The design objectives and the advantages of a compliant solution are briefly discussed. Detailed design decisions to meet project objectives are described. Analytical and numerical models are developed and subsequently verified by prototype testing and measurements in several iterations. A final design of the 3-D printed titanium monolithic pointing mechanism is described in detail and its performance is measured.

This work presents a general method of statically balancing flexural hinges. Using a set of nondimensional parameters, we show that one can quickly design a statically balanced rotational flexure. First, a balancing method is developed for an idealized hinge/torsion spring system. This method is then extended to load-dependent systems and is demonstrated with the design of a balanced cross-axis-flexural pivot with stiffness that varies as a function of compressive preload. A physical prototype is built and tested to verify the design method. This method is general for any system that has a well understood stiffness response to an applied compressive load.

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