Steel compliant Cardan universal joint

In this paper, a compliant Cardan universal joint made of steel is introduced. This is the first steel compliant universal joint that is reported in the literature. The mechanism is produced from two different sheet metals; thus, it has the advantage of easiness in manufacturing. Many mechanisms with different dimensions are designed. Resultant stresses at flexural hinges are determined via analytical and finite element analysis method. Torque transmission capacities of these mechanisms are determined. Guidelines, trends, and parameter trade-offs for the design of such mechanisms are presented. Fatigue life of these mechanisms is estimated theoretically. Further, one of these mechanisms is manufactured and tested for fatigue strength. It is verified that results of experiments are consistent with theoretical predictions. It is strongly believed that the steel version of compliant Cardan joint has a great potential to be used in industry.