Robust optimal design of strain-gauge-based force sensors using moving morphable components method: enhanced sensitivity and reduced cross-interference

Designing force sensors with superior performance is always a challenging topic in the industry as well as in academia. This paper employs the moving morphable components method in order to design strain-gauge-based force sensors with high sensitivity and low cross-interference. The function of the Wheatstone bridge (half-bridge) is taken into account in the automatic design implementation to make it practically more feasible. Compared with our previous study on sensor design with only the high-sensitivity constraint, the further consideration of low cross-interference leads to a strict situation where the numerical iteration is hard to converge. To overcome this difficulty, three strategies are proposed, including a new description of the sensing areas, the modification of strain-gauge output constraints, and the iterative scheme with gradually shrinking bounds. Numerical examples demonstrate that these strategies perform very well and can ensure a robust iteration. Furthermore, the developed robust implementation is quite generic, which may be adopted in optimization problems with complex and strict constraints.