Abstract:
The measurement performances of the parallel-type six-axis accelerometer are related to the limb layout of its sensing mechanism. If the coordination equations of outputs of the sensing mechanism cannot form a closed chain structure, the fault tolerance performance of the accelerometer is poor, restricting the development of multi-dimensional motion sensing technology. Therefore, it is necessary to analyze the formation conditions of the coordinated closed chain structure of the parallel-type six-axis acceleration sensing mechanism and the relationship between the coordination equations and the limb layout. In order to achieve this goal, firstly, taking the case that the moving spherical joints are located at the top of the mass block as an example, the limb length equations and their coefficient matrix are derived. Secondly, the general formula of the coordination equation satisfying the closed chain structure is derived, and combined with the coefficient matrix, the limb layout conditions that can form the closed chain structure are found. Then, according to the limb layout conditions, a "12-7" topology parallel-type six-axis acceleration sensing mechanism is synthesized. Finally, the limb layout law is extended to the case where the moving spherical joints are located at the midpoint of the mass block edge, and two "12-8" topology parallel-type six-axis acceleration sensing mechanisms are synthesized. It is verified that the coordination equations of the three new configurations can form closed chain structures, which shows that the proposed configuration synthesis method is effective.