Development of Compact 3-Degree-of-Freedom Oscillatory Actuator

Haptics applications are receiving increasing attention in entertainment, medical support systems, and various industries. Three-dimensional (3D) haptics is important to provide users real experiences. Conventional haptic devices consist of many motors and mechanical elements grounded in an environment. Therefore, they are large in size and heavy. Haptic devices using asymmetric vibrations can display illusion forces with mobile structures. However, they need additional structures (comprising actuators) to generate a 3D illusion force; however, the operational mechanism becomes complex. To solve this problem, we propose the use of a 3-degree-of-freedom (3DOF) oscillatory actuator that can generate a 3DOF vibration using only one actuator. This study describes the basic characteristics and operating verification of the 3DOF oscillatory actuator. The static thrust characteristics are quantified and analyzed using a finite element method. The dynamics are calculated based on numerical simulations using a dynamic model. The prototype’s experimental results show that the 3DOF actuator can generate 3DOF vibration.