Development of Permanent Magnet Magnetic Field System of Vibroactuatror for Prosthetic Feedback Devices

According to World Health Organization data about one billion of people worldwide are disabled people. About one third of these people are people with mobility or movements impairments. First problem is that for that kind people high precision prosthetic devices with neural control and feedback are very expensive. Second problem almost all average price prosthetic devices have visual feedback system which loads user vision. To solve these two problems decided develop prosthetic devices with other kind of feedback systems: thermal, electrical, pressure, vibration...etc. For using vibration feedback, system vibration motors must work in wide range of frequency spectrum and produce controlled intensity in every frequency point. Unfortunately, nowadays-produced vibration motors cannot satisfy these requirements. In this paper represented 3d-printed voice-coil motor (VCM) magnetic circuit parameters changes depended on additional axial and radial ferromagnetic components and without them. Developed and tested VCM prototypes with different radial and axial ferromagnetic placement. Main measured parameters are magnetic flux density and derived current-force dependence linear domain. The best solution is without any iron shields. Axial shields has no effect on the induction, radial shield shunt magnetic field out of working zone of voice coil of the VCM.