Development of cylindrical magnetorheological fluid brake for virtual cycling system

Dementia is one of major concerns in the aging societies. There are many evidences that aerobic exercises show positive effects in older patients of dementia. Our goal is to develop a virtual cycling system which can control wide range force feedback from its pedals, and provide safe experiences of cycling for the elderly people to prevent from the dementia. A main purpose of this paper is the development of a magnetorheological fluids brake (MRB) with a rotational cylinder (cylindrical MRB) for force control of the cycling system. We proposed a structure with a rotor cylinder and multiple coils to make a wide range of magnetic flux density on the surface of cylinder for the effective MR effect. The estimated torque and experimental results were compared. Although, the results show errors at off-state of the brake due to the friction of an oil seal, we could develop the cylindrical MRB whose maximum torque is about 10 Nm.