On-Off Tremor Suppression Orthosis with Electromagnetic Brake

Pathological tremor is a common neurological movement disorder characterized by involuntary rhythmic oscillation of body parts. Available treatments are often insufficiently effective or are accompanied by severe side effects. This work proposes a lightweight, portable elbow tremor suppression orthosis using an electromagnetic brake (EB) with on-off actuation scheme. The device reduces tremor amplitude and could potentially be donned under clothes. At this stage of the project, the focus is on action tremor (postural) such as essential tremor. The elbow joint is commonly affected by tremor; it can be modelled as a single Degree Of Freedom (DOF) joint and was selected to test our hypothesis and prototype. The orthosis is actuated by an (EB). The algorithm alternates between full suppression and no suppression, and relies on the high frequency nature of tremor relative to the frequency of Activities of Daily Living (ADL). A MEMS gyro signal is processed to assess the tremor component. The system successfully reduces tremor amplitude with over 88% of tremor signal power reduction.