Design of a brain controlled hand exoskeleton for patients with motor neuron diseases

Patients suffering with motor neuron diseases (MND) are characterized by their inability to control essential voluntary muscle activity. This situation may lead to what is known as Locked-in syndrome (LIS). As the name suggests, LIS describes the state of being locked inside a paralyzed body with a functioning mind. With recent advances in robotics and signal processing technologies, patients with motor neuron disease may be able to partially overcome their disability and regain some control over their external environments. In this paper, we propose a design for brain´s controlled hand exoskeleton. The proposed system uses a dual loop control, namely the brain-hand control and a local (hand) force control. The hand exoskeleton design consists of three main parts: four fingers with a three-layered sliding spring mechanism, an extension to fix the thumb of the patient and the main body which connects all the fingers with the linear actuator. The proposed system is implemented and tested successfully. Two actions are performed, namely grasping and releasing a light foam ball. After a training period, the brain-controlled exoskeleton was able to perform the two actions accurately and smoothly.