A biologically inspired joint model to enhance understanding of spasticity

Persons with cerebral palsy often experience spasticity. This is believed to result from hypersensitivity to the position and velocity feedback of joint position. In order to better understand and improve the effects of biomechanics under these conditions, we have chosen to emulate the spasticity of muscles by constructing a physical model of a joint with agonist and antagonist muscles operating under linearized control. Utilizing LabVIEW software, McKibben air muscles and Merlin stretch sensors, we will be able to incorporate a PD controller to study the reflex loops under various levels of feedback sensitivity. The feedback mechanism, similar to proprioceptive muscle spindle feedback, will be based on the Input given from the stretch sensors to achieve a desired Inputted angle. After the air muscles demonstrate spasticity, investigation into the control of spasticity can be improved.