  This work presents an on-going investigation of the control of a pneumatic
soft-robot actuator addressing accurate patient positioning systems in maskless
head and neck cancer radiotherapy. We employ two RGB-D sensors in a sensor
fusion scheme to better estimate a patient's head pitch motion. A system
identification prediction error model is used to obtain a linear time invariant
state space model. We then use the model to design a linear quadratic Gaussian
feedback controller to manipulate the patient head position based on sensed
head pitch motion. Experiments demonstrate the success of our approach.
