The LLD is a notional medical device that treats unequal length of paired limbs and is attached to the bone after the osteotomy. Our group is developing an implantable extramedullary device with a patient-specific feedback control mechanism to optimize limb lengthening procedure. During this procedure, bone callus and soft tissues around the callus generate resistive forces that often indicate possible complications. In order to address these complications, I am working on the design and validation of the feedback control mechanism using an existing distraction prototype. The prototype is motor driven with a lead screw mechanism. The prototype is evaluated by an MTS load test machine which simulates the expected distraction forces.
xPC System and MTS Testing Setup
Initially, I used a Simulink xPC real-time control system to implement the control algorithm. However, that system consists of a host computer, a target computer and other components, leading to large size and limiting its mobility. To reduce that limitation, I am implementing the same functionality in an embedded microcontroller to drive the system. Throughout this process, I have configured the power electronics and circuit components, and made a printed circuit board. To interface the systems, I am also developing wireless connection between the device and a control computer. A draft paper had been submitted to ASME Journal of Medical Devices. Another paper with more research work will be submitted to a different journal by the end of my Master’s study.
Microcontroller Setup with Arduino Mega Board, Encoder Shield, Motor Shield and Bluetooth Module
More details can be found here.