Development Of Multifunctional Animal Treadmill With Partial Weight Bearing Therapy

Spinal cord injury (SCI) is a common disease, which not only causes limb dysaesthesia, motor dysfunction and other physiological disability, but also brings a heavy burden to the family and society. Clinical research indicates that partial weight bearing therapy (PWBT) combined with epidural spinal cord stimulation (ESCS) could improve the locomotion performance of the subjects with incomplete spinal cord injury (ISCI). However, its underlying neural mechanism remains unclear. Therefore, the mechanism must be investigated by animal experiments for further clinical applications. This thesis intends to develop a multifunctional animal treadmill with partial body weight support (PBWS), which provides an advanced laboratory equipment for neural mechanism research of PWBT and its combination therapy.Firstly, the mechanical structure of the treadmill is designed to satisfy the requirements of the animal experiments. The treadmill consists of a running machine with continuous speed variation from 0 to 25 cm/s, a PBWS unit and a rehabilitation robotic arms. The PBWS unit can support the animal body to change the load on the hindlimbs. In addition, the rehabilitation robotic arms assists the animal to perform the stepping training and records the joint profile during locomotion for the motion analysis.In the thesis the treadmill control system is developed based on the microcontroller of C8051F020. In order to improve the accuracy and reliability, both the tension and angle sensors are used for the partial body weight support and achieve the closed-loop control of the running machine and rehabilitation robotic arms. The human-machine interface provides a convenient and reliable operation for the experimenter. The hardware of control system includes the main module, the signal acquisition and processing module and the motor driving module, which are all powered by the power supply unit. Silicon Laboratories IDE is used to design and debug the system software in order to achieve the data acquisition, the motor driving, the control algorithms, the human-computer interaction and communication.Then the mechanical structure of the rehabilitation robotic arms for rats is designed. The kinematics analysis and matlab-based kinematic simulation on the robotic arms are also presented. Moreover, the control algorithm of the robotic arms is presented.Finally, we conduct a pilot animal experiment to test the system functionality. The pilot test indicates that the developed treadmill can not only train the normal rats with different intensity, but also exert the PWBT and its combination therapy to treat the motor dysfunction for the ISCI rats. Meanwhile, the rehabilitation robotic arms could assist the SCI rats in the acute stage without autonomic movement to complete the treadmill training with partial weight bearing.