| The stroke is a common disease in our country. After the treatment of the patients with stroke,there are hemiplegia and other sequelae. It has brought a very serious economic and psychological burden to the patient and the patient’s family. Functional electrical stimulation(FES) device is the main therapy to assist walking for patients with hemiplegia after stroke at those years. But Functional electrical stimulation device has obvious defects in use, for example, a single channel or dual channel stimulation do not have the real features of the functional electrical stimulation,the function is too simple and the effect is not significant. For the multi-channel stimulate, the device is bulky and complex at the course of operation. And it is portable. Therefore, the study of portable and functional electrical stimulation (FES) devices is very important.Based on the functional electrical stimulation, this topic has designed a kind of hemiplegic physical therapy instrument with three channels. The operation is simple and it is portable. The instrument has three channels, simulate the three channelstiming pulse at the time of contracting muscles, output low frequency electric pulse stimulation and simulate gluteus maximus, musculi tibialis anterior and musculi quadriceps femoris coordinately. So that it can effectively contract muscle according to certain rules, produce walking action, improve the walking posture of the hemiplegic patients, and improve the stability of walking. The three channel hemiplegic physical therapy instrument can adjust the intensity of the stimulation signal according to the patient’s response and effect. It can reliaze the independent of each channel and the improvement of the function. It includes static practice mode and dynamic walking mode. At static practice mode , it can prevent muscle from atrophying by stimulate muscle. In the dynamic walking mode, it can improve the patient’s posture of walking by stimulating gluteus maximus,musculi quadriceps femoris and musculi tibialis anterior. In the dynamic walking mode, collecting the heel pressure signal by pressure sensor instrument as the starting signal of the stimulation, the purpose is to avoid mutual interference.In this paper, the design of the core control circuit board of the three channel hemiplegic physical therapy instrument is completed. Followed by,on base of the hardware platform ,using PIC24FJ256 as the control core, and using C language as the programing language to simulate the time sequence of the three muscles in the cycle and to design procedure to achieve a better effect.Then, the function verification is carried out by oscilloscope to meet the expected requirements.Finally, developing the three channels hemiplegic physical therapy instrument. |
