Obiective To descript the method and the equipment of implantable single-point electric stimulation which is designed to continionsly and effectively treat the chronic diseases that harm the people's health. Methods The system is constructed with two parts, outside power transfer and implanted power receiver. The bypass capacitor of transistor and transformer inductor make up of power transmitter, which is half series resonant. With using transeutaneous power transform, the efficiency of this transform is studied. Experiments choose proper transmitting parameters: transformer winding is a 20 turns hollow coil of 35mm diameter, and the frequency is 150-200 kHz; the receiver winding is a 100 turns hollow coil of 10ram diameter. Results Finally the completed prototype of the system and the receiver can generate about 5-10 mA current to stimulation tissue with 5mm gap between receiver and radiator, which meets the requirement of application.ConclusionThis instrument can be used in all kinds of single-point stimulation experiment.

Objective To develop a programmable neuromuscular electrical stimulation system as a potential countermeasure for muscle atrophy in long-term microgravity.Methods The system was mainly composed of a controllable constant current pulse generator,wires and skin electrodes.To meet the requirements of stimulating recipes selection,the stimulating parameters could be adjusted independently and the combinatorial output of different stimulating phases should also be achieved.Results The system worked well with high accuracy outputs.The sensation,contraction,tetany and pain thresholds of all the 5 waveforms stimulating signals were measured.For different stimulating waveforms,thresholds of each state were different and the subjective sensations induced by same stimulating amplitude were dissimilar.Conclusion The developed system providing powerful programmable and accurate stimulating signals,is convenient for the selection and verification of stimulating recipes and can be used as an instrument platform for study of electrical stimulation to prevent muscle atrophy in microgravity.Volunteer experiments have proved its validation for function of muscle contraction and provide primary basses for the optimization of stimulating recipes.