Research On Dosing Precision And Security Of Insulin Pump

Diabetes is one of the three diseases which threat to human health, and diabetes patients have reached 10% of the total number of population. The injection of insulin is one of the most efficient methods of insulin therapy, and insulin pump is the precise injecting device, which is the lowest degree of patient pain. However, this type of device is monopolized by foreign products. To develop an insulin pump with performance of high dosing precision, high safety which has independent intellectual property rights is full of social significance and economic value. The topic of this thesis is to design an insulin pump, and mainly focus on the ways of the dosing precision and system security promotion.First, the requirements of dosing precision was analysed and the goal parameters of insulin pump was determined according to the characteristics of diabetes, the overall scheme which named piston type was put forward. The specific parameters of the motor and mechanical transmission were confirmed in term of objective parameter. In order to get the influence of injecting precision, the mathematical mode of insulin pump electromechanical transmission system was established. For the sake of the accuracy of insulin pump, a PID system controller was set up. Then the parameter of PID system controller was designed using 4:1 ratio method. At last, the correctness of the system model parameter was verified.In order to promote safety of system, a project on the part of software and hardware was designed, which can eliminate the influence on threading factors, then a detailed plan was proposed. The security design facing hardware system includes: temperature detecting module, pressure detecting module, over-current detecting module, etc. The security design facing software includes: protecting methods in programming, in algorithm as well as dealing with abnormal condition combined with hardware, etc.The experiments with respect to dosing precision and security system were employed after the insulin pump prototype experimental platform was built. The dosing precision experiment includes: the experiment of actual line number compared with given line number, the relationship between code number and practical doses, system controller parameter validation and dosing precision experiment. The availability of system controller design and the dosing precision was verified by this experiment. The security system experiment includes: infusion pressure security experiment, human error operating security protection experiment and sensor state experiment. The design of hardware and software facing security system was confirmed to be correctness and significance.