Design Of Self-generating And Electromagnetic Damping Control System For Fitness Equipment

Strength qualities can reflect the level of physical qualities,and strength training plays a positive role in maintaining a strong body and sufficient energy.The transmission system of traditional fitness equipment,such as electric treadmills and bicycle fitness machines,is difficult to achieve real-time resistance change according to a preprogrammed curve with time or speed.Therefore,it is impossible to automatically simulate the effect of strength training with rapid resistance changes,such as changes in gust strength,slope height,etc.This thesis combines the development status and existing problems of domestic and foreign fitness equipment to develop a self-generated and electromagnetic damping control system.This system does not require external power supply,has intelligent charge/discharge functions,and can adjust resistance output in real time.The system uses a PMSG(permanent magnet synchronous generator)as a resistance source,which can replace complex mechanical resistance structures and some electric resistance structures.It is widely used in fitness machines such as treadmills and bicycle trainers.The research work is as follows:(1)According to the usage scenario,the generator needs to meet the characteristics of small size and large energy density.This thesis uses ANSYS finite element software to model and design the PMSG,and carries out the two-dimensional static magnetic field and transient magnetic field through simulation analysis.Moreover,the principle model of the PMSG is completed.Then,combined with the characteristic that the output resistance needs strong followability,several typical PID algorithms are simulated and compared,and the appropriate resistance adjustment algorithm is selected for the system.(2)The hardware circuit principle of the system is studied and analyzed in detail,and the modular design is used on the circuit to improve the safety performance.Specifically,the following modules are designed on the controller: the liquid crystal display,intelligent charging and discharging,key scanning and data acquisition and storage,etc.The following modules are designed on the driver: rectifier inverter,input control,power regulation and power feedback and other circuits.(3)Software design of the system.In the μC/OS-II embedded operating system,driver softwares of LCD,SD card,key control and other peripherals were developed.Through task division and design,the functions of program upgrade,information interaction and motion mode scheduling were realized.(4)The performance of the system was verified.Collaborated with the manufacturer to develop and customize a three-phase AC PMSG.Using this generator to build an experimental platform for this system.First,the controller and driver peripheral functions were tested in detail,and then the entire system was separately Tests in curve,transverse damping and damping curve mode.The results show that the strength fitness device developed by this system can accurately output the resistance following the set curve,and has a good strength training effect to meet the design requirements.