Design And Development Of The Embedded System For Portable Bicycle Trainer

With the development of the domestic economy and the improvement of life quality, people’s awareness of body-building is becoming stronger and stronger; Due to environmental pollution, traffic congestion and the impact of bad weather, bicycle trainer is loved by people as a simple, low-cost fitness equipment; However traditional bike trainer mostly use mechanical way to control resistance, it has the disadvantages of single function, complex resistance control, and lack of fitness index, so that it can not meet the needs of the market. In the “smart things” day, it is necessary to combine modern embedded technology and internet+ technology to develop an intelligent, portable, easy-to-use type of bike trainer, the trainer has the function of wireless and continuously-variable resistance adjustment, self generation, interconnection with smart phones and sports and exercise information monitoring and analysis, etc.In view of the shortcomings of the traditional bicycle device, this paper uses electromagnetic brake and dynamic braking principle to carry on the design and development of embedded and portable bike trainer control systems. The system realizes real-time wireless control of the trainer resistance and movement patterns. Meanwhile, it has the advantages of Bluetooth wireless control, continuously-variable resistance adjustment and fitness data monitoring and analyzing and so on. The research contents are presented as follows:Firstly, two types of non-contact resistance braking device based on the principle of electromagnetic brake and dynamic braking are designed to achieve no friction, no wear and no noise cycling resistance control.Secondly, the hardware system of the embedded control system for portable bicycle trainer is designed. The low-cost and high-performance ARM LPC1114 chip is selected as the core, and two types of resistance control circuit, multiple sensor interface circuits, radio control circuit, power circuit and other circuits are designed. PWM pulse width modulation is used to realize continuously-variable resistance adjustment, the acquisition and conversion of the speed, power, calories, temperature, heart rate and other information are realized through the various types of external sensors; Wireless control is realized based on low-power, highly reliable and scalable Bluetooth 4.0 communication chip CC2541.Then, the software system of the embedded control system for portable bicycle trainer is designed. Real-time operating system RTX is used as the main framework for program design, multi-mission design methods are used to design and realize Bluetooth communication, brake drag control, acquisition and conversion of speed, LED dynamic effects and temperature monitoring and other sub-task function modules. Therefore the architecture of system becomes modular, tasking and real-time, and the system is ensured stable, it’s function is easy to expand and improved at the same time.Finally, the research of hardware and software of the embedded control system for portable bicycle trainer is realized, and function and performance testing are carried on. The design and realization of two forms of the embedded system for portable bicycle trainer are verified via experiment, the trainer can adjust the resistance real-time, wireless and continuously, collect and calculate the heart rate, temperature, body-building time, real-time speed, riding distance and consumed calories, monitor and analysis the fitness motion data, it can meet the requirements of design and the needs of various types of body-building of users.The thesis researched on the design and development of embedded system for portable bicycle trainer, combined with the upper computer controller, the whole system realizes the wireless control and continuously-variable resistance adjustment, allowing users to access the data of fitness information, the number of fitness strength and comfort of the experience effect.