Dumbbell Motion Detection And Energy Consumption Calculation System Design And Implementation Based On MEMS Sensor

To meet the needs of users to do dumbbell exercises at home,this paper designs and implements a dumbbell motion detection and energy consumption calculation system based on MEMS sensor.Different from the exercise in the gym,fitness trainer can give details of the exercise scheme,and correct the wrong action,users exercise at home have to master the muscle to be exercised and the effect of exercise all by themselves.This system samples and identifies the dumbbell motions,analyzes the muscles that is exercised,and calculate the energy consumption of the user,thus to help the user to do the dumbbell exercise correctly and effectively.This system is divided into motion sampling side and computer side,and they communicate via Bluetooth.In order to sample the motion data,this paper designs and realizes the motion sampling side first.Motion sampling side is mainly responsible for sampling data,including three-dimensional accelerations and three-dimensional angular velocities data,and then calculates the Euler angle,provides data for motion detecting and energy consumption which will be done on the computer side.Motion sampling side is comprised of movement motion sampling circuit and ordinary adjustable dumbbell,fixes the circuit to the dumbbell,so we can sample the movement of the dumbbell.Motion sampling circuit is mainly composed of microprocessor,motion sensor,Bluetooth RF,I/O and power supply.The microprocessor adopts in STM32F103C8T6 microcontroller which has the ARM Cortex-M3 core;The motion sensor adopts in the MPU-9250 nine-axes Motion Tracking device,by using the DMP in the sensor,we can do the attitude estimation to provide the attitude data;The Bluetooth RF adopts in USR-BLE101 module,the module supports BLE 4.1 protocol;The I/O parts including buttons,LED,as well as the extended interface and so on,the power supply adopts CR2032 button battery,by the flexible mechanism of sleep and wake up of the processor and sensor,we can effectively save energy.The motion sampling side packages the sampled motion data with the predefined frame format,and then sends to the computer side via BLE 4.1.The Computer side is mainly responsible for dumbbell motion detection and energy consumption calculation,including motion detection method and energy consumption calculation method.This paper puts forward a motion detection method based on MEMS sensor,the method reads the three-dimensional accelerations and angular velocities of the real-time sampled data,and then Pearson correlation coefficient between the sampled data and the vectors in the feature database is calculated after acceleration decomposition,filtering,motion cycle determination and normalization.Thereby,the specific motions can be detected,and the repetitive motions can be counted.In this paper,6 kinds of common dumbbell motions detection experiments are carried out to verify the effectiveness of the motion detection method,and the average detection rate is 94%.Energy consumption calculation method analyzes the part of muscle each dumbbell motion is exercised,at the same time,through the calculation of the kinetic energy of the dumbbell,analyzes the consume of energy(heat)of each motion,then census the energy consumption of each part of muscle and the user's total energy consumption.By the dumbbell motion detection and energy consumption calculation system,users can accurately grasp their muscle exercise situation,thus do the dumbbell exercises more scientifically.