【Training Camp】Four-Legged Dog

Thanks to the teachers at Lichuang EDA and Chuanzhi Education for their teaching and guidance. I was fortunate enough to learn about the MCU of HiSilicon 3861 and Hongmeng OS during the process of being a dog. It was a great experience! However, personal abilities are limited and free time is tight, so some of them can only be gradually improved by themselves. The main control of the board is hi3861, the servo control is pca9685, the status detection is mpu6050, the serial communication is ch340c+TypeC interface, and the power supply is 12V lithium battery , the MG995 with a servo drive of about ten yuan, the main frame is a servo bracket + aluminum plate + acrylic; at first, because the LDO was used to directly convert 12V to 7.4V in the servo, the board was too hot, so a DCDC module was added at the back (it is recommended to do it directly in board), first reduce the 12V to 9.5V and then reduce the LDO to 7.4V. It is much better. If the battery is out of power for a long time, you don’t have to worry about the board exploding; the 5525DC female socket can be directly replaced with the 5521DC female socket, so There is no need to change the lithium battery cable. It is recommended to put a power switch on the board, which will be more convenient. Regarding the software, the author is lazy (it is recommended to do it carefully) and directly generate it quickly according to the center of gravity of the mechanical structure using the software provided by Chuanzhi Education. The coordinate point of the dogleg and the angle of the servo; simply encapsulate the read and write of pca9685 and mpu6050 on the i2c bus, and then call it directly in the specific gait task and data acquisition task; the specific process: power on -> initialize io boot Foot -> Initialize pca9685 and mpu6050 on the i2c bus -> Initialize the settings of the wifi interface -> Open the socket and wait for the mobile phone to connect (stomping the foot to indicate connection) -> Interact instructions and data, and you can adjust the thread priority according to your own needs. , add read-write locks and task synchronization; areas to be improved: ADC collects battery voltage, transplants the mpl library of mpu6050, and directly uses inverse kinematics solution + mpu6050 to fine-tune the dog's gait (the author spent a lot of time on this issue) ; Because the author is not familiar with hi3861, I initially wrote driver debugging on stm32, but the development environment is different. It is recommended that debugging directly on hi3861 will save more energy;