Design Of Robotic Wheelchair Drive Control And Sitting Posture Balance Detection System

With the aging of the population,due to the aging of diseases and body functions,a large number of patients with motor defects and perception disorders.How to provide reliable transportation tools for them is a hot research topic at present.As a travel assistance device,the robot wheelchair can meet the needs of users to travel.Its reliability and comfort are the key points of this study.When users with limited perception,such as hemiplegia patients,use wheelchairs,if they maintain poor sitting posture for a long time,it will cause harm to the human body,or even aggravate the condition.In this paper,the human-computer interaction mode based on Hall joystick is reserved,and the interface of head posture and gesture interaction is reserved.The driving control system design of robot wheelchair is completed,and the sitting posture balance detection system is combined with the wheelchair to realize the detection and display of human sitting posture.The main results are as follows:(1)The robot wheelchair drive control system is divided into upper control and lower control,which communicate through serial port.It mainly includes the following:(1)The upper control adopts the man-machine interaction mode of joystick,and takes the single chip STM32F103RCT6 as the core,including the acquisition and processing of joystick signal,and the fault state display,etc.The human-computer interaction part is responsible for collecting Hall joystick position and button configuration information,controlling the movement of the robot wheelchair in real time,and displaying the state information of the wheelchair.In order to improve the responsiveness of the wheelchair in the state of motion,the braking can not deviate from the user's desired direction,focus on the design and optimization of the difference calculation method,in the state of motion,according to the user's desired state and the actual running state,divided into general state and special state of motion;When parking,different control strategies are used according to whether the left and right wheel directions are the same.The effect was verified by experiments.(2)The down control is a double motor drive module,with STMS32F13VCT6 as the core,including the power circuit,motor drive circuit,motor speed measurement circuit,a variety of fault detection circuit.The dual motor drive module is responsible for receiving and executing the control information of the human-computer interaction module,and providing real-time feedback of the operation information.In order to reduce the time complexity of the program and improve the running efficiency of the motor,the finite state machine is used to control the motor,which is divided into 7states according to the start,stop and fault,and each state can be switched between each other.(2)Based on the structure of the robot wheelchair,the human sitting posture detection is combined with it,and the installation position of IMU on the human body and the wheelchair is selected to realize the detection of the posture of the wheelchair and the human body.It is divided into lower computer part and upper computer part:(1)Under a machine part includes hardware selection,sensors,data acquisition,set up more than a master from bluetooth communication,using two bluetooth from machine with six axes inertial sensor nodes,the original attitude data real-time acquisition,way to pass data to the notification via bluetooth bluetooth host,by bluetooth host the data collected through a serial port is passed to the PC.(2)The upper computer part mainly includes the attitude calculation and image display.Attitude fusion algorithm is used to solve the attitude information,and then Open GL graphics library is used to display the real-time image according to the attitude information and the human body model drawn in advance.