Implementation of indoor positioning system for domestic robots based on drawing board program

With the rapid economic development, people's pace of life is getting faster and faster. Domestic Robot (DR) has been favored by more urban citizens because it can replace people to complete domestic service work. At present, low-end DR mainly uses single input functions such as cleaning and other repetitive operations, and lacks interaction with users; although high-end DR has complete functions, it is expensive and not easily accepted by general users. The system designed in this paper interacts with users through the route drawing program of the host computer, and realizes the indoor positioning control (Indoor Positioning Control) of DR in a low-cost and convenient way, which has good practicality.
1 System Structure
The overall architecture of the system is divided into two parts: the host computer information sending system and the robot subsystem. The host computer uses the route drawing program written in VB as the visual control platform to realize the functions of loading the house layout, drawing the travel route, extracting coordinates, calculating route information and wireless transmission. The robot processing subsystem uses FPGA chip as the core processor, combining SoPC technology and Verilog hardware description language to complete the configuration of FPGA chip, and Nios II soft core to realize wireless reception of route information and extract route information. Use Verilog hardware description language to build the PWM control module of the motor and steering gear, control the motor and steering gear to complete the route driving. The system block diagram is shown in Figure 1.

2.1.2 Serial port wireless module
The PC route drawing program packages the information and transmits it to the wireless module CC1100-232 through the serial port and then sends it out. CC1100 is a high-performance wireless communication chip of TI. It adopts serial port working mode and can work in the 433 MHz/868 MHz/915 MHz public frequency band. The serial port rate is 1.2 Kb/s~38.4 Kb/s. It has a wide range of applications in wireless sensors, home automation, robot control and other fields.
2.2 Robot subsystem
The function of the robot subsystem is to realize the reception and execution of route information. It consists of FPGA processor, CC1100-232 wireless module and robot model.
2.2.1 Robot model
The accurate realization of the micro-element route requires the robot to walk accurately according to the route information. The key to the design of the robot model lies in the design of the moving part. The robot moving part of this system consists of two driven wheels, a driving wheel with a code disk, a photoelectric tube TCRT5000 and a motor module. The motor module of the driving wheel consists of two parts: a 130 motor and a 5010 servo. The motor and the servo are installed on the driving wheel. The motor drives the driving wheel to rotate, and the servo drives the driving wheel to rotate. The PWM wave can control the rotation of the motor and the servo. Adjusting the duty cycle of the PWM wave can change the motor speed and the rotation angle of the servo. The driving wheel is equipped with a code disk and a photoelectric tube TCRT5000. The combination of the two can accurately record how many code grids the driving wheel has rotated.