Welcome to L-Type Motor repository

3. Motor control

Motor control

Motor control1、software-hardware2、Brief principle2.1、Hardware schematic diagram2.2、Physical connection diagram2.3、Principle of control3、Engineering configuration3.1、Notes3.2、Pin configuration4、Main FunctionMain Function4.1、User function4.2、HAL library functions5、Experimental phenomenon

This tutorial demonstrates how to control 4 310 motors using timers and print the encoder values via the serial port, where the KEY button controls the rotation mode of the motors.

1、software-hardware

STM32F103CubeIDE
STM32 robot expansion board
310 motor * 4
Type-C cable or ST-Link
Download or simulate the program of the development board

2、Brief principle

2.1、Hardware schematic diagram

2.2、Physical connection diagram

2.3、Principle of control

Motor speed and steering control: configure timer (TIM1 and TIM8) PWM output mode, change the duty cycle of PWM signal;

Motor encoder reading: Configure the encoder interface mode of timers (TIM2, TIM3, TIM4 and TIM5) to count the motor encoder signal.

310 motor

Type of motor	310 motor
Rated voltage of moto	7.4V
Encoder supply voltage	3.3-5V
Gear set reduction ratio	1：20
Number of magnetic ring lines	13 line
encoder type	Incremental Hall encoder with phase AB

Count value


Maximum count value={Reduction ratio*Number of encoder lines*4}=20*13*4=1040


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4: Represents the encoder frequency doubling
The rotation speed of the car can be calculated according to the count of rotation. This tutorial does not cover the conversion of speed

Motor drive

The STM32F103ZET6 integrates four AT8236 single-channel brush DC motor driver chips.

The input pins IN1 and IN2 control the output state of the H-bridge. The following table is the logical relationship between the input and output:

IN1	IN2	OUT1	OUT2	feature
0	0	Z	Z	Glide and sleep
1	0	H	L	Forward direction
0	1	L	H	Reverse direction
1	1	L	L	brake

When PWM control is used to implement the speed regulation function, the H-bridge can be operated in two different states: fast decay or slow decay.

IN1	IN2	feature
PWM	0	Forward PWM, fast attenuation
1	PWM	Forward PWM, slow decay
0	PWM	Reverse PWM, fast decay
PWM	1	Reverse PWM, slow decay

PWM period：T = 50us → f = 20KHz

T (s) = \frac{(A R R + 1) * (P S C + 1)}{T I M_C L K (H z)} = \frac{(3599 + 1) * (0 + 1)}{72000000 (H z)} = 0.00005 s = 50 u s

Encoder reading
The count value is obtained by reading the timer CNT register value directly.

The tutorial setup is count on TI1 and TI2 , set the encoder mode to 4x frequency, and the input signal is not reversed;


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Whether the counter counts up or down depends on the AB trust sign

3、Engineering configuration

3.1、Notes

Omitted project configuration: New project, chip selection, project configuration, SYS for pin configuration, RCC configuration, clock configuration, and project configuration content

The project cofiguration part, which is not omitted, is the key point to configure in this tutorial.


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Please refer to [2, development environment construction and use: STM32CubeIDE installation - Use] to understand how to configure the omitted part of the project

3.2、Pin configuration

GPIO

USART

Same configuration for TIM2, TIM3, TIM4, TIM5：TIM4 configuration is demonstrated here

TIM1 and TIM8 configuration are the same：TIM8 configuration is demonstrated here

4、Main Function

Detailed code can open the project file we provide, into the Bsp folder to view the source code.

Main Function

feature	Corresponding tutorial
key	3. Development board basic tutorial: Key control
Serial port	3, development board basic tutorial: serial communication

4.1、User function

function：Motor_Ignore_Dead_Zone

Function prototypes	int16_t Motor_Ignore_Dead_Zone(int16_t pulse)
Functional Description	The PWM signal dead zone is ignored
Input parameters	pulse：Value of pulse
Return value	Value of pulse

function：Motor_Stop

Function prototypes	void Motor_Stop(uint8_t brake)
Functional Description	All motors stopped
Input parameters	brake：The value is 0 or 1
Return value	None

function：Motor_Set_Pwm

Function prototypes	void Motor_Set_Pwm(uint8_t id, int16_t speed)
Functional Description	Set motor speed
Input parameters1	id：Motor ID
Input parameters2	speed：Motor speed
Return value	None

function：Encoder_Read_CNT

Function prototypes	int16_t Encoder_Read_CNT(uint8_t Motor_id)
Functional Description	Read the encoder count
Input parameters	Motor_id：Motor ID
Return value	Count value

function：Encoder_Get_Count_Now

Function prototypes	int Encoder_Get_Count_Now(uint8_t Motor_id)
Functional Description	Returns the total count of encoders counted since boot up (single way)
Input parameters	Motor_id：Motor ID
Return value	Count value

function：Encoder_Get_ALL

Function prototypes	void Encoder_Get_ALL(int *Encoder_all)
Functional Description	Returns the total count of encoders counted since boot up (single way)
Input parameters	Encoder_all：Points to the head of the encoder array
Return value	None

function：Encoder_Update_Count

Function prototypes	void Encoder_Update_Count(void)
Functional Description	Update the total count of the encoder
Input parameters	None
Return value	None

4.2、HAL library functions

The HAL library functions that were covered in the previous tutorial will not be covered


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For information on how to parse the HAL and LL libraries that are covered throughout this tutorial, check out the documentation under the STM32 Manual: STM32F1_HAL and LL Library_ User Manual

function：HAL_TIM_Encoder_Init

Function prototypes	HAL_StatusTypeDef HAL_TIM_Encoder_Init (TIM_HandleTypeDef htim, const* TIM_Encoder_InitTypeDef *sConfig)
Functional Description	Initialize the encoder mode for the timer
Input parameters1	htim：Timer handle address
Input parameters2	sConfig：The encoder initializes the configuration structure
Return value	HAL status value：HAL_OK、HAL_ERROR、HAL_BUSY、HAL_TIMEOUT

function：HAL_TIM_Encoder_MspInit

Function prototypes	void HAL_TIM_Encoder_MspInit(TIM_HandleTypeDef *htim)
Functional Description	Initialize the peripheral clock and GPIO for the timer encoder interface
Input parameters	htim：Timer handle address
Return value	None

function：HAL_TIM_Encoder_MspDeInit

Function prototypes	void HAL_TIM_Encoder_MspDeInit(TIM_HandleTypeDef *htim)
Functional Description	Cancel peripheral clock and GPIO initialization for the timer encoder interface
Input parameters	htim：Timer handle address
Return value	None

function：HAL_TIM_Encoder_Start

Function prototypes	HAL_StatusTypeDef HAL_TIM_Encoder_Start(TIM_HandleTypeDef *htim, uint32_t Channel)
Functional Description	Start timer encoder mode
Input parameters1	htim：Timer handle address
Input parameters2	Channel：The timer channel
Return value	HAL status value：HAL_OK、HAL_ERROR、HAL_BUSY、HAL_TIMEOUT

5、Experimental phenomenon

After downloading the program successfully, press the RESET button of the development board to open the serial debugging assistant to observe the phenomenon


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Program download can refer to [2, development environment construction and use: program download and simulation]

phenomenon：

Press KEY1：You can manually turn the four motors to observe the value of the encoder printed by the serial port;

Press KEY2：The motor turns forward and prints the encoder value on the serial port;

Press KEY3：The motor reverses and prints the encoder value on the serial port.


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The experimental phenomenon can be seen [Motor control _ Experimental Phenomenon.MP4]

Basic use of ultrasonic steering gear gimbal

OLED display light sensitivity value