Stepper Motor Control System

This document explains the implementation of a stepper motor controller used in robotics applications. The system provides comprehensive control over stepper motors with built-in safety features and precise movement control.

1. Motor Configuration

The motor controller is initialized with specific parameters for each motor:

CtrlStepMotor::CtrlStepMotor(CAN_HandleTypeDef* _hcan, uint8_t _id, bool _inverse,
                             uint8_t _reduction, float _angleLimitMin, float _angleLimitMax)

Each motor has:

• A unique ID for communication
• Direction settings (normal or inverse)
• Gear reduction ratio
• Angle limits for safety

2. Communication Protocol

The system uses CAN bus communication with a specific message format:

txHeader = {
    .StdId = 0,
    .IDE = CAN_ID_STD,
    .RTR = CAN_RTR_DATA,
    .DLC = 8,
}

This protocol enables:

• Unique message identification
• Standard data format
• Real-time communication
• Status feedback

3. Basic Control Functions

Core Control Methods

void CtrlStepMotor::SetEnable(bool _enable)
void CtrlStepMotor::SetCurrentSetPoint(float _val)
void CtrlStepMotor::SetVelocitySetPoint(float _val)
void CtrlStepMotor::SetPositionSetPoint(float _val)

These functions provide fundamental control:

• Enable/disable motor operation
• Current control for torque adjustment
• Velocity control
• Position control

4. Advanced Movement Control

Sophisticated Motion Control

void CtrlStepMotor::SetPositionWithVelocityLimit(float _pos, float _vel)
void CtrlStepMotor::SetAcceleration(float _val)

These methods enable:

• Position control with speed limits
• Acceleration/deceleration control
• Smooth movement profiles

5. Safety Features

Protection Systems

void CtrlStepMotor::SetCurrentLimit(float _val)
void CtrlStepMotor::SetEnableStallProtect(bool _enable)
void CtrlStepMotor::GetTemp()

Safety mechanisms include:

• Current limiting for overheating prevention
• Stall protection
• Temperature monitoring
• Automatic shutdown on fault conditions

6. Motor Tuning (PID Control)

PID Parameters

void CtrlStepMotor::SetDceKp(int32_t _val)
void CtrlStepMotor::SetDceKi(int32_t _val)
void CtrlStepMotor::SetDceKd(int32_t _val)

PID control enables:

• Precise position control
• Error elimination
• Oscillation reduction
• Optimal response characteristics

7. Configuration Management

System Configuration

void CtrlStepMotor::ApplyPositionAsHome()
void CtrlStepMotor::SetEnableOnBoot(bool _enable)
void CtrlStepMotor::EraseConfigs()

Configuration features:

• Home position setting
• Boot behavior configuration
• Factory reset capabilities
• Persistent settings storage

8. Angle Calculations

Position Control

void CtrlStepMotor::SetAngle(float _angle)
{
    _angle = inverseDirection ? -_angle : _angle;
    float stepMotorCnt = _angle / 360.0f * (float) reduction;
    SetPositionSetPoint(stepMotorCnt);
}

This system handles:

• Angle to step conversion
• Direction compensation
• Gear ratio calculations
• Precise positioning

Key Features Summary

1. Real-time Control

   • CAN bus communication
   • Immediate response
   • Status feedback

2. Safety Systems

   • Current limitation
   • Temperature monitoring
   • Stall protection
   • Emergency stop capability

3. Movement Control

   • Precise positioning
   • Velocity control
   • Acceleration management
   • Smooth motion profiles

4. Configuration Options

   • Persistent settings
   • Boot behavior
   • Home position
   • System calibration

5. Protection Mechanisms

   • Overheating prevention
   • Stall detection
   • Current limiting
   • Position limits

System Benefits

The implementation ensures:

1. Precise movement control through PID tuning
2. Safe operation with multiple protection layers
3. Flexible configuration for different applications
4. Reliable communication through CAN bus
5. Comprehensive status monitoring
6. Easy integration with larger systems