pid.h File Reference

PID control and motor control API for robotic hand fingers. More...

#include "Constants.h"

Go to the source code of this file.

Classes
struct	PID_t
	PID controller state structure. More...

Functions
void	PositionControlFinger (uint32_t enc, uint32_t target, PID_t *pid, int pwm_channel, int phase_pin, float dt)
	Perform PID-based position control for a single finger motor.
void	SetPhase (float u, uint32_t motor_phase_pin)
	Set motor direction based on signed control effort.
bool	HomeFinger (uint32_t enc, uint32_t home_target, int pwm_channel, int phase_pin)
	Home a single finger motor to a reference position.
void	PID_Reset (PID_t *pid)
	Reset a PID controller's internal state.
void	InitPIDs ()
	Initialize all PID controllers used by the robotic hand.

Variables
Global PID controller instances
PID controllers for each finger and palm motor.
PID_t	pid_thumb
PID_t	pid_index
PID_t	pid_middle
PID_t	pid_ring
PID_t	pid_pinkie
PID_t	pid_palm

Detailed Description

PID control and motor control API for robotic hand fingers.

This header defines:

• The PID controller data structure
• Public functions for PID initialization, reset, and stepping
• Motor control helpers for homing and position control

Implementation details are provided in pid.cpp.

Function Documentation

HomeFinger()

bool HomeFinger	(	uint32_t	enc,
		uint32_t	home_target,
		int	pwm_channel,
		int	phase_pin )

Home a single finger motor to a reference position.

Drives the motor toward a known home encoder value using a proportional controller until the error falls below ::HOMING_THRESHOLD.

Parameters

enc	Current encoder reading.
home_target	Desired home encoder value.
pwm_channel	LEDC PWM channel controlling the motor.
phase_pin	GPIO pin controlling motor direction.

Returns

true if the finger is homed, false otherwise.

InitPIDs()

void InitPIDs

(

)

Initialize all PID controllers used by the robotic hand.

Sets gains and output limits for all fingers and palm.

PID_Reset()

void PID_Reset

(

PID_t *

pid

)

Reset a PID controller's internal state.

Clears the integral accumulator and previous error term.

Parameters

pid	Pointer to PID controller structure.

PositionControlFinger()

void PositionControlFinger	(	uint32_t	enc,
		uint32_t	target,
		PID_t *	pid,
		int	pwm_channel,
		int	phase_pin,
		float	dt )

Perform PID-based position control for a single finger motor.

Computes the control effort using PID, sets motor direction, enforces a minimum PWM threshold, and applies the PWM output.

Parameters

enc	Current encoder reading.
target	Desired encoder target value.
pid	Pointer to PID controller for this finger.
pwm_channel	LEDC PWM channel controlling the motor.
phase_pin	GPIO pin controlling motor direction.
dt	Control loop timestep in seconds.

SetPhase()

void SetPhase	(	float	u,
		uint32_t	motor_phase_pin )

Set motor direction based on signed control effort.

Uses the sign of the control signal to determine the motor rotation direction via the phase pin.

Parameters

u	Signed control output.
motor_phase_pin	GPIO pin controlling motor direction.