PID
Guide
API
Guide
API

Features

default

struct Pid pid_new_with_default(float kp, float ki, float kd);

创建默认PID控制器

  • derivative = (previous - error) / dt
  • integral += ((error + previous) / 2) * dt

Args

  • kp 比例增益系数
  • ki 积分增益系数
  • kd 微分增益系数

Example

#include "pid/pid.h"
struct Pid pid = pid_new_with_default(1, 0, 0);
pid_update(&pid, 0, 0, 1);

integral-decay

struct Pid pid_new_with_integral_decay(float kp, float ki, float kd, float integral_decay_factor);

创建带积分衰减的PID控制器

  1. integral *= integral_decay_factor
  2. integral += ((error + previous) / 2) * dt
TIP

积分最大值将变为原来的 1 / (1 - integral_decay_factor)，可能存在恒定误差

Args

  • integral_decay_factor 积分衰减因子
    • integral_decay_factor = 1 则完全不会衰减
    • integral_decay_factor = 0 则不积分

Example

#include "pid/pid.h"
struct Pid pid = pid_new_with_integral_decay(1, 0, 0, 0.9);
pid_update(&pid, 0, 0, 1);

integral-clamp

struct Pid pid_new_with_integral_clamp(float kp, float ki, float kd, float integral_clamp_bound_min, float integral_clamp_bound_max);

创建带积分限幅的PID控制器

  1. integral += ((error + previous) / 2) * dt
  2. integral = clamp(integral, integral_clamp_bound_min, integral_clamp_bound_max)
TIP

如果 integral_clamp_bound_max设置的过小，将会造成不能达到目标

Args

  • integral_clamp_bound_min 积分最小值
  • integral_clamp_bound_max 积分最大值
    • min must less than max

Example

#include "pid/pid.h"
struct Pid pid = pid_new_with_integral_clamp(1, 0, 0, -300, 300);
pid_update(&pid, 0, 0, 1);

integral-separation

struct Pid pid_new_with_integral_separation(float kp, float ki, float kd, float integral_separation_error_threshold_lower, float integral_separation_error_threshold_upper);

创建带积分分离的PID控制器

  • if (lower < error && error < upper) integral += ((error + previous) / 2) * dt

Args

  • integral_separation_error_threshold_lower 积分分离下限，当 target - actual 大于这个值
  • integral_separation_error_threshold_upper 积分分离上限，当 target - actual 小于这个值

Example

#include "pid/pid.h"
struct Pid pid = pid_new_with_integral_separation(1, 0, 0, -100, 100);
pid_update(&pid, 0, 0, 1);

integral-sliding-window

struct Pid pid_new_with_integral_sliding_window(float kp, float ki, float kd, float finite_time);

创建带积分滑动窗口的PID控制器（积分定长时间 t0 = finite_time）

∫t−t0te(t)dt\int_{t - t_0}^{t} e(t) dt

Args

  • finite_time 积分定长时间（从当前往前积分 finite_time）单位为秒

Example

#include "pid/pid.h"
struct Pid pid = pid_new_with_integral_sliding_window(1, 0, 0, 10);
pid_update(&pid, 0, 0, 1);