From e553087d10e7187c12e5e0f28937585a732a46da Mon Sep 17 00:00:00 2001 From: Anton Babushkin Date: Sun, 1 Sep 2013 20:17:24 +0200 Subject: pid.limit != 0 fix --- src/modules/systemlib/pid/pid.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'src/modules/systemlib/pid') diff --git a/src/modules/systemlib/pid/pid.c b/src/modules/systemlib/pid/pid.c index 562f3ac04..739503ed4 100644 --- a/src/modules/systemlib/pid/pid.c +++ b/src/modules/systemlib/pid/pid.c @@ -51,6 +51,8 @@ #include "pid.h" #include +#define SIGMA 0.000001f + __EXPORT void pid_init(PID_t *pid, float kp, float ki, float kd, float intmax, float limit, uint8_t mode, float dt_min) { @@ -168,7 +170,7 @@ __EXPORT float pid_calculate(PID_t *pid, float sp, float val, float val_dot, flo // Calculate the error integral and check for saturation i = pid->integral + (error * dt); - if ((pid->limit != 0.0f && (fabsf((error * pid->kp) + (i * pid->ki) + (d * pid->kd)) > pid->limit)) || + if ((pid->limit > SIGMA && (fabsf((error * pid->kp) + (i * pid->ki) + (d * pid->kd)) > pid->limit)) || fabsf(i) > pid->intmax) { i = pid->integral; // If saturated then do not update integral value pid->saturated = 1; @@ -186,7 +188,7 @@ __EXPORT float pid_calculate(PID_t *pid, float sp, float val, float val_dot, flo float output = (error * pid->kp) + (i * pid->ki) + (d * pid->kd); if (isfinite(output)) { - if (pid->limit != 0.0f) { + if (pid->limit > SIGMA) { if (output > pid->limit) { output = pid->limit; -- cgit v1.2.3