Fixed throttle scaling issue, harmonized FMU and IO RC scaling code

This commit is contained in:
Lorenz Meier
2013-03-07 11:45:23 +01:00
parent c993ba5bbc
commit ff5ca82c75
2 changed files with 32 additions and 17 deletions
+28 -14
View File
@@ -1125,31 +1125,45 @@ Sensors::ppm_poll()
/* Read out values from raw message */
for (unsigned int i = 0; i < channel_limit; i++) {
/* scale around the mid point differently for lower and upper range */
/*
* 1) Constrain to min/max values, as later processing depends on bounds.
*/
if (rc_input.values[i] < _parameters.min[i])
rc_input.values[i] = _parameters.min[i];
if (rc_input.values[i] > _parameters.max[i])
rc_input.values[i] = _parameters.max[i];
/*
* 2) Scale around the mid point differently for lower and upper range.
*
* This is necessary as they don't share the same endpoints and slope.
*
* First normalize to 0..1 range with correct sign (below or above center),
* the total range is 2 (-1..1).
* If center (trim) == min, scale to 0..1, if center (trim) == max,
* scale to -1..0.
*
* As the min and max bounds were enforced in step 1), division by zero
* cannot occur, as for the case of center == min or center == max the if
* statement is mutually exclusive with the arithmetic NaN case.
*
* DO NOT REMOVE OR ALTER STEP 1!
*/
if (rc_input.values[i] > (_parameters.trim[i] + _parameters.dz[i])) {
_rc.chan[i].scaled = (rc_input.values[i] - _parameters.trim[i]) / (float)(_parameters.max[i] - _parameters.trim[i]);
_rc.chan[i].scaled = (rc_input.values[i] - _parameters.trim[i] - _parameters.dz[i]) / (float)(_parameters.max[i] - _parameters.trim[i] - _parameters.dz[i]);
} else if (rc_input.values[i] < (_parameters.trim[i] - _parameters.dz[i])) {
/* division by zero impossible for trim == min (as for throttle), as this falls in the above if clause */
_rc.chan[i].scaled = -((_parameters.trim[i] - rc_input.values[i]) / (float)(_parameters.trim[i] - _parameters.min[i]));
_rc.chan[i].scaled = (rc_input.values[i] - _parameters.trim[i] - _parameters.dz[i]) / (float)(_parameters.trim[i] - _parameters.min[i] - _parameters.dz[i]);
} else {
/* in the configured dead zone, output zero */
_rc.chan[i].scaled = 0.0f;
}
/* reverse channel if required */
if (i == (int)_rc.function[THROTTLE]) {
if ((int)_parameters.rev[i] == -1) {
_rc.chan[i].scaled = 1.0f + -1.0f * _rc.chan[i].scaled;
}
} else {
_rc.chan[i].scaled *= _parameters.rev[i];
}
_rc.chan[i].scaled *= _parameters.rev[i];
/* handle any parameter-induced blowups */
if (isnan(_rc.chan[i].scaled) || isinf(_rc.chan[i].scaled))
if (!isfinite(_rc.chan[i].scaled))
_rc.chan[i].scaled = 0.0f;
}