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/**
* Copyright 2017 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "pidcontroller.hpp"
#include "ec/pid.hpp"
#include <algorithm>
#include <chrono>
#include <cmath>
#include <iostream>
#include <map>
#include <memory>
#include <thread>
#include <vector>
namespace pid_control
{
void PIDController::process(void)
{
double input;
double setpt;
double output;
// Get setpt value
setpt = setptProc();
// Get input value
input = inputProc();
auto info = getPIDInfo();
// if no hysteresis, maintain previous behavior
if (info->positiveHysteresis == 0 && info->negativeHysteresis == 0)
{
// Calculate new output
output = ec::pid(info, input, setpt);
// this variable isn't actually used in this context, but we're setting
// it here incase somebody uses it later it's the correct value
lastInput = input;
}
else
{
// initialize if not set yet
if (std::isnan(lastInput))
{
lastInput = input;
}
// if reading is outside of hysteresis bounds, use it for reading,
// otherwise use last reading without updating it first
else if ((input - lastInput) > info->positiveHysteresis)
{
lastInput = input;
}
else if ((lastInput - input) > info->negativeHysteresis)
{
lastInput = input;
}
output = ec::pid(info, lastInput, setpt);
}
// Output new value
outputProc(output);
return;
}
} // namespace pid_control