PX4-Autopilot/src/lib/pid/PIDTest.cpp
2024-11-26 16:13:48 +01:00

130 lines
4.7 KiB
C++

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#include <gtest/gtest.h>
#include <PID.hpp>
TEST(PIDTest, AllZeroCase)
{
PID pid;
EXPECT_FLOAT_EQ(pid.update(0.f, 0.f, false), 0.f);
}
TEST(PIDTest, OutputLimit)
{
PID pid;
pid.setOutputLimit(.01f);
pid.setGains(.1f, 0.f, 0.f);
pid.setSetpoint(1.f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.f, false), .01f);
EXPECT_FLOAT_EQ(pid.update(.9f, 0.f, false), .01f);
EXPECT_NEAR(pid.update(.95f, 0.f, false), .005f, 1e-6f);
EXPECT_FLOAT_EQ(pid.update(1.f, 0.f, false), 0.f);
EXPECT_NEAR(pid.update(1.05f, 0.f, false), -.005f, 1e-6f);
EXPECT_FLOAT_EQ(pid.update(1.1f, 0.f, false), -.01f);
EXPECT_FLOAT_EQ(pid.update(1.15f, 0.f, false), -.01f);
EXPECT_FLOAT_EQ(pid.update(2.f, 0.f, false), -.01f);
}
TEST(PIDTest, ProportinalOnly)
{
PID pid;
pid.setOutputLimit(1.f);
pid.setGains(.1f, 0.f, 0.f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.f, false), 0.f);
pid.setSetpoint(1.f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.f, false), .1f);
EXPECT_FLOAT_EQ(pid.update(1.f, 0.f, false), 0.f);
float plant = 0.f;
float output = 10000.f;
int i; // need function scope to check how many steps
for (i = 1000; i > 0; i--) {
const float output_new = pid.update(plant, 0.f, false);
plant += output_new;
// expect the output to get smaller with each iteration
if (output_new >= output) {
break;
}
output = output_new;
}
EXPECT_FLOAT_EQ(plant, 1.f);
EXPECT_GT(i, 0); // it shouldn't have taken longer than an iteration timeout to converge
}
TEST(PIDTest, InteralOpenLoop)
{
PID pid;
pid.setOutputLimit(1.f);
pid.setGains(0.f, .1f, 0.f);
pid.setIntegralLimit(.05f);
pid.setSetpoint(1.f);
// Zero error
EXPECT_FLOAT_EQ(pid.update(1.f, 0.f, true), 0.f);
EXPECT_FLOAT_EQ(pid.update(1.f, 0.f, true), 0.f);
EXPECT_FLOAT_EQ(pid.update(1.f, 0.f, true), 0.f);
// Open loop ramp up
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), 0.f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .01f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .02f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .03f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .04f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .05f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .05f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .05f);
// Open loop ramp down
pid.setSetpoint(-1.f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .05f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .04f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .03f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), .02f);
EXPECT_NEAR(pid.update(0.f, 0.1f, true), .01f, 1e-6f);
EXPECT_NEAR(pid.update(0.f, 0.1f, true), 0.f, 1e-6f);
EXPECT_NEAR(pid.update(0.f, 0.1f, true), -.01f, 1e-6f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.02f);
EXPECT_NEAR(pid.update(0.f, 0.1f, true), -.03f, 1e-6f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.04f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.05f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.05f);
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.05f);
pid.resetIntegral();
EXPECT_FLOAT_EQ(pid.update(0.f, 0.1f, true), -.01f);
}