add trapezoidal profile tests

Author: LucienMorey

subprojects/robotpy-wpimath/tests/trajectory/test_trapezoidal_profile.py

@@ -0,0 +1,182 @@
+# Copyright (c) FIRST and other WPILib contributors.
+# Open Source Software; you can modify and/or share it under the terms of
+# the WPILib BSD license file in the root directory of this project.
+
+
+import math
+
+from wpimath.trajectory import TrapezoidProfile
+
+kDt = 0.01  # 10 ms
+
+
+def expect_near_units(val1, val2, eps):
+    assert abs(val1 - val2) <= eps
+
+
+def expect_lt_or_near_units(val1, val2, eps):
+    if val1 <= val2:
+        assert val1 <= val2
+    else:
+        expect_near_units(val1, val2, eps)
+
+
+def test_reaches_goal():
+    constraints = TrapezoidProfile.Constraints(1.75, 0.75)
+    goal = TrapezoidProfile.State(3.0, 0.0)
+    state = TrapezoidProfile.State()
+
+    profile = TrapezoidProfile(constraints)
+    for _ in range(450):
+        state = profile.calculate(kDt, state, goal)
+    assert state == goal
+
+
+def test_pos_continuous_under_vel_change():
+    constraints = TrapezoidProfile.Constraints(1.75, 0.75)
+    goal = TrapezoidProfile.State(12.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+    state = profile.calculate(kDt, TrapezoidProfile.State(), goal)
+
+    last_pos = state.position
+    for i in range(1600):
+        if i == 400:
+            constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+            profile = TrapezoidProfile(constraints)
+
+        state = profile.calculate(kDt, state, goal)
+        estimated_vel = (state.position - last_pos) / kDt
+
+        if i >= 400:
+            expect_lt_or_near_units(estimated_vel, constraints.maxVelocity, 1e-4)
+            assert state.velocity <= constraints.maxVelocity
+
+        last_pos = state.position
+
+    assert state == goal
+
+
+def test_backwards():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(-2.0, 0.0)
+    state = TrapezoidProfile.State()
+    profile = TrapezoidProfile(constraints)
+
+    for _ in range(400):
+        state = profile.calculate(kDt, state, goal)
+    assert state == goal
+
+
+def test_switch_goal_in_middle():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(-2.0, 0.0)
+    state = TrapezoidProfile.State()
+    profile = TrapezoidProfile(constraints)
+
+    for _ in range(200):
+        state = profile.calculate(kDt, state, goal)
+    assert state != goal
+
+    goal = TrapezoidProfile.State(0.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+    for _ in range(550):
+        state = profile.calculate(kDt, state, goal)
+    assert state == goal
+
+
+def test_top_speed():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(4.0, 0.0)
+    state = TrapezoidProfile.State()
+    profile = TrapezoidProfile(constraints)
+
+    for _ in range(200):
+        state = profile.calculate(kDt, state, goal)
+    expect_near_units(constraints.maxVelocity, state.velocity, 1e-4)
+
+    profile = TrapezoidProfile(constraints)
+    for _ in range(2000):
+        state = profile.calculate(kDt, state, goal)
+    assert state == goal
+
+
+def test_timing_to_current():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(2.0, 0.0)
+    state = TrapezoidProfile.State()
+    profile = TrapezoidProfile(constraints)
+
+    for _ in range(400):
+        state = profile.calculate(kDt, state, goal)
+        expect_near_units(profile.timeLeftUntil(state.position), 0.0, 0.02)
+
+
+def test_timing_to_goal():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(2.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+
+    state = profile.calculate(kDt, goal, TrapezoidProfile.State())
+    predicted_time_left = profile.timeLeftUntil(goal.position)
+
+    reached_goal = False
+    for i in range(400):
+        state = profile.calculate(kDt, state, goal)
+        if not reached_goal and state == goal:
+            assert math.isclose(predicted_time_left, i * kDt, abs_tol=0.25)
+            reached_goal = True
+
+
+def test_timing_before_goal():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(2.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+
+    state = profile.calculate(kDt, goal, TrapezoidProfile.State())
+    predicted_time_left = profile.timeLeftUntil(1.0)
+
+    reached_goal = False
+    for i in range(400):
+        state = profile.calculate(kDt, state, goal)
+        if not reached_goal and abs(state.velocity - 1.0) < 1e-4:
+            assert math.isclose(predicted_time_left, i * kDt, abs_tol=0.02)
+            reached_goal = True
+
+
+def test_timing_to_negative_goal():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(-2.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+
+    state = profile.calculate(kDt, goal, TrapezoidProfile.State())
+    predicted_time_left = profile.timeLeftUntil(goal.position)
+
+    reached_goal = False
+    for i in range(400):
+        state = profile.calculate(kDt, state, goal)
+        if not reached_goal and state == goal:
+            assert math.isclose(predicted_time_left, i * kDt, abs_tol=0.25)
+            reached_goal = True
+
+
+def test_timing_before_negative_goal():
+    constraints = TrapezoidProfile.Constraints(0.75, 0.75)
+    goal = TrapezoidProfile.State(-2.0, 0.0)
+    profile = TrapezoidProfile(constraints)
+
+    state = profile.calculate(kDt, goal, TrapezoidProfile.State())
+    predicted_time_left = profile.timeLeftUntil(-1.0)
+
+    reached_goal = False
+    for i in range(400):
+        state = profile.calculate(kDt, state, goal)
+        if not reached_goal and abs(state.velocity + 1.0) < 1e-4:
+            assert math.isclose(predicted_time_left, i * kDt, abs_tol=0.02)
+            reached_goal = True
+
+
+def test_initialization_of_current_state():
+    constraints = TrapezoidProfile.Constraints(1.0, 1.0)
+    profile = TrapezoidProfile(constraints)
+    expect_near_units(profile.timeLeftUntil(0.0), 0.0, 1e-10)
+    expect_near_units(profile.totalTime(), 0.0, 1e-10)