Moved Drivetrain from y2017 python to frc971
Change-Id: If931cf988d2615acc286d288fc0e5c9e7e3a5b90
diff --git a/y2017/control_loops/python/polydrivetrain.py b/y2017/control_loops/python/polydrivetrain.py
index d3a5683..701308e 100755
--- a/y2017/control_loops/python/polydrivetrain.py
+++ b/y2017/control_loops/python/polydrivetrain.py
@@ -1,13 +1,8 @@
#!/usr/bin/python
-import numpy
import sys
-from frc971.control_loops.python import polytope
from y2017.control_loops.python import drivetrain
-from frc971.control_loops.python import control_loop
-from frc971.control_loops.python import controls
-from frc971.control_loops.python.cim import CIM
-from matplotlib import pylab
+from frc971.control_loops.python import polydrivetrain
import gflags
import glog
@@ -21,479 +16,14 @@
except gflags.DuplicateFlagError:
pass
-def CoerceGoal(region, K, w, R):
- """Intersects a line with a region, and finds the closest point to R.
-
- Finds a point that is closest to R inside the region, and on the line
- defined by K X = w. If it is not possible to find a point on the line,
- finds a point that is inside the region and closest to the line. This
- function assumes that
-
- Args:
- region: HPolytope, the valid goal region.
- K: numpy.matrix (2 x 1), the matrix for the equation [K1, K2] [x1; x2] = w
- w: float, the offset in the equation above.
- R: numpy.matrix (2 x 1), the point to be closest to.
-
- Returns:
- numpy.matrix (2 x 1), the point.
- """
- return DoCoerceGoal(region, K, w, R)[0]
-
-def DoCoerceGoal(region, K, w, R):
- if region.IsInside(R):
- return (R, True)
-
- perpendicular_vector = K.T / numpy.linalg.norm(K)
- parallel_vector = numpy.matrix([[perpendicular_vector[1, 0]],
- [-perpendicular_vector[0, 0]]])
-
- # We want to impose the constraint K * X = w on the polytope H * X <= k.
- # We do this by breaking X up into parallel and perpendicular components to
- # the half plane. This gives us the following equation.
- #
- # parallel * (parallel.T \dot X) + perpendicular * (perpendicular \dot X)) = X
- #
- # Then, substitute this into the polytope.
- #
- # H * (parallel * (parallel.T \dot X) + perpendicular * (perpendicular \dot X)) <= k
- #
- # Substitute K * X = w
- #
- # H * parallel * (parallel.T \dot X) + H * perpendicular * w <= k
- #
- # Move all the knowns to the right side.
- #
- # H * parallel * ([parallel1 parallel2] * X) <= k - H * perpendicular * w
- #
- # Let t = parallel.T \dot X, the component parallel to the surface.
- #
- # H * parallel * t <= k - H * perpendicular * w
- #
- # This is a polytope which we can solve, and use to figure out the range of X
- # that we care about!
-
- t_poly = polytope.HPolytope(
- region.H * parallel_vector,
- region.k - region.H * perpendicular_vector * w)
-
- vertices = t_poly.Vertices()
-
- if vertices.shape[0]:
- # The region exists!
- # Find the closest vertex
- min_distance = numpy.infty
- closest_point = None
- for vertex in vertices:
- point = parallel_vector * vertex + perpendicular_vector * w
- length = numpy.linalg.norm(R - point)
- if length < min_distance:
- min_distance = length
- closest_point = point
-
- return (closest_point, True)
- else:
- # Find the vertex of the space that is closest to the line.
- region_vertices = region.Vertices()
- min_distance = numpy.infty
- closest_point = None
- for vertex in region_vertices:
- point = vertex.T
- length = numpy.abs((perpendicular_vector.T * point)[0, 0])
- if length < min_distance:
- min_distance = length
- closest_point = point
-
- return (closest_point, False)
-
-
-class VelocityDrivetrainModel(control_loop.ControlLoop):
- def __init__(self, left_low=True, right_low=True, name="VelocityDrivetrainModel"):
- super(VelocityDrivetrainModel, self).__init__(name)
- self._drivetrain = drivetrain.Drivetrain(left_low=left_low,
- right_low=right_low)
- self.dt = 0.00505
- self.A_continuous = numpy.matrix(
- [[self._drivetrain.A_continuous[1, 1], self._drivetrain.A_continuous[1, 3]],
- [self._drivetrain.A_continuous[3, 1], self._drivetrain.A_continuous[3, 3]]])
-
- self.B_continuous = numpy.matrix(
- [[self._drivetrain.B_continuous[1, 0], self._drivetrain.B_continuous[1, 1]],
- [self._drivetrain.B_continuous[3, 0], self._drivetrain.B_continuous[3, 1]]])
- self.C = numpy.matrix(numpy.eye(2))
- self.D = numpy.matrix(numpy.zeros((2, 2)))
-
- self.A, self.B = self.ContinuousToDiscrete(self.A_continuous,
- self.B_continuous, self.dt)
-
- # FF * X = U (steady state)
- self.FF = self.B.I * (numpy.eye(2) - self.A)
-
- self.PlaceControllerPoles([0.90, 0.90])
- self.PlaceObserverPoles([0.02, 0.02])
-
- self.G_high = self._drivetrain.G_high
- self.G_low = self._drivetrain.G_low
- self.resistance = self._drivetrain.resistance
- self.r = self._drivetrain.r
- self.Kv = self._drivetrain.Kv
- self.Kt = self._drivetrain.Kt
-
- self.U_max = self._drivetrain.U_max
- self.U_min = self._drivetrain.U_min
-
-
-class VelocityDrivetrain(object):
- HIGH = 'high'
- LOW = 'low'
- SHIFTING_UP = 'up'
- SHIFTING_DOWN = 'down'
-
- def __init__(self):
- self.drivetrain_low_low = VelocityDrivetrainModel(
- left_low=True, right_low=True, name='VelocityDrivetrainLowLow')
- self.drivetrain_low_high = VelocityDrivetrainModel(left_low=True, right_low=False, name='VelocityDrivetrainLowHigh')
- self.drivetrain_high_low = VelocityDrivetrainModel(left_low=False, right_low=True, name = 'VelocityDrivetrainHighLow')
- self.drivetrain_high_high = VelocityDrivetrainModel(left_low=False, right_low=False, name = 'VelocityDrivetrainHighHigh')
-
- # X is [lvel, rvel]
- self.X = numpy.matrix(
- [[0.0],
- [0.0]])
-
- self.U_poly = polytope.HPolytope(
- numpy.matrix([[1, 0],
- [-1, 0],
- [0, 1],
- [0, -1]]),
- numpy.matrix([[12],
- [12],
- [12],
- [12]]))
-
- self.U_max = numpy.matrix(
- [[12.0],
- [12.0]])
- self.U_min = numpy.matrix(
- [[-12.0000000000],
- [-12.0000000000]])
-
- self.dt = 0.00505
-
- self.R = numpy.matrix(
- [[0.0],
- [0.0]])
-
- self.U_ideal = numpy.matrix(
- [[0.0],
- [0.0]])
-
- # ttrust is the comprimise between having full throttle negative inertia,
- # and having no throttle negative inertia. A value of 0 is full throttle
- # inertia. A value of 1 is no throttle negative inertia.
- self.ttrust = 1.0
-
- self.left_gear = VelocityDrivetrain.LOW
- self.right_gear = VelocityDrivetrain.LOW
- self.left_shifter_position = 0.0
- self.right_shifter_position = 0.0
- self.left_cim = CIM()
- self.right_cim = CIM()
-
- def IsInGear(self, gear):
- return gear is VelocityDrivetrain.HIGH or gear is VelocityDrivetrain.LOW
-
- def MotorRPM(self, shifter_position, velocity):
- if shifter_position > 0.5:
- return (velocity / self.CurrentDrivetrain().G_high /
- self.CurrentDrivetrain().r)
- else:
- return (velocity / self.CurrentDrivetrain().G_low /
- self.CurrentDrivetrain().r)
-
- def CurrentDrivetrain(self):
- if self.left_shifter_position > 0.5:
- if self.right_shifter_position > 0.5:
- return self.drivetrain_high_high
- else:
- return self.drivetrain_high_low
- else:
- if self.right_shifter_position > 0.5:
- return self.drivetrain_low_high
- else:
- return self.drivetrain_low_low
-
- def SimShifter(self, gear, shifter_position):
- if gear is VelocityDrivetrain.HIGH or gear is VelocityDrivetrain.SHIFTING_UP:
- shifter_position = min(shifter_position + 0.5, 1.0)
- else:
- shifter_position = max(shifter_position - 0.5, 0.0)
-
- if shifter_position == 1.0:
- gear = VelocityDrivetrain.HIGH
- elif shifter_position == 0.0:
- gear = VelocityDrivetrain.LOW
-
- return gear, shifter_position
-
- def ComputeGear(self, wheel_velocity, should_print=False, current_gear=False, gear_name=None):
- high_omega = (wheel_velocity / self.CurrentDrivetrain().G_high /
- self.CurrentDrivetrain().r)
- low_omega = (wheel_velocity / self.CurrentDrivetrain().G_low /
- self.CurrentDrivetrain().r)
- #print gear_name, "Motor Energy Difference.", 0.5 * 0.000140032647 * (low_omega * low_omega - high_omega * high_omega), "joules"
- high_torque = ((12.0 - high_omega / self.CurrentDrivetrain().Kv) *
- self.CurrentDrivetrain().Kt / self.CurrentDrivetrain().resistance)
- low_torque = ((12.0 - low_omega / self.CurrentDrivetrain().Kv) *
- self.CurrentDrivetrain().Kt / self.CurrentDrivetrain().resistance)
- high_power = high_torque * high_omega
- low_power = low_torque * low_omega
- #if should_print:
- # print gear_name, "High omega", high_omega, "Low omega", low_omega
- # print gear_name, "High torque", high_torque, "Low torque", low_torque
- # print gear_name, "High power", high_power, "Low power", low_power
-
- # Shift algorithm improvements.
- # TODO(aschuh):
- # It takes time to shift. Shifting down for 1 cycle doesn't make sense
- # because you will end up slower than without shifting. Figure out how
- # to include that info.
- # If the driver is still in high gear, but isn't asking for the extra power
- # from low gear, don't shift until he asks for it.
- goal_gear_is_high = high_power > low_power
- #goal_gear_is_high = True
-
- if not self.IsInGear(current_gear):
- glog.debug('%s Not in gear.', gear_name)
- return current_gear
- else:
- is_high = current_gear is VelocityDrivetrain.HIGH
- if is_high != goal_gear_is_high:
- if goal_gear_is_high:
- glog.debug('%s Shifting up.', gear_name)
- return VelocityDrivetrain.SHIFTING_UP
- else:
- glog.debug('%s Shifting down.', gear_name)
- return VelocityDrivetrain.SHIFTING_DOWN
- else:
- return current_gear
-
- def FilterVelocity(self, throttle):
- # Invert the plant to figure out how the velocity filter would have to work
- # out in order to filter out the forwards negative inertia.
- # This math assumes that the left and right power and velocity are equal.
-
- # The throttle filter should filter such that the motor in the highest gear
- # should be controlling the time constant.
- # Do this by finding the index of FF that has the lowest value, and computing
- # the sums using that index.
- FF_sum = self.CurrentDrivetrain().FF.sum(axis=1)
- min_FF_sum_index = numpy.argmin(FF_sum)
- min_FF_sum = FF_sum[min_FF_sum_index, 0]
- min_K_sum = self.CurrentDrivetrain().K[min_FF_sum_index, :].sum()
- # Compute the FF sum for high gear.
- high_min_FF_sum = self.drivetrain_high_high.FF[0, :].sum()
-
- # U = self.K[0, :].sum() * (R - x_avg) + self.FF[0, :].sum() * R
- # throttle * 12.0 = (self.K[0, :].sum() + self.FF[0, :].sum()) * R
- # - self.K[0, :].sum() * x_avg
-
- # R = (throttle * 12.0 + self.K[0, :].sum() * x_avg) /
- # (self.K[0, :].sum() + self.FF[0, :].sum())
-
- # U = (K + FF) * R - K * X
- # (K + FF) ^-1 * (U + K * X) = R
-
- # Scale throttle by min_FF_sum / high_min_FF_sum. This will make low gear
- # have the same velocity goal as high gear, and so that the robot will hold
- # the same speed for the same throttle for all gears.
- adjusted_ff_voltage = numpy.clip(throttle * 12.0 * min_FF_sum / high_min_FF_sum, -12.0, 12.0)
- return ((adjusted_ff_voltage + self.ttrust * min_K_sum * (self.X[0, 0] + self.X[1, 0]) / 2.0)
- / (self.ttrust * min_K_sum + min_FF_sum))
-
- def Update(self, throttle, steering):
- # Shift into the gear which sends the most power to the floor.
- # This is the same as sending the most torque down to the floor at the
- # wheel.
-
- self.left_gear = self.right_gear = True
- if True:
- self.left_gear = self.ComputeGear(self.X[0, 0], should_print=True,
- current_gear=self.left_gear,
- gear_name="left")
- self.right_gear = self.ComputeGear(self.X[1, 0], should_print=True,
- current_gear=self.right_gear,
- gear_name="right")
- if self.IsInGear(self.left_gear):
- self.left_cim.X[0, 0] = self.MotorRPM(self.left_shifter_position, self.X[0, 0])
-
- if self.IsInGear(self.right_gear):
- self.right_cim.X[0, 0] = self.MotorRPM(self.right_shifter_position, self.X[0, 0])
-
- if self.IsInGear(self.left_gear) and self.IsInGear(self.right_gear):
- # Filter the throttle to provide a nicer response.
- fvel = self.FilterVelocity(throttle)
-
- # Constant radius means that angualar_velocity / linear_velocity = constant.
- # Compute the left and right velocities.
- steering_velocity = numpy.abs(fvel) * steering
- left_velocity = fvel - steering_velocity
- right_velocity = fvel + steering_velocity
-
- # Write this constraint in the form of K * R = w
- # angular velocity / linear velocity = constant
- # (left - right) / (left + right) = constant
- # left - right = constant * left + constant * right
-
- # (fvel - steering * numpy.abs(fvel) - fvel - steering * numpy.abs(fvel)) /
- # (fvel - steering * numpy.abs(fvel) + fvel + steering * numpy.abs(fvel)) =
- # constant
- # (- 2 * steering * numpy.abs(fvel)) / (2 * fvel) = constant
- # (-steering * sign(fvel)) = constant
- # (-steering * sign(fvel)) * (left + right) = left - right
- # (steering * sign(fvel) + 1) * left + (steering * sign(fvel) - 1) * right = 0
-
- equality_k = numpy.matrix(
- [[1 + steering * numpy.sign(fvel), -(1 - steering * numpy.sign(fvel))]])
- equality_w = 0.0
-
- self.R[0, 0] = left_velocity
- self.R[1, 0] = right_velocity
-
- # Construct a constraint on R by manipulating the constraint on U
- # Start out with H * U <= k
- # U = FF * R + K * (R - X)
- # H * (FF * R + K * R - K * X) <= k
- # H * (FF + K) * R <= k + H * K * X
- R_poly = polytope.HPolytope(
- self.U_poly.H * (self.CurrentDrivetrain().K + self.CurrentDrivetrain().FF),
- self.U_poly.k + self.U_poly.H * self.CurrentDrivetrain().K * self.X)
-
- # Limit R back inside the box.
- self.boxed_R = CoerceGoal(R_poly, equality_k, equality_w, self.R)
-
- FF_volts = self.CurrentDrivetrain().FF * self.boxed_R
- self.U_ideal = self.CurrentDrivetrain().K * (self.boxed_R - self.X) + FF_volts
- else:
- glog.debug('Not all in gear')
- if not self.IsInGear(self.left_gear) and not self.IsInGear(self.right_gear):
- # TODO(austin): Use battery volts here.
- R_left = self.MotorRPM(self.left_shifter_position, self.X[0, 0])
- self.U_ideal[0, 0] = numpy.clip(
- self.left_cim.K * (R_left - self.left_cim.X) + R_left / self.left_cim.Kv,
- self.left_cim.U_min, self.left_cim.U_max)
- self.left_cim.Update(self.U_ideal[0, 0])
-
- R_right = self.MotorRPM(self.right_shifter_position, self.X[1, 0])
- self.U_ideal[1, 0] = numpy.clip(
- self.right_cim.K * (R_right - self.right_cim.X) + R_right / self.right_cim.Kv,
- self.right_cim.U_min, self.right_cim.U_max)
- self.right_cim.Update(self.U_ideal[1, 0])
- else:
- assert False
-
- self.U = numpy.clip(self.U_ideal, self.U_min, self.U_max)
-
- # TODO(austin): Model the robot as not accelerating when you shift...
- # This hack only works when you shift at the same time.
- if self.IsInGear(self.left_gear) and self.IsInGear(self.right_gear):
- self.X = self.CurrentDrivetrain().A * self.X + self.CurrentDrivetrain().B * self.U
-
- self.left_gear, self.left_shifter_position = self.SimShifter(
- self.left_gear, self.left_shifter_position)
- self.right_gear, self.right_shifter_position = self.SimShifter(
- self.right_gear, self.right_shifter_position)
-
- glog.debug('U is %s %s', str(self.U[0, 0]), str(self.U[1, 0]))
- glog.debug('Left shifter %s %d Right shifter %s %d',
- self.left_gear, self.left_shifter_position,
- self.right_gear, self.right_shifter_position)
-
-
def main(argv):
- vdrivetrain = VelocityDrivetrain()
-
- if not FLAGS.plot:
- if len(argv) != 5:
- glog.fatal('Expected .h file name and .cc file name')
- else:
- namespaces = ['y2017', 'control_loops', 'drivetrain']
- dog_loop_writer = control_loop.ControlLoopWriter(
- "VelocityDrivetrain", [vdrivetrain.drivetrain_low_low,
- vdrivetrain.drivetrain_low_high,
- vdrivetrain.drivetrain_high_low,
- vdrivetrain.drivetrain_high_high],
- namespaces=namespaces)
-
- dog_loop_writer.Write(argv[1], argv[2])
-
- cim_writer = control_loop.ControlLoopWriter("CIM", [CIM()])
-
- cim_writer.Write(argv[3], argv[4])
- return
-
- vl_plot = []
- vr_plot = []
- ul_plot = []
- ur_plot = []
- radius_plot = []
- t_plot = []
- left_gear_plot = []
- right_gear_plot = []
- vdrivetrain.left_shifter_position = 0.0
- vdrivetrain.right_shifter_position = 0.0
- vdrivetrain.left_gear = VelocityDrivetrain.LOW
- vdrivetrain.right_gear = VelocityDrivetrain.LOW
-
- glog.debug('K is %s', str(vdrivetrain.CurrentDrivetrain().K))
-
- if vdrivetrain.left_gear is VelocityDrivetrain.HIGH:
- glog.debug('Left is high')
+ if FLAGS.plot:
+ polydrivetrain.PlotPolyDrivetrainMotions(drivetrain.kDrivetrain)
+ elif len(argv) != 5:
+ glog.fatal('Expected .h file name and .cc file name')
else:
- glog.debug('Left is low')
- if vdrivetrain.right_gear is VelocityDrivetrain.HIGH:
- glog.debug('Right is high')
- else:
- glog.debug('Right is low')
-
- for t in numpy.arange(0, 1.7, vdrivetrain.dt):
- if t < 0.5:
- vdrivetrain.Update(throttle=0.00, steering=1.0)
- elif t < 1.2:
- vdrivetrain.Update(throttle=0.5, steering=1.0)
- else:
- vdrivetrain.Update(throttle=0.00, steering=1.0)
- t_plot.append(t)
- vl_plot.append(vdrivetrain.X[0, 0])
- vr_plot.append(vdrivetrain.X[1, 0])
- ul_plot.append(vdrivetrain.U[0, 0])
- ur_plot.append(vdrivetrain.U[1, 0])
- left_gear_plot.append((vdrivetrain.left_gear is VelocityDrivetrain.HIGH) * 2.0 - 10.0)
- right_gear_plot.append((vdrivetrain.right_gear is VelocityDrivetrain.HIGH) * 2.0 - 10.0)
-
- fwd_velocity = (vdrivetrain.X[1, 0] + vdrivetrain.X[0, 0]) / 2
- turn_velocity = (vdrivetrain.X[1, 0] - vdrivetrain.X[0, 0])
- if abs(fwd_velocity) < 0.0000001:
- radius_plot.append(turn_velocity)
- else:
- radius_plot.append(turn_velocity / fwd_velocity)
-
- # TODO(austin):
- # Shifting compensation.
-
- # Tighten the turn.
- # Closed loop drive.
-
- pylab.plot(t_plot, vl_plot, label='left velocity')
- pylab.plot(t_plot, vr_plot, label='right velocity')
- pylab.plot(t_plot, ul_plot, label='left voltage')
- pylab.plot(t_plot, ur_plot, label='right voltage')
- pylab.plot(t_plot, radius_plot, label='radius')
- pylab.plot(t_plot, left_gear_plot, label='left gear high')
- pylab.plot(t_plot, right_gear_plot, label='right gear high')
- pylab.legend()
- pylab.show()
- return 0
+ polydrivetrain.WritePolyDrivetrain(argv[1:3], argv[3:5], 'y2017',
+ drivetrain.kDrivetrain)
if __name__ == '__main__':
argv = FLAGS(sys.argv)