Tune drivetrain.

Add force knob, efficiency, IMU

Change-Id: I4fd12665490d4e535d5890c2edf8ae611938333d
diff --git a/frc971/control_loops/python/drivetrain.py b/frc971/control_loops/python/drivetrain.py
index 5665fd9..2380549 100644
--- a/frc971/control_loops/python/drivetrain.py
+++ b/frc971/control_loops/python/drivetrain.py
@@ -8,409 +8,530 @@
 import glog
 
 class DrivetrainParams(object):
-  def __init__(self, J, mass, robot_radius, wheel_radius, G_high, G_low,
-               q_pos_low, q_pos_high, q_vel_low, q_vel_high,
-               motor_type = control_loop.CIM(), num_motors = 2, dt = 0.00505,
-               controller_poles=[0.90, 0.90], observer_poles=[0.02, 0.02]):
-    """Defines all constants of a drivetrain.
+    def __init__(self,
+                 J,
+                 mass,
+                 robot_radius,
+                 wheel_radius,
+                 G_high,
+                 G_low,
+                 q_pos_low,
+                 q_pos_high,
+                 q_vel_low,
+                 q_vel_high,
+                 efficiency=0.60,
+                 has_imu=False,
+                 force=False,
+                 kf_q_voltage=10.0,
+                 motor_type=control_loop.CIM(),
+                 num_motors=2,
+                 dt=0.00505,
+                 controller_poles=[0.90, 0.90],
+                 observer_poles=[0.02, 0.02]):
+        """Defines all constants of a drivetrain.
 
-    Args:
-      J: float, Moment of inertia of drivetrain in kg m^2
-      mass: float, Mass of the robot in kg.
-      robot_radius: float, Radius of the robot, in meters (requires tuning by
-        hand).
-      wheel_radius: float, Radius of the wheels, in meters.
-      G_high: float, Gear ratio for high gear.
-      G_low: float, Gear ratio for low gear.
-      dt: float, Control loop time step.
-      q_pos_low: float, q position low gear.
-      q_pos_high: float, q position high gear.
-      q_vel_low: float, q velocity low gear.
-      q_vel_high: float, q velocity high gear.
-      motor_type: object, class of values defining the motor in drivetrain.
-      num_motors: int, number of motors on one side of drivetrain.
-      controller_poles: array, An array of poles. (See control_loop.py)
-      observer_poles: array, An array of poles. (See control_loop.py)
-    """
+        Args:
+          J: float, Moment of inertia of drivetrain in kg m^2
+          mass: float, Mass of the robot in kg.
+          robot_radius: float, Radius of the robot, in meters (requires tuning by
+            hand).
+          wheel_radius: float, Radius of the wheels, in meters.
+          G_high: float, Gear ratio for high gear.
+          G_low: float, Gear ratio for low gear.
+          dt: float, Control loop time step.
+          q_pos_low: float, q position low gear.
+          q_pos_high: float, q position high gear.
+          q_vel_low: float, q velocity low gear.
+          q_vel_high: float, q velocity high gear.
+          efficiency: float, gear box effiency.
+          has_imu: bool, true if imu is present.
+          force: bool, true if force.
+          kf_q_voltage: float
+          motor_type: object, class of values defining the motor in drivetrain.
+          num_motors: int, number of motors on one side of drivetrain.
+          controller_poles: array, An array of poles. (See control_loop.py)
+          observer_poles: array, An array of poles. (See control_loop.py)
+        """
 
-    self.J = J
-    self.mass = mass
-    self.robot_radius = robot_radius
-    self.wheel_radius = wheel_radius
-    self.G_high = G_high
-    self.G_low = G_low
-    self.dt = dt
-    self.q_pos_low = q_pos_low
-    self.q_pos_high = q_pos_high
-    self.q_vel_low = q_vel_low
-    self.q_vel_high = q_vel_high
-    self.motor_type = motor_type
-    self.num_motors = num_motors
-    self.controller_poles = controller_poles
-    self.observer_poles = observer_poles
+        self.J = J
+        self.mass = mass
+        self.robot_radius = robot_radius
+        self.wheel_radius = wheel_radius
+        self.G_high = G_high
+        self.G_low = G_low
+        self.dt = dt
+        self.q_pos_low = q_pos_low
+        self.q_pos_high = q_pos_high
+        self.q_vel_low = q_vel_low
+        self.q_vel_high = q_vel_high
+        self.efficiency = efficiency
+        self.has_imu = has_imu
+        self.kf_q_voltage = kf_q_voltage
+        self.motor_type = motor_type
+        self.force = force
+        self.num_motors = num_motors
+        self.controller_poles = controller_poles
+        self.observer_poles = observer_poles
+
 
 class Drivetrain(control_loop.ControlLoop):
-  def __init__(self, drivetrain_params, name="Drivetrain", left_low=True,
-               right_low=True):
-    """Defines a base drivetrain for a robot.
+    def __init__(self,
+                 drivetrain_params,
+                 name="Drivetrain",
+                 left_low=True,
+                 right_low=True):
+        """Defines a base drivetrain for a robot.
 
-    Args:
-      drivetrain_params: DrivetrainParams, class of values defining the drivetrain.
-      name: string, Name of this drivetrain.
-      left_low: bool, Whether the left is in high gear.
-      right_low: bool, Whether the right is in high gear.
-    """
-    super(Drivetrain, self).__init__(name)
+        Args:
+          drivetrain_params: DrivetrainParams, class of values defining the drivetrain.
+          name: string, Name of this drivetrain.
+          left_low: bool, Whether the left is in high gear.
+          right_low: bool, Whether the right is in high gear.
+        """
+        super(Drivetrain, self).__init__(name)
 
-    # Moment of inertia of the drivetrain in kg m^2
-    self.J = drivetrain_params.J
-    # Mass of the robot, in kg.
-    self.mass = drivetrain_params.mass
-    # Radius of the robot, in meters (requires tuning by hand)
-    self.robot_radius = drivetrain_params.robot_radius
-    # Radius of the wheels, in meters.
-    self.r = drivetrain_params.wheel_radius
+        # Moment of inertia of the drivetrain in kg m^2
+        self.J = drivetrain_params.J
+        # Mass of the robot, in kg.
+        self.mass = drivetrain_params.mass
+        # Radius of the robot, in meters (requires tuning by hand)
+        self.robot_radius = drivetrain_params.robot_radius
+        # Radius of the wheels, in meters.
+        self.r = drivetrain_params.wheel_radius
+        self.has_imu = drivetrain_params.has_imu
 
-    # Gear ratios
-    self.G_low = drivetrain_params.G_low
-    self.G_high = drivetrain_params.G_high
-    if left_low:
-      self.Gl = self.G_low
-    else:
-      self.Gl = self.G_high
-    if right_low:
-      self.Gr = self.G_low
-    else:
-      self.Gr = self.G_high
+        # Gear ratios
+        self.G_low = drivetrain_params.G_low
+        self.G_high = drivetrain_params.G_high
+        if left_low:
+            self.Gl = self.G_low
+        else:
+            self.Gl = self.G_high
+        if right_low:
+            self.Gr = self.G_low
+        else:
+            self.Gr = self.G_high
 
-    # Control loop time step
-    self.dt = drivetrain_params.dt
+        # Control loop time step
+        self.dt = drivetrain_params.dt
 
-    self.BuildDrivetrain(drivetrain_params.motor_type, drivetrain_params.num_motors);
+        self.efficiency = drivetrain_params.efficiency
+        self.force = drivetrain_params.force
 
-    if left_low or right_low:
-      q_pos = drivetrain_params.q_pos_low
-      q_vel = drivetrain_params.q_vel_low
-    else:
-      q_pos = drivetrain_params.q_pos_high
-      q_vel = drivetrain_params.q_vel_high
+        self.BuildDrivetrain(drivetrain_params.motor_type,
+                             drivetrain_params.num_motors)
 
-    self.BuildDrivetrainController(q_pos, q_vel)
+        if left_low or right_low:
+            q_pos = drivetrain_params.q_pos_low
+            q_vel = drivetrain_params.q_vel_low
+        else:
+            q_pos = drivetrain_params.q_pos_high
+            q_vel = drivetrain_params.q_vel_high
 
-    self.InitializeState()
+        self.BuildDrivetrainController(q_pos, q_vel)
 
-  def BuildDrivetrain(self, motor, num_motors_per_side):
-    self.motor = motor
-    # Number of motors per side
-    self.num_motors = num_motors_per_side
-    # Stall Torque in N m
-    self.stall_torque = motor.stall_torque * self.num_motors * 0.60
-    # Stall Current in Amps
-    self.stall_current = motor.stall_current * self.num_motors
-    # Free Speed in rad/s
-    self.free_speed = motor.free_speed
-    # Free Current in Amps
-    self.free_current = motor.free_current * self.num_motors
+        self.InitializeState()
 
-    # Effective motor resistance in ohms.
-    self.resistance = 12.0 / self.stall_current
+    def BuildDrivetrain(self, motor, num_motors_per_side):
+        self.motor = motor
+        # Number of motors per side
+        self.num_motors = num_motors_per_side
+        # Stall Torque in N m
+        self.stall_torque = motor.stall_torque * self.num_motors * self.efficiency
+        # Stall Current in Amps
+        self.stall_current = motor.stall_current * self.num_motors
+        # Free Speed in rad/s
+        self.free_speed = motor.free_speed
+        # Free Current in Amps
+        self.free_current = motor.free_current * self.num_motors
 
-    # Resistance of the motor, divided by the number of motors.
-    # Motor velocity constant
-    self.Kv = (self.free_speed / (12.0 - self.resistance * self.free_current))
-    # Torque constant
-    self.Kt = self.stall_torque / self.stall_current
+        # Effective motor resistance in ohms.
+        self.resistance = 12.0 / self.stall_current
 
-    # These describe the way that a given side of a robot will be influenced
-    # by the other side. Units of 1 / kg.
-    self.msp = 1.0 / self.mass + self.robot_radius * self.robot_radius / self.J
-    self.msn = 1.0 / self.mass - self.robot_radius * self.robot_radius / self.J
-    # The calculations which we will need for A and B.
-    self.tcl = self.Kt / self.Kv / (self.Gl * self.Gl * self.resistance * self.r * self.r)
-    self.tcr = self.Kt / self.Kv / (self.Gr * self.Gr * self.resistance * self.r * self.r)
-    self.mpl = self.Kt / (self.Gl * self.resistance * self.r)
-    self.mpr = self.Kt / (self.Gr * self.resistance * self.r)
+        # Resistance of the motor, divided by the number of motors.
+        # Motor velocity constant
+        self.Kv = (self.free_speed /
+                   (12.0 - self.resistance * self.free_current))
+        # Torque constant
+        self.Kt = self.stall_torque / self.stall_current
 
-    # State feedback matrices
-    # X will be of the format
-    # [[positionl], [velocityl], [positionr], velocityr]]
-    self.A_continuous = numpy.matrix(
-        [[0, 1, 0, 0],
-         [0, -self.msp * self.tcl, 0, -self.msn * self.tcr],
-         [0, 0, 0, 1],
-         [0, -self.msn * self.tcl, 0, -self.msp * self.tcr]])
-    self.B_continuous = numpy.matrix(
-        [[0, 0],
-         [self.msp * self.mpl, self.msn * self.mpr],
-         [0, 0],
-         [self.msn * self.mpl, self.msp * self.mpr]])
-    self.C = numpy.matrix([[1, 0, 0, 0],
-                           [0, 0, 1, 0]])
-    self.D = numpy.matrix([[0, 0],
-                           [0, 0]])
+        # These describe the way that a given side of a robot will be influenced
+        # by the other side. Units of 1 / kg.
+        self.msp = 1.0 / self.mass + self.robot_radius * self.robot_radius / self.J
+        self.msn = 1.0 / self.mass - self.robot_radius * self.robot_radius / self.J
+        # The calculations which we will need for A and B.
+        self.tcl = self.Kt / self.Kv / (
+            self.Gl * self.Gl * self.resistance * self.r * self.r)
+        self.tcr = self.Kt / self.Kv / (
+            self.Gr * self.Gr * self.resistance * self.r * self.r)
+        self.mpl = self.Kt / (self.Gl * self.resistance * self.r)
+        self.mpr = self.Kt / (self.Gr * self.resistance * self.r)
 
-    self.A, self.B = self.ContinuousToDiscrete(
-        self.A_continuous, self.B_continuous, self.dt)
+        # State feedback matrices
+        # X will be of the format
+        # [[positionl], [velocityl], [positionr], velocityr]]
+        self.A_continuous = numpy.matrix(
+            [[0, 1, 0, 0], [0, -self.msp * self.tcl, 0, -self.msn * self.tcr],
+             [0, 0, 0, 1], [0, -self.msn * self.tcl, 0, -self.msp * self.tcr]])
+        self.B_continuous = numpy.matrix(
+            [[0, 0], [self.msp * self.mpl, self.msn * self.mpr], [0, 0],
+             [self.msn * self.mpl, self.msp * self.mpr]])
+        self.C = numpy.matrix([[1, 0, 0, 0], [0, 0, 1, 0]])
+        self.D = numpy.matrix([[0, 0], [0, 0]])
 
-  def BuildDrivetrainController(self, q_pos, q_vel):
-    # Tune the LQR controller
-    self.Q = numpy.matrix([[(1.0 / (q_pos ** 2.0)), 0.0, 0.0, 0.0],
-                           [0.0, (1.0 / (q_vel ** 2.0)), 0.0, 0.0],
-                           [0.0, 0.0, (1.0 / (q_pos ** 2.0)), 0.0],
-                           [0.0, 0.0, 0.0, (1.0 / (q_vel ** 2.0))]])
+        self.A, self.B = self.ContinuousToDiscrete(self.A_continuous,
+                                                   self.B_continuous, self.dt)
 
-    self.R = numpy.matrix([[(1.0 / (12.0 ** 2.0)), 0.0],
-                           [0.0, (1.0 / (12.0 ** 2.0))]])
-    self.K = controls.dlqr(self.A, self.B, self.Q, self.R)
+    def BuildDrivetrainController(self, q_pos, q_vel):
+        # Tune the LQR controller
+        self.Q = numpy.matrix([[(1.0 / (q_pos**2.0)), 0.0, 0.0,
+                                0.0], [0.0, (1.0 / (q_vel**2.0)), 0.0, 0.0],
+                               [0.0, 0.0, (1.0 / (q_pos**2.0)),
+                                0.0], [0.0, 0.0, 0.0, (1.0 / (q_vel**2.0))]])
 
-    glog.debug('DT q_pos %f q_vel %s %s', q_pos, q_vel, self._name)
-    glog.debug(str(numpy.linalg.eig(self.A - self.B * self.K)[0]))
-    glog.debug('K %s', repr(self.K))
+        self.R = numpy.matrix([[(1.0 / (12.0**2.0)), 0.0],
+                               [0.0, (1.0 / (12.0**2.0))]])
+        self.K = controls.dlqr(self.A, self.B, self.Q, self.R)
 
-    self.hlp = 0.3
-    self.llp = 0.4
-    self.PlaceObserverPoles([self.hlp, self.hlp, self.llp, self.llp])
+        glog.debug('DT q_pos %f q_vel %s %s', q_pos, q_vel, self._name)
+        glog.debug(str(numpy.linalg.eig(self.A - self.B * self.K)[0]))
+        glog.debug('K %s', repr(self.K))
 
-    self.U_max = numpy.matrix([[12.0], [12.0]])
-    self.U_min = numpy.matrix([[-12.0], [-12.0]])
+        self.hlp = 0.3
+        self.llp = 0.4
+        self.PlaceObserverPoles([self.hlp, self.hlp, self.llp, self.llp])
+
+        self.U_max = numpy.matrix([[12.0], [12.0]])
+        self.U_min = numpy.matrix([[-12.0], [-12.0]])
+
 
 class KFDrivetrain(Drivetrain):
-  def __init__(self, drivetrain_params, name="KFDrivetrain",
-               left_low=True, right_low=True):
-    """Kalman filter values of a drivetrain.
+    def __init__(self,
+                 drivetrain_params,
+                 name="KFDrivetrain",
+                 left_low=True,
+                 right_low=True):
+        """Kalman filter values of a drivetrain.
 
-    Args:
-      drivetrain_params: DrivetrainParams, class of values defining the drivetrain.
-      name: string, Name of this drivetrain.
-      left_low: bool, Whether the left is in high gear.
-      right_low: bool, Whether the right is in high gear.
-    """
-    super(KFDrivetrain, self).__init__(drivetrain_params, name, left_low, right_low)
+        Args:
+          drivetrain_params: DrivetrainParams, class of values defining the drivetrain.
+          name: string, Name of this drivetrain.
+          left_low: bool, Whether the left is in high gear.
+          right_low: bool, Whether the right is in high gear.
+        """
+        super(KFDrivetrain, self).__init__(drivetrain_params, name, left_low,
+                                           right_low)
 
-    self.unaugmented_A_continuous = self.A_continuous
-    self.unaugmented_B_continuous = self.B_continuous
+        self.unaugmented_A_continuous = self.A_continuous
+        self.unaugmented_B_continuous = self.B_continuous
 
-    # The practical voltage applied to the wheels is
-    #   V_left = U_left + left_voltage_error
-    #
-    # The states are
-    # [left position, left velocity, right position, right velocity,
-    #  left voltage error, right voltage error, angular_error]
-    #
-    # The left and right positions are filtered encoder positions and are not
-    # adjusted for heading error.
-    # The turn velocity as computed by the left and right velocities is
-    # adjusted by the gyro velocity.
-    # The angular_error is the angular velocity error between the wheel speed
-    # and the gyro speed.
-    self.A_continuous = numpy.matrix(numpy.zeros((7, 7)))
-    self.B_continuous = numpy.matrix(numpy.zeros((7, 2)))
-    self.A_continuous[0:4,0:4] = self.unaugmented_A_continuous
-    self.A_continuous[0:4,4:6] = self.unaugmented_B_continuous
-    self.B_continuous[0:4,0:2] = self.unaugmented_B_continuous
-    self.A_continuous[0,6] = 1
-    self.A_continuous[2,6] = -1
+        # The practical voltage applied to the wheels is
+        #   V_left = U_left + left_voltage_error
+        #
+        # The states are
+        # [left position, left velocity, right position, right velocity,
+        #  left voltage error, right voltage error, angular_error]
+        #
+        # The left and right positions are filtered encoder positions and are not
+        # adjusted for heading error.
+        # The turn velocity as computed by the left and right velocities is
+        # adjusted by the gyro velocity.
+        # The angular_error is the angular velocity error between the wheel speed
+        # and the gyro speed.
+        self.A_continuous = numpy.matrix(numpy.zeros((7, 7)))
+        self.B_continuous = numpy.matrix(numpy.zeros((7, 2)))
+        self.A_continuous[0:4, 0:4] = self.unaugmented_A_continuous
 
-    self.A, self.B = self.ContinuousToDiscrete(
-        self.A_continuous, self.B_continuous, self.dt)
+        if self.force:
+            self.A_continuous[0:4, 4:6] = numpy.matrix(
+                [[0.0, 0.0], [self.msp, self.msn], [0.0, 0.0],
+                 [self.msn, self.msp]])
+            q_voltage = drivetrain_params.kf_q_voltage * self.mpl
+        else:
+            self.A_continuous[0:4, 4:6] = self.unaugmented_B_continuous
+            q_voltage = drivetrain_params.kf_q_voltage
 
-    self.C = numpy.matrix([[1, 0, 0, 0, 0, 0, 0],
-                           [0, 0, 1, 0, 0, 0, 0],
-                           [0, -0.5 / drivetrain_params.robot_radius, 0, 0.5 / drivetrain_params.robot_radius, 0, 0, 0]])
+        self.B_continuous[0:4, 0:2] = self.unaugmented_B_continuous
+        self.A_continuous[0, 6] = 1
+        self.A_continuous[2, 6] = -1
 
-    self.D = numpy.matrix([[0, 0],
-                           [0, 0],
-                           [0, 0]])
+        self.A, self.B = self.ContinuousToDiscrete(self.A_continuous,
+                                                   self.B_continuous, self.dt)
 
-    q_pos = 0.05
-    q_vel = 1.00
-    q_voltage = 10.0
-    q_encoder_uncertainty = 2.00
+        if self.has_imu:
+            self.C = numpy.matrix(
+                [[1, 0, 0, 0, 0, 0, 0], [0, 0, 1, 0, 0, 0, 0], [
+                    0, -0.5 / drivetrain_params.robot_radius, 0,
+                    0.5 / drivetrain_params.robot_radius, 0, 0, 0
+                ], [0, 0, 0, 0, 0, 0, 0]])
+            gravity = 9.8
+            self.C[3, 0:6] = 0.5 * (
+                self.A_continuous[1, 0:6] + self.A_continuous[3, 0:6]
+            ) / gravity
 
-    self.Q = numpy.matrix([[(q_pos ** 2.0), 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
-                           [0.0, (q_vel ** 2.0), 0.0, 0.0, 0.0, 0.0, 0.0],
-                           [0.0, 0.0, (q_pos ** 2.0), 0.0, 0.0, 0.0, 0.0],
-                           [0.0, 0.0, 0.0, (q_vel ** 2.0), 0.0, 0.0, 0.0],
-                           [0.0, 0.0, 0.0, 0.0, (q_voltage ** 2.0), 0.0, 0.0],
-                           [0.0, 0.0, 0.0, 0.0, 0.0, (q_voltage ** 2.0), 0.0],
-                           [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, (q_encoder_uncertainty ** 2.0)]])
+            self.D = numpy.matrix([[0, 0], [0, 0], [0, 0], [
+                0.5 *
+                (self.B_continuous[1, 0] + self.B_continuous[3, 0]) / gravity,
+                0.5 *
+                (self.B_continuous[1, 1] + self.B_continuous[3, 1]) / gravity
+            ]])
+        else:
+            self.C = numpy.matrix(
+                [[1, 0, 0, 0, 0, 0, 0], [0, 0, 1, 0, 0, 0, 0], [
+                    0, -0.5 / drivetrain_params.robot_radius, 0,
+                    0.5 / drivetrain_params.robot_radius, 0, 0, 0
+                ]])
 
-    r_pos =  0.0001
-    r_gyro = 0.000001
-    self.R = numpy.matrix([[(r_pos ** 2.0), 0.0, 0.0],
-                           [0.0, (r_pos ** 2.0), 0.0],
-                           [0.0, 0.0, (r_gyro ** 2.0)]])
+            self.D = numpy.matrix([[0, 0], [0, 0], [0, 0]])
 
-    # Solving for kf gains.
-    self.KalmanGain, self.Q_steady = controls.kalman(
-        A=self.A, B=self.B, C=self.C, Q=self.Q, R=self.R)
+        q_pos = 0.05
+        q_vel = 1.00
+        q_encoder_uncertainty = 2.00
 
-    self.L = self.A * self.KalmanGain
+        self.Q = numpy.matrix(
+            [[(q_pos**2.0), 0.0, 0.0, 0.0, 0.0, 0.0,
+              0.0], [0.0, (q_vel**2.0), 0.0, 0.0, 0.0, 0.0,
+                     0.0], [0.0, 0.0, (q_pos**2.0), 0.0, 0.0, 0.0,
+                            0.0], [0.0, 0.0, 0.0, (q_vel**2.0), 0.0, 0.0, 0.0],
+             [0.0, 0.0, 0.0, 0.0, (q_voltage**2.0), 0.0,
+              0.0], [0.0, 0.0, 0.0, 0.0, 0.0, (q_voltage**2.0), 0.0],
+             [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, (q_encoder_uncertainty**2.0)]])
 
-    unaug_K = self.K
+        r_pos = 0.0001
+        r_gyro = 0.000001
+        if self.has_imu:
+            r_accelerometer = 7.0
+            self.R = numpy.matrix([[(r_pos**2.0), 0.0, 0.0, 0.0],
+                                   [0.0, (r_pos**2.0), 0.0, 0.0],
+                                   [0.0, 0.0, (r_gyro**2.0), 0.0],
+                                   [0.0, 0.0, 0.0, (r_accelerometer**2.0)]])
+        else:
+            self.R = numpy.matrix([[(r_pos**2.0), 0.0, 0.0],
+                                   [0.0, (r_pos**2.0), 0.0],
+                                   [0.0, 0.0, (r_gyro**2.0)]])
 
-    # Implement a nice closed loop controller for use by the closed loop
-    # controller.
-    self.K = numpy.matrix(numpy.zeros((self.B.shape[1], self.A.shape[0])))
-    self.K[0:2, 0:4] = unaug_K
-    self.K[0, 4] = 1.0
-    self.K[1, 5] = 1.0
+        # Solving for kf gains.
+        self.KalmanGain, self.Q_steady = controls.kalman(
+            A=self.A, B=self.B, C=self.C, Q=self.Q, R=self.R)
 
-    self.Qff = numpy.matrix(numpy.zeros((4, 4)))
-    qff_pos = 0.005
-    qff_vel = 1.00
-    self.Qff[0, 0] = 1.0 / qff_pos ** 2.0
-    self.Qff[1, 1] = 1.0 / qff_vel ** 2.0
-    self.Qff[2, 2] = 1.0 / qff_pos ** 2.0
-    self.Qff[3, 3] = 1.0 / qff_vel ** 2.0
-    self.Kff = numpy.matrix(numpy.zeros((2, 7)))
-    self.Kff[0:2, 0:4] = controls.TwoStateFeedForwards(self.B[0:4,:], self.Qff)
+        if not self.has_imu:
+          self.KalmanGain = numpy.hstack((self.KalmanGain, numpy.matrix(numpy.zeros((7, 1)))))
+          self.C = numpy.vstack((self.C, numpy.matrix(numpy.zeros((1, 7)))))
+          self.D = numpy.vstack((self.D, numpy.matrix(numpy.zeros((1, 2)))))
 
-    self.InitializeState()
+        self.L = self.A * self.KalmanGain
+
+        unaug_K = self.K
+
+        # Implement a nice closed loop controller for use by the closed loop
+        # controller.
+        self.K = numpy.matrix(numpy.zeros((self.B.shape[1], self.A.shape[0])))
+        self.K[0:2, 0:4] = unaug_K
+        if self.force:
+            self.K[0, 4] = 1.0 / self.mpl
+            self.K[1, 5] = 1.0 / self.mpr
+        else:
+            self.K[0, 4] = 1.0
+            self.K[1, 5] = 1.0
+
+        self.Qff = numpy.matrix(numpy.zeros((4, 4)))
+        qff_pos = 0.005
+        qff_vel = 1.00
+        self.Qff[0, 0] = 1.0 / qff_pos**2.0
+        self.Qff[1, 1] = 1.0 / qff_vel**2.0
+        self.Qff[2, 2] = 1.0 / qff_pos**2.0
+        self.Qff[3, 3] = 1.0 / qff_vel**2.0
+        self.Kff = numpy.matrix(numpy.zeros((2, 7)))
+        self.Kff[0:2, 0:4] = controls.TwoStateFeedForwards(
+            self.B[0:4, :], self.Qff)
+
+        self.InitializeState()
 
 
 def WriteDrivetrain(drivetrain_files, kf_drivetrain_files, year_namespace,
                     drivetrain_params):
 
-  # Write the generated constants out to a file.
-  drivetrain_low_low = Drivetrain(name="DrivetrainLowLow",
-          left_low=True, right_low=True, drivetrain_params=drivetrain_params)
-  drivetrain_low_high = Drivetrain(name="DrivetrainLowHigh",
-          left_low=True, right_low=False, drivetrain_params=drivetrain_params)
-  drivetrain_high_low = Drivetrain(name="DrivetrainHighLow",
-          left_low=False, right_low=True, drivetrain_params=drivetrain_params)
-  drivetrain_high_high = Drivetrain(name="DrivetrainHighHigh",
-          left_low=False, right_low=False, drivetrain_params=drivetrain_params)
+    # Write the generated constants out to a file.
+    drivetrain_low_low = Drivetrain(
+        name="DrivetrainLowLow",
+        left_low=True,
+        right_low=True,
+        drivetrain_params=drivetrain_params)
+    drivetrain_low_high = Drivetrain(
+        name="DrivetrainLowHigh",
+        left_low=True,
+        right_low=False,
+        drivetrain_params=drivetrain_params)
+    drivetrain_high_low = Drivetrain(
+        name="DrivetrainHighLow",
+        left_low=False,
+        right_low=True,
+        drivetrain_params=drivetrain_params)
+    drivetrain_high_high = Drivetrain(
+        name="DrivetrainHighHigh",
+        left_low=False,
+        right_low=False,
+        drivetrain_params=drivetrain_params)
 
-  kf_drivetrain_low_low = KFDrivetrain(name="KFDrivetrainLowLow",
-          left_low=True, right_low=True, drivetrain_params=drivetrain_params)
-  kf_drivetrain_low_high = KFDrivetrain(name="KFDrivetrainLowHigh",
-          left_low=True, right_low=False, drivetrain_params=drivetrain_params)
-  kf_drivetrain_high_low = KFDrivetrain(name="KFDrivetrainHighLow",
-          left_low=False, right_low=True, drivetrain_params=drivetrain_params)
-  kf_drivetrain_high_high = KFDrivetrain(name="KFDrivetrainHighHigh",
-          left_low=False, right_low=False, drivetrain_params=drivetrain_params)
+    kf_drivetrain_low_low = KFDrivetrain(
+        name="KFDrivetrainLowLow",
+        left_low=True,
+        right_low=True,
+        drivetrain_params=drivetrain_params)
+    kf_drivetrain_low_high = KFDrivetrain(
+        name="KFDrivetrainLowHigh",
+        left_low=True,
+        right_low=False,
+        drivetrain_params=drivetrain_params)
+    kf_drivetrain_high_low = KFDrivetrain(
+        name="KFDrivetrainHighLow",
+        left_low=False,
+        right_low=True,
+        drivetrain_params=drivetrain_params)
+    kf_drivetrain_high_high = KFDrivetrain(
+        name="KFDrivetrainHighHigh",
+        left_low=False,
+        right_low=False,
+        drivetrain_params=drivetrain_params)
 
-  namespaces = [year_namespace, 'control_loops', 'drivetrain']
-  dog_loop_writer = control_loop.ControlLoopWriter(
-      "Drivetrain", [drivetrain_low_low, drivetrain_low_high,
-                     drivetrain_high_low, drivetrain_high_high],
-      namespaces = namespaces)
-  dog_loop_writer.AddConstant(control_loop.Constant("kDt", "%f",
-        drivetrain_low_low.dt))
-  dog_loop_writer.AddConstant(control_loop.Constant("kStallTorque", "%f",
-        drivetrain_low_low.stall_torque))
-  dog_loop_writer.AddConstant(control_loop.Constant("kStallCurrent", "%f",
-        drivetrain_low_low.stall_current))
-  dog_loop_writer.AddConstant(control_loop.Constant("kFreeSpeed", "%f",
-        drivetrain_low_low.free_speed))
-  dog_loop_writer.AddConstant(control_loop.Constant("kFreeCurrent", "%f",
-        drivetrain_low_low.free_current))
-  dog_loop_writer.AddConstant(control_loop.Constant("kJ", "%f",
-        drivetrain_low_low.J))
-  dog_loop_writer.AddConstant(control_loop.Constant("kMass", "%f",
-        drivetrain_low_low.mass))
-  dog_loop_writer.AddConstant(control_loop.Constant("kRobotRadius", "%f",
-        drivetrain_low_low.robot_radius))
-  dog_loop_writer.AddConstant(control_loop.Constant("kWheelRadius", "%f",
-        drivetrain_low_low.r))
-  dog_loop_writer.AddConstant(control_loop.Constant("kR", "%f",
-        drivetrain_low_low.resistance))
-  dog_loop_writer.AddConstant(control_loop.Constant("kV", "%f",
-        drivetrain_low_low.Kv))
-  dog_loop_writer.AddConstant(control_loop.Constant("kT", "%f",
-        drivetrain_low_low.Kt))
-  dog_loop_writer.AddConstant(control_loop.Constant("kLowGearRatio", "%f",
-        drivetrain_low_low.G_low))
-  dog_loop_writer.AddConstant(control_loop.Constant("kHighGearRatio", "%f",
-        drivetrain_high_high.G_high))
-  dog_loop_writer.AddConstant(control_loop.Constant("kHighOutputRatio", "%f",
-        drivetrain_high_high.G_high * drivetrain_high_high.r))
+    namespaces = [year_namespace, 'control_loops', 'drivetrain']
+    dog_loop_writer = control_loop.ControlLoopWriter(
+        "Drivetrain", [
+            drivetrain_low_low, drivetrain_low_high, drivetrain_high_low,
+            drivetrain_high_high
+        ],
+        namespaces=namespaces)
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kDt", "%f", drivetrain_low_low.dt))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kStallTorque", "%f",
+                              drivetrain_low_low.stall_torque))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kStallCurrent", "%f",
+                              drivetrain_low_low.stall_current))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kFreeSpeed", "%f",
+                              drivetrain_low_low.free_speed))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kFreeCurrent", "%f",
+                              drivetrain_low_low.free_current))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kJ", "%f", drivetrain_low_low.J))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kMass", "%f", drivetrain_low_low.mass))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kRobotRadius", "%f",
+                              drivetrain_low_low.robot_radius))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kWheelRadius", "%f", drivetrain_low_low.r))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kR", "%f", drivetrain_low_low.resistance))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kV", "%f", drivetrain_low_low.Kv))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kT", "%f", drivetrain_low_low.Kt))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kLowGearRatio", "%f", drivetrain_low_low.G_low))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant("kHighGearRatio", "%f",
+                              drivetrain_high_high.G_high))
+    dog_loop_writer.AddConstant(
+        control_loop.Constant(
+            "kHighOutputRatio", "%f",
+            drivetrain_high_high.G_high * drivetrain_high_high.r))
 
-  dog_loop_writer.Write(drivetrain_files[0], drivetrain_files[1])
+    dog_loop_writer.Write(drivetrain_files[0], drivetrain_files[1])
 
-  kf_loop_writer = control_loop.ControlLoopWriter(
-      "KFDrivetrain", [kf_drivetrain_low_low, kf_drivetrain_low_high,
-                       kf_drivetrain_high_low, kf_drivetrain_high_high],
-      namespaces = namespaces)
-  kf_loop_writer.Write(kf_drivetrain_files[0], kf_drivetrain_files[1])
+    kf_loop_writer = control_loop.ControlLoopWriter(
+        "KFDrivetrain", [
+            kf_drivetrain_low_low, kf_drivetrain_low_high,
+            kf_drivetrain_high_low, kf_drivetrain_high_high
+        ],
+        namespaces=namespaces)
+    kf_loop_writer.Write(kf_drivetrain_files[0], kf_drivetrain_files[1])
+
 
 def PlotDrivetrainMotions(drivetrain_params):
-  # Simulate the response of the system to a step input.
-  drivetrain = Drivetrain(left_low=False, right_low=False, drivetrain_params=drivetrain_params)
-  simulated_left = []
-  simulated_right = []
-  for _ in xrange(100):
-    drivetrain.Update(numpy.matrix([[12.0], [12.0]]))
-    simulated_left.append(drivetrain.X[0, 0])
-    simulated_right.append(drivetrain.X[2, 0])
+    # Simulate the response of the system to a step input.
+    drivetrain = Drivetrain(
+        left_low=False, right_low=False, drivetrain_params=drivetrain_params)
+    simulated_left = []
+    simulated_right = []
+    for _ in xrange(100):
+        drivetrain.Update(numpy.matrix([[12.0], [12.0]]))
+        simulated_left.append(drivetrain.X[0, 0])
+        simulated_right.append(drivetrain.X[2, 0])
 
-  pylab.rc('lines', linewidth=4)
-  pylab.plot(range(100), simulated_left, label='left position')
-  pylab.plot(range(100), simulated_right, 'r--', label='right position')
-  pylab.suptitle('Acceleration Test\n12 Volt Step Input')
-  pylab.legend(loc='lower right')
-  pylab.show()
+    pylab.rc('lines', linewidth=4)
+    pylab.plot(range(100), simulated_left, label='left position')
+    pylab.plot(range(100), simulated_right, 'r--', label='right position')
+    pylab.suptitle('Acceleration Test\n12 Volt Step Input')
+    pylab.legend(loc='lower right')
+    pylab.show()
 
-  # Simulate forwards motion.
-  drivetrain = Drivetrain(left_low=False, right_low=False, drivetrain_params=drivetrain_params)
-  close_loop_left = []
-  close_loop_right = []
-  left_power = []
-  right_power = []
-  R = numpy.matrix([[1.0], [0.0], [1.0], [0.0]])
-  for _ in xrange(300):
-    U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat),
-                   drivetrain.U_min, drivetrain.U_max)
-    drivetrain.UpdateObserver(U)
-    drivetrain.Update(U)
-    close_loop_left.append(drivetrain.X[0, 0])
-    close_loop_right.append(drivetrain.X[2, 0])
-    left_power.append(U[0, 0])
-    right_power.append(U[1, 0])
+    # Simulate forwards motion.
+    drivetrain = Drivetrain(
+        left_low=False, right_low=False, drivetrain_params=drivetrain_params)
+    close_loop_left = []
+    close_loop_right = []
+    left_power = []
+    right_power = []
+    R = numpy.matrix([[1.0], [0.0], [1.0], [0.0]])
+    for _ in xrange(300):
+        U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat), drivetrain.U_min,
+                       drivetrain.U_max)
+        drivetrain.UpdateObserver(U)
+        drivetrain.Update(U)
+        close_loop_left.append(drivetrain.X[0, 0])
+        close_loop_right.append(drivetrain.X[2, 0])
+        left_power.append(U[0, 0])
+        right_power.append(U[1, 0])
 
-  pylab.plot(range(300), close_loop_left, label='left position')
-  pylab.plot(range(300), close_loop_right, 'm--', label='right position')
-  pylab.plot(range(300), left_power, label='left power')
-  pylab.plot(range(300), right_power, '--', label='right power')
-  pylab.suptitle('Linear Move\nLeft and Right Position going to 1')
-  pylab.legend()
-  pylab.show()
+    pylab.plot(range(300), close_loop_left, label='left position')
+    pylab.plot(range(300), close_loop_right, 'm--', label='right position')
+    pylab.plot(range(300), left_power, label='left power')
+    pylab.plot(range(300), right_power, '--', label='right power')
+    pylab.suptitle('Linear Move\nLeft and Right Position going to 1')
+    pylab.legend()
+    pylab.show()
 
-  # Try turning in place
-  drivetrain = Drivetrain(drivetrain_params=drivetrain_params)
-  close_loop_left = []
-  close_loop_right = []
-  R = numpy.matrix([[-1.0], [0.0], [1.0], [0.0]])
-  for _ in xrange(200):
-    U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat),
-                   drivetrain.U_min, drivetrain.U_max)
-    drivetrain.UpdateObserver(U)
-    drivetrain.Update(U)
-    close_loop_left.append(drivetrain.X[0, 0])
-    close_loop_right.append(drivetrain.X[2, 0])
+    # Try turning in place
+    drivetrain = Drivetrain(drivetrain_params=drivetrain_params)
+    close_loop_left = []
+    close_loop_right = []
+    R = numpy.matrix([[-1.0], [0.0], [1.0], [0.0]])
+    for _ in xrange(200):
+        U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat), drivetrain.U_min,
+                       drivetrain.U_max)
+        drivetrain.UpdateObserver(U)
+        drivetrain.Update(U)
+        close_loop_left.append(drivetrain.X[0, 0])
+        close_loop_right.append(drivetrain.X[2, 0])
 
-  pylab.plot(range(200), close_loop_left, label='left position')
-  pylab.plot(range(200), close_loop_right, label='right position')
-  pylab.suptitle('Angular Move\nLeft position going to -1 and right position going to 1')
-  pylab.legend(loc='center right')
-  pylab.show()
+    pylab.plot(range(200), close_loop_left, label='left position')
+    pylab.plot(range(200), close_loop_right, label='right position')
+    pylab.suptitle(
+        'Angular Move\nLeft position going to -1 and right position going to 1'
+    )
+    pylab.legend(loc='center right')
+    pylab.show()
 
-  # Try turning just one side.
-  drivetrain = Drivetrain(drivetrain_params=drivetrain_params)
-  close_loop_left = []
-  close_loop_right = []
-  R = numpy.matrix([[0.0], [0.0], [1.0], [0.0]])
-  for _ in xrange(300):
-    U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat),
-                   drivetrain.U_min, drivetrain.U_max)
-    drivetrain.UpdateObserver(U)
-    drivetrain.Update(U)
-    close_loop_left.append(drivetrain.X[0, 0])
-    close_loop_right.append(drivetrain.X[2, 0])
+    # Try turning just one side.
+    drivetrain = Drivetrain(drivetrain_params=drivetrain_params)
+    close_loop_left = []
+    close_loop_right = []
+    R = numpy.matrix([[0.0], [0.0], [1.0], [0.0]])
+    for _ in xrange(300):
+        U = numpy.clip(drivetrain.K * (R - drivetrain.X_hat), drivetrain.U_min,
+                       drivetrain.U_max)
+        drivetrain.UpdateObserver(U)
+        drivetrain.Update(U)
+        close_loop_left.append(drivetrain.X[0, 0])
+        close_loop_right.append(drivetrain.X[2, 0])
 
-  pylab.plot(range(300), close_loop_left, label='left position')
-  pylab.plot(range(300), close_loop_right, label='right position')
-  pylab.suptitle('Pivot\nLeft position not changing and right position going to 1')
-  pylab.legend(loc='center right')
-  pylab.show()
+    pylab.plot(range(300), close_loop_left, label='left position')
+    pylab.plot(range(300), close_loop_right, label='right position')
+    pylab.suptitle(
+        'Pivot\nLeft position not changing and right position going to 1')
+    pylab.legend(loc='center right')
+    pylab.show()