예제 #1
0
def findMaxForce(theta1, theta2, theta3):
    theta12 = theta2 + theta1
    theta123 = theta3 + theta12
    s1 = sin(theta1)
    s2 = sin(theta2)
    s3 = sin(theta3)
    s12 = sin(theta12)
    s123 = sin(theta123)
    c1 = cos(theta1)
    c2 = cos(theta2)
    c3 = cos(theta3)
    c12 = cos(theta12)
    c123 = cos(theta123)

    J = np.array([[
        -l_1 * s1 - l_2 * s12 - l_3 * s123, -l_2 * s12 - l_3 * s123,
        -l_3 * s123
    ], [l_1 * c1 + l_2 * c12 + l_3 * c123, l_2 * c12 + l_3 * c123,
        l_3 * c123]])

    tau1 = (
        -l_1 * c1 * m_2 * g  # torque due to l_1 - l_2 link motor
        + (-l_1 * c1 + l_2 / 2.0 * c12) * m_m *
        g  # torque due to battery link motor
        + (-l_1 * c1 + l_2 / 2.0 * c12 + l_b * cos(theta12 + np.pi / 2.0)) *
        m_b * g  # torque due to battery
        + (-l_1 * c1 + l_2) * m_3 * g  # torque due to l_2 - l_3 link motor
        + (-l_1 * c1 + l_2 + l_3 * c3) * m_w * g  # torque due to front wheel
    )

    # print("tau1 = " + str(tau1))

    mp = MathematicalProgram()

    tau23 = mp.NewContinuousVariables(2, "tau23")
    tau123 = np.append(tau1, tau23)
    mp.AddCost(J.dot(tau123)[0])
    mp.AddConstraint(tau23[0]**2 <= LINK_MOTOR_CONTINUOUS_STALL_TORQUE**2)
    mp.AddConstraint(tau23[1]**2 <= LINK_MOTOR_CONTINUOUS_STALL_TORQUE**2)
    mp.AddLinearConstraint(J.dot(tau123)[1] >= -HUB_MOTOR_FORCE / 2.0)

    result = Solve(mp)
    is_success = result.is_success()
    torques = result.GetSolution(tau23)
    full_tau = np.append(tau1, torques)
    output_force = J.dot(full_tau)
    # print("is_success = " + str(is_success))
    # print("tau = " + str(full_tau))
    # print("F = " + str(J.dot(full_tau)))
    return is_success, output_force, torques
def minimize_height(diagram_f, plant_f, d_context_f, frame_list):
    """Fragile and slow :("""
    context_f = plant_f.GetMyContextFromRoot(d_context_f)
    diagram_ad = diagram_f.ToAutoDiffXd()
    plant_ad = diagram_ad.GetSubsystemByName(plant_f.get_name())
    d_context_ad = diagram_ad.CreateDefaultContext()
    d_context_ad.SetTimeStateAndParametersFrom(d_context_f)
    context_ad = plant_ad.GetMyContextFromRoot(d_context_ad)

    def prepare_plant_and_context(z):
        if z.dtype == float:
            plant, context = plant_f, context_f
        else:
            plant, context = plant_ad, context_ad
        set_frame_heights(plant, context, frame_list, z)
        return plant, context

    prog = MathematicalProgram()
    num_z = len(frame_list)
    z_vars = prog.NewContinuousVariables(num_z, "z")
    q0 = plant_f.GetPositions(context_f)
    z0 = get_frame_heights(plant_f, context_f, frame_list)
    cost = prog.AddCost(np.sum(z_vars))
    prog.AddBoundingBoxConstraint([0.01] * num_z, [5.] * num_z, z_vars)
    # # N.B. Cannot use AutoDiffXd due to cylinders.
    distance = MinimumDistanceConstraint(plant=plant_f,
                                         plant_context=context_f,
                                         minimum_distance=0.05)

    def distance_with_z(z):
        plant, context = prepare_plant_and_context(z)
        q = plant.GetPositions(context)
        return distance.Eval(q)

    prog.AddConstraint(distance_with_z,
                       lb=distance.lower_bound(),
                       ub=distance.upper_bound(),
                       vars=z_vars)

    result = Solve(prog, initial_guess=z0)
    assert result.is_success()
    z = result.GetSolution(z_vars)
    set_frame_heights(plant_f, context_f, frame_list, z)
    q = plant_f.GetPositions(context_f)
    return q
예제 #3
0
def main():
    parser = ArgumentParser()
    parser.add_argument('--datapath', default='../out/data.npy')
    parser.add_argument('--normalize', dest='normalize', action='store_true')
    parser.add_argument('--no-normalize',
                        dest='normalize',
                        action='store_false')
    parser.set_defaults(normalize=True)
    opts = parser.parse_args()

    data = dynamics.unmarshal_data(np.load(opts.datapath))
    n = data.poslambdas.shape[0]

    lambdas = np.vstack((data.poslambdas, data.neglambdas, data.gammas))
    ds = np.vstack((data.xdots, data.us, np.ones(data.xdots.shape)))

    mp = MathematicalProgram()
    M = mp.NewContinuousVariables(3, 3, "M")
    W = mp.NewContinuousVariables(3, 3, "W")
    W[0, 2] = 0
    W[1, 2] = 0

    R = M.dot(lambdas) + W.dot(ds)
    elementwise_positive_constraint(mp, R)

    lambdas_vec = np.expand_dims(np.ndarray.flatten(lambdas), 0)
    R_vec = np.ndarray.flatten(R)
    mp.AddLinearCost(lambdas_vec.dot(R_vec)[0])

    result = Solve(mp)
    print(result.is_success())

    Msol = result.GetSolution(M)

    # When mix 0's in with W, need to evaluate expression
    evaluator = np.vectorize(lambda x: x.Evaluate())
    Wsol = evaluator(result.GetSolution(W))
    print(Msol)
    print(Wsol)
예제 #4
0
    def calcTorqueOutput(self, context, output):
        q_v = self.EvalVectorInput(context, self.input_q_v_idx).get_value()
        if self.is_wbc:
            r = self.EvalVectorInput(context, self.input_r_des_idx).get_value()
            rd = self.EvalVectorInput(context,
                                      self.input_rd_des_idx).get_value()
            rdd = self.EvalVectorInput(context,
                                       self.input_rdd_des_idx).get_value()
            V = lambda x, u: self.V_full(x, u, r, rd, rdd)
            q_des = self.EvalVectorInput(context,
                                         self.input_q_des_idx).get_value()
            v_des = self.EvalVectorInput(context,
                                         self.input_v_des_idx).get_value()
            vd_des = self.EvalVectorInput(context,
                                          self.input_vd_des_idx).get_value()
        else:
            y_des = self.EvalVectorInput(context,
                                         self.input_y_des_idx).get_value()
            V = lambda x, u: self.V_full(x, u, y_des)
            q_des = self.q_nom
            v_des = [0.0] * self.plant.num_velocities()
            vd_des = [0.0] * self.plant.num_velocities()
        current_plant_context = self.plant.CreateDefaultContext()
        self.plant.SetPositionsAndVelocities(current_plant_context, q_v)

        start_formulate_time = time.time()
        prog = self.create_qp1(current_plant_context, V, q_des, v_des, vd_des)
        if not prog:
            print("Invalid program!")
            output.SetFromVector([0] * self.plant.num_actuated_dofs())
            return
        # print(f"Formulate time: {time.time() - start_formulate_time}s")
        start_solve_time = time.time()
        result = Solve(prog)
        # print(f"Solve time: {time.time() - start_solve_time}s")
        if not result.is_success():
            print(f"FAILED")
            output.SetFromVector([0] * self.plant.num_actuated_dofs())
        # print(f"Cost: {result.get_optimal_cost()}")
        qdd_sol = result.GetSolution(self.qdd)
        lambd_sol = result.GetSolution(self.lambd)
        x_sol = result.GetSolution(self.x)
        u_sol = result.GetSolution(self.u)
        beta_sol = result.GetSolution(self.beta)
        eta_sol = result.GetSolution(self.eta)

        tau = self.tau(qdd_sol, lambd_sol)
        output.SetFromVector(tau)
예제 #5
0
 def generate(self):
     self.result = Solve(self.prog)
     assert (self.result.is_success())
예제 #6
0
class PPTrajectory():
    def __init__(self, sample_times, num_vars, degree, continuity_degree):
        self.sample_times = sample_times
        self.n = num_vars
        self.degree = degree

        self.prog = MathematicalProgram()
        self.coeffs = []
        for i in range(len(sample_times)):
            self.coeffs.append(
                self.prog.NewContinuousVariables(num_vars, degree + 1, "C"))
        self.result = None

        # Add continuity constraints
        for s in range(len(sample_times) - 1):
            trel = sample_times[s + 1] - sample_times[s]
            coeffs = self.coeffs[s]
            for var in range(self.n):
                for deg in range(continuity_degree + 1):
                    # Don't use eval here, because I want left and right
                    # values of the same time
                    left_val = 0
                    for d in range(deg, self.degree + 1):
                        left_val += coeffs[var, d]*np.power(trel, d-deg) * \
                               math.factorial(d)/math.factorial(d-deg)
                    right_val = self.coeffs[s + 1][var,
                                                   deg] * math.factorial(deg)
                    self.prog.AddLinearConstraint(left_val == right_val)

        # Add cost to minimize highest order terms
        for s in range(len(sample_times) - 1):
            self.prog.AddQuadraticCost(np.eye(num_vars), np.zeros(
                (num_vars, 1)), self.coeffs[s][:, -1])

    def eval(self, t, derivative_order=0):
        if derivative_order > self.degree:
            return 0

        s = 0
        while s < len(self.sample_times) - 1 and t >= self.sample_times[s + 1]:
            s += 1
        trel = t - self.sample_times[s]

        if self.result is None:
            coeffs = self.coeffs[s]
        else:
            coeffs = self.result.GetSolution(self.coeffs[s])

        deg = derivative_order
        val = 0 * coeffs[:, 0]
        for var in range(self.n):
            for d in range(deg, self.degree + 1):
                val[var] += coeffs[var, d]*np.power(trel, d-deg) * \
                       math.factorial(d)/math.factorial(d-deg)

        return val

    def add_constraint(self, t, derivative_order, lb, ub=None):
        '''
        Adds a constraint of the form d^deg lb <= x(t) / dt^deg <= ub
        '''
        if ub is None:
            ub = lb

        assert (derivative_order <= self.degree)
        val = self.eval(t, derivative_order)
        self.prog.AddLinearConstraint(val, lb, ub)

    def generate(self):
        self.result = Solve(self.prog)
        assert (self.result.is_success())
예제 #7
0
prog = MathematicalProgram()
x = prog.NewContinuousVariables(2, "x")
y = prog.NewContinuousVariables(3, "y")

bounding_box = prog.AddLinearConstraint(x[1] <= 2)
linear_eq = prog.AddLinearConstraint(x[1] + 2 * y[2] == 1)
linear_ineq = prog.AddLinearConstraint(x[1] + 4 * y[1] >= 2)

# New program, all the way to solving...
prog = MathematicalProgram()
# Declare x as decision variables.
x = prog.NewContinuousVariables(4)
# Add linear costs. To show that calling AddLinearCosts results in the sum of each individual
# cost, we add two costs -3x[0] - x[1] and -5x[2]-x[3]+2
prog.AddLinearCost(-3*x[0] -x[1])
prog.AddLinearCost(-5*x[2] - x[3] + 2)
# Add linear equality constraint 3x[0] + x[1] + 2x[2] == 30
prog.AddLinearConstraint(3*x[0] + x[1] + 2*x[2] == 30)
# Add Linear inequality constraints
prog.AddLinearConstraint(2*x[0] + x[1] + 3*x[2] + x[3] >= 15)
prog.AddLinearConstraint(2*x[1] + 3*x[3] <= 25)
# Add linear inequality constraint -100 <= x[0] + 2x[2] <= 40
prog.AddLinearConstraint(A=[[1., 2.]], lb=[-100], ub=[40], vars=[x[0], x[2]])
prog.AddBoundingBoxConstraint(0, np.inf, x)
prog.AddLinearConstraint(x[1] <= 10)

# Now solve the program.
result = Solve(prog)
print(f"Is solved successfully: {result.is_success()}")
print(f"x optimal value: {result.GetSolution(x)}")
print(f"optimal cost: {result.get_optimal_cost()}")
 def generate(self):
     self.result = Solve(self.prog)
     assert(self.result.is_success())
class PPTrajectory():
    def __init__(self, sample_times, num_vars, degree, continuity_degree):
        self.sample_times = sample_times
        self.n = num_vars
        self.degree = degree

        self.prog = MathematicalProgram()
        self.coeffs = []
        for i in range(len(sample_times)):
            self.coeffs.append(self.prog.NewContinuousVariables(
                num_vars, degree+1, "C"))
        self.result = None

        # Add continuity constraints
        for s in range(len(sample_times)-1):
            trel = sample_times[s+1]-sample_times[s]
            coeffs = self.coeffs[s]
            for var in range(self.n):
                for deg in range(continuity_degree+1):
                    # Don't use eval here, because I want left and right
                    # values of the same time
                    left_val = 0
                    for d in range(deg, self.degree+1):
                        left_val += coeffs[var, d]*np.power(trel, d-deg) * \
                               math.factorial(d)/math.factorial(d-deg)
                    right_val = self.coeffs[s+1][var, deg]*math.factorial(deg)
                    self.prog.AddLinearConstraint(left_val == right_val)

        # Add cost to minimize highest order terms
        for s in range(len(sample_times)-1):
            self.prog.AddQuadraticCost(np.eye(num_vars),
                                       np.zeros((num_vars, 1)),
                                       self.coeffs[s][:, -1])

    def eval(self, t, derivative_order=0):
        if derivative_order > self.degree:
            return 0

        s = 0
        while s < len(self.sample_times)-1 and t >= self.sample_times[s+1]:
            s += 1
        trel = t - self.sample_times[s]

        if self.result is None:
            coeffs = self.coeffs[s]
        else:
            coeffs = self.result.GetSolution(self.coeffs[s])

        deg = derivative_order
        val = 0*coeffs[:, 0]
        for var in range(self.n):
            for d in range(deg, self.degree+1):
                val[var] += coeffs[var, d]*np.power(trel, d-deg) * \
                       math.factorial(d)/math.factorial(d-deg)

        return val

    def add_constraint(self, t, derivative_order, lb, ub=None):
        '''
        Adds a constraint of the form d^deg lb <= x(t) / dt^deg <= ub
        '''
        if ub is None:
            ub = lb

        assert(derivative_order <= self.degree)
        val = self.eval(t, derivative_order)
        self.prog.AddLinearConstraint(val, lb, ub)

    def generate(self):
        self.result = Solve(self.prog)
        assert(self.result.is_success())
예제 #10
0
                                                     size=3)).ToQuaternion()))

        # Project to nonpenetration to seed sim
        q0 = mbp.GetPositions(mbp_context).copy()
        ik = InverseKinematics(mbp, mbp_context)
        q_dec = ik.q()
        prog = ik.prog()

        constraint = ik.AddMinimumDistanceConstraint(0.01)
        prog.AddQuadraticErrorCost(np.eye(q0.shape[0]) * 1.0, q0, q_dec)
        mbp.SetPositions(mbp_context, q0)

        prog.SetInitialGuess(q_dec, q0)
        print("Solving")
        print("Initial guess: ", q0)
        res = Solve(prog)
        #print(prog.GetSolverId().name())
        q0_proj = res.GetSolution(q_dec)
        print("Final: ", q0_proj)

        mbp.SetPositions(mbp_context, q0_proj)

        simulator = Simulator(diagram, diagram_context)
        simulator.set_publish_every_time_step(False)
        simulator.set_target_realtime_rate(1.0)
        try:
            simulator.AdvanceTo(2.0)
        except Exception as e:
            print("Exception in sim: ", e)
            scene_k -= 1
    def __init__(self,
                 A,
                 B,
                 C,
                 K,
                 T,
                 Sigma,
                 x0,
                 x_lb,
                 x_ub,
                 check_states=[],
                 noise_trunc=[]):
        n = A.shape[0]  # n states

        if (len(check_states) == 0):
            check_states = range(0, n)
        if (len(noise_trunc) == 0):
            # set default to 3 std's
            noise_trunc = np.diag(Sigma)**(0.5) * 3.

        invsig = np.linalg.inv(Sigma)
        #Q = block_diag(*([invsig]*T))  #  [n1,n2,...,nL]*[Q]*[n1;n2;...;nL]
        b = np.zeros((n, 1))  #n*T

        costs = []
        eval_n_is = []

        for prob_len in range(1, T):
            for bound in ['lo', 'hi']:
                for state in check_states:
                    self.prog = MathematicalProgram()
                    # the noise decision variables, we search for the first time it falsifies.
                    # to not overconstrain the problem, if we are checking to falsify at t=i,
                    # we do not want more constraints in i:T because maybe a better probability cost will be
                    # that i,i+1,i+2 will go out of bounds, and then i+3 comes back, etc ...
                    self.n_i = self.prog.NewContinuousVariables(
                        n * prob_len, 'n')
                    # the states as a function of time
                    self.x = self.prog.NewIndeterminates(n * prob_len, 'x')

                    # the maximum value allowed for a noise measurement (truncated normal distribution)
                    for i, noise in enumerate(self.n_i):
                        self.prog.AddConstraint(noise, -noise_trunc[i % n],
                                                noise_trunc[i % n])

                    # simulate the dynamics forward to obtain the constraints on the states
                    # Drake will convert them to constraints on the decision variables
                    x_t = x0.copy()
                    for t in range(1, prob_len + 1):
                        # which noise variables affect this step
                        ind = np.arange((t - 1) * n, t * n)
                        #import pdb; pdb.set_trace()
                        x_t = (A - B * K.dot(C)).dot(x_t) - B.dot(K).dot(
                            self.n_i[ind].reshape(n, -1))
                        # the falsifying constraint:
                        if (prob_len == t):
                            for state_i in range(n):
                                dv_exist = (len(x_t[state_i][0].GetVariables())
                                            > 0)
                                if (state_i == state and dv_exist):
                                    if (bound == 'lo'):
                                        #print('adding a lower violation constraint state=%d t=%d' %(state_i, t))
                                        # hits the lower bound
                                        self.prog.AddConstraint(
                                            x_t[state_i][0] <= x_lb[state_i][0]
                                        )
                                    else:
                                        #print('adding an upper violation constraint state=%d t=%d' %(state_i, t))
                                        # hits the upper bound
                                        self.prog.AddConstraint(
                                            x_t[state_i][0] >= x_ub[state_i][0]
                                        )
                                elif (state_i != state and dv_exist):
                                    # keep it within the bounds (satisfying)
                                    self.prog.AddConstraint(
                                        x_t[state_i][0] >= x_lb[state_i][0])
                                    self.prog.AddConstraint(
                                        x_t[state_i][0] <= x_ub[state_i][0])
                                else:
                                    # dv_exist == False =>
                                    # drake cannot get a constraint in the form of const <=> const
                                    pass
                        else:
                            for state_i in range(n):
                                dv_exist = (len(x_t[state_i][0].GetVariables())
                                            > 0)
                                if (dv_exist):
                                    # the "box"/corridor constraint
                                    self.prog.AddConstraint(
                                        x_t[state_i][0], x_lb[state_i][0],
                                        x_ub[state_i][0])

                        # quadratic cost of the log likelihood
                        self.prog.AddQuadraticCost(invsig, b, self.n_i[ind])

                    # solve the mathematical program
                    result = Solve(self.prog)

                    if (result.is_success()):
                        eval_n_i = result.GetSolution(self.n_i)
                        eval_n_is.append(eval_n_i.reshape(prob_len, n).T)
                        # minus because the real cost is -1/2*x'Sx and for the prog I multiply by -1 to get max
                        # this is the true multivariate pdf
                        Q = block_diag(
                            *([invsig] *
                              prob_len))  #  [n1,n2,...,nL]*[Q]*[n1;n2;...;nL]
                        cost = (2.*np.pi)**(-(n*prob_len)/2.) * np.linalg.det(Q)**(-0.5) * \
                          np.exp(-0.5*eval_n_i.T.dot(Q).dot(eval_n_i))
                        costs.append(cost)
                        print(
                            'found solution (lh/step/state/cost %s/%d/%d/%.2e)'
                            % (bound, prob_len, state, cost))
                    else:
                        print('nope :( (lh/step/state %s/%d/%d)' %
                              (bound, prob_len, state))

        costs = np.array(costs)
        if (len(costs) > 0):
            ind = np.argmax(costs)
            # the index step, the actual cost and the whole series of noises
            self.ind = ind
            self.max_cost = costs[ind]
            self.noise_seq = eval_n_is[ind]
        else:
            self.ind = -1
            self.max_cost = -1
            self.noise_seq = np.array([])
예제 #12
0
prog = MathematicalProgram()
q = prog.NewContinuousVariables(plant_f.num_positions())

# Define nominal configuration
q0 = np.zeros(plant_f.num_positions())

# Add basic cost. (This will be parsed into a quadratic cost)
prog.AddCost((q - q0).dot(q - q0))

# Add constraint based on custom evaluator.
prog.AddConstraint(link_7_distance_to_target_vector,
                   lb=[0.1],
                   ub=[0.2],
                   vars=q)

result = Solve(prog, initial_guess=q0)

print(f"Success? {result.is_success()}")
print(result.get_solution_result())
q_sol = result.GetSolution(q)
print(q_sol)

prog = MathematicalProgram()

q = prog.NewContinuousVariables(plant_f.num_positions())
# Define nominal configuration.
q0 = np.zeros(plant_f.num_positions())

# Add custom cost.
prog.AddCost(link_7_distance_to_target, vars=q)
        dircol.AddQuadraticCost(Q=np.array([[1., 0., 0.], [0., 1., 0.],
                                            [0., 0., 1.]]),
                                b=np.array([1., 1., 1.]),
                                c=1.,
                                vars=P[:3])

        #Initial Trajectory
        initial_x_trajectory = PiecewisePolynomial.FirstOrderHold(
            [0., 20.], np.column_stack((initial_state, final_state)))
        print(initial_x_trajectory)
        dircol.SetInitialTrajectory(PiecewisePolynomial(),
                                    initial_x_trajectory)

        #Solve the DirCol
        result = Solve(dircol)
        print("\n\n")
        print("THE FUNCTION RETURN")
        print(result.is_success())
        print("\n\n")
        assert (result.is_success())

        #Final Trajectory
        print("\n\n")
        print("THE STATE TRAJ PRINT")
        u_trajectory = dircol.ReconstructInputTrajectory(result)
        x_trajectory = dircol.ReconstructStateTrajectory(result)

        #For the input u times 100
        times_input = np.linspace(u_trajectory.start_time(),
                                  u_trajectory.end_time(), 100)
예제 #14
0
point_x, = ax.plot(x_init[0], x_init[1], 'x')
ax.axis('equal')


def update(x):
    global iter_count
    point_x.set_xdata(x[0])
    point_x.set_ydata(x[1])
    ax.set_title(f"iteration {iter_count}")
    fig.canvas.draw()
    fig.canvas.flush_events()
    # Update iter_counter
    iter_count += 1
    plt.pause(1.0)


# Add a visualization callback - it does more than just visualization
iter_count = 0
prog.AddVisualizationCallback(update, x)

# Solve the optimization problem - optional second argument is initial guess. Third argument is solver parameters
result = Solve(prog, x_init, None)
# Print the result
print("Success? ", result.is_success())
# Print the solution
print("x* = ", result.GetSolution(x))
# Print the optimal cost
print('optimal cost = ', result.get_optimal_cost())
# Print the name of the solver
print('solver is: ', result.get_solver_id().name())
예제 #15
0
def plot_sublevelset_expression(ax, e, vertices=51, **kwargs):
    """
    Plots the 2D sub-level set e(x) <= 1, which must contain the origin.

    Args:
        ax:       the matplotlib axis to receive the plot
        e:        a symbolic expression in two variables
        vertices: number of sample points along the boundary
        kwargs:   are passed to the matplotlib fill method

    Returns:
        the return values from matplotlib's fill command.
    """

    x = list(e.GetVariables())
    assert len(x) == 2, "e must be an expression in two variables"

    # Handle the special case where e is a degree 2 polynomial.
    if e.is_polynomial():
        p = Polynomial(e)
        if p.TotalDegree() == 2:
            env = {a: 0 for a in x}
            c = e.Evaluate(env)
            e1 = e.Jacobian(x)
            b = Evaluate(e1, env)
            e2 = Jacobian(e1, x)
            A = 0.5 * Evaluate(e2, env)
            return plot_sublevelset_quadratic(ax, A, b, c, vertices, **kwargs)

    # Find the level-set in polar coordinates, by sampling theta and
    # root-finding (on the scalar expression) to find a rplus and rminus.

    Xplus = np.empty((2, vertices))
    Xminus = np.empty((2, vertices))
    i = 0
    for theta in np.linspace(0, np.pi, vertices):
        prog = MathematicalProgram()
        r = prog.NewContinuousVariables(1, "r")[0]
        env = {x[0]: r * np.cos(theta), x[1]: r * np.sin(theta)}
        scalar = e.Substitute(env)
        b = prog.AddBoundingBoxConstraint(0, np.inf, r)
        prog.AddConstraint(scalar == 1)
        prog.AddQuadraticCost([1], [0], [r])
        prog.SetInitialGuess(r, 0.1)  # or anything non-zero.
        result = Solve(prog)
        assert result.is_success(), "Failed to find the level set"
        rplus = result.GetSolution(r)
        Xplus[0, i] = rplus * np.cos(theta)
        Xplus[1, i] = rplus * np.sin(theta)
        b.evaluator().UpdateLowerBound([-np.inf])
        b.evaluator().UpdateUpperBound([0])
        prog.SetInitialGuess(r, -0.1)  # or anything non-zero.
        result = Solve(prog)
        assert result.is_success(), "Failed to find the level set"
        rminus = result.GetSolution(r)
        Xminus[0, i] = rminus * np.cos(theta)
        Xminus[1, i] = rminus * np.sin(theta)
        i = i + 1

    return ax.fill(np.hstack((Xplus[0, :], Xminus[0, :])),
                   np.hstack((Xplus[1, :], Xminus[1, :])), **kwargs)
예제 #16
0
    # Constrain final velocity to be 0
    # for j in range(4, 8):
    # mp.AddConstraint(final_state[j] <= 0.0)
    # mp.AddConstraint(final_state[j] >= 0.0)

    # Constrain final front wheel position
    final_front_wheel_pos = eom.findFrontWheelPosition(final_state[0],
                                                       final_state[1],
                                                       final_state[2])
    # mp.AddConstraint(final_front_wheel_pos[1] <= STEP_HEIGHT - w_r)
    mp.AddConstraint(final_front_wheel_pos[1] >= STEP_HEIGHT - w_r).evaluator(
    ).set_description("Constrain final_front_wheel_pos[1] >= 0.01")

    print("Begin solving...")
    t = time.time()
    result = Solve(mp)
    solve_traj_opt_duration = time.time() - t
    print("Done solving in " + str(solve_traj_opt_duration) + "s (" +
          str(solve_traj_opt_duration / 60.0) + "m)")
    is_success = result.is_success()
    print("is_success = " + str(is_success))
    torque_over_time_star = result.GetSolution(tau234_over_time)
    state_over_time_star = result.GetSolution(state_over_time)

    time_step = 0
    last_input = 'c'
    max_time_step = len(state_over_time_star)
    while time_step < max_time_step:
        state = state_over_time_star[time_step]
        torque = np.array(
            [i.Evaluate() for i in torque_over_time_star[time_step]])