ex_2.py

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import time
 
import matplotlib.pyplot as plt
import numpy as np
import plot_utils as plut
import romeo_conf as conf
from numpy import nan
from numpy.linalg import norm as norm
from tsid_biped import TsidBiped
 
print("".center(conf.LINE_WIDTH, "#"))
print(" TSID - Biped Sin Tracking ".center(conf.LINE_WIDTH, "#"))
print("".center(conf.LINE_WIDTH, "#"), "\n")
 
tsid = TsidBiped(conf, conf.viewer)
 
N = conf.N_SIMULATION
com_pos = np.empty((3, N)) * nan
com_vel = np.empty((3, N)) * nan
com_acc = np.empty((3, N)) * nan
 
com_pos_ref = np.empty((3, N)) * nan
com_vel_ref = np.empty((3, N)) * nan
com_acc_ref = np.empty((3, N)) * nan
com_acc_des = np.empty((3, N)) * nan  # acc_des = acc_ref - Kp*pos_err - Kd*vel_err
 
offset = tsid.robot.com(tsid.formulation.data())
amp = np.array([0.0, 0.05, 0.0])
two_pi_f = 2 * np.pi * np.array([0.0, 0.5, 0.0])
two_pi_f_amp = two_pi_f * amp
two_pi_f_squared_amp = two_pi_f * two_pi_f_amp
 
sampleCom = tsid.trajCom.computeNext()
samplePosture = tsid.trajPosture.computeNext()
 
t = 0.0
q, v = tsid.q, tsid.v
 
for i in range(0, N):
    time_start = time.time()
 
    sampleCom.pos(offset + amp * np.sin(two_pi_f * t))
    sampleCom.vel(two_pi_f_amp * np.cos(two_pi_f * t))
    sampleCom.acc(-two_pi_f_squared_amp * np.sin(two_pi_f * t))
 
    tsid.comTask.setReference(sampleCom)
    tsid.postureTask.setReference(samplePosture)
 
    HQPData = tsid.formulation.computeProblemData(t, q, v)
    # if i == 0: HQPData.print_all()
 
    sol = tsid.solver.solve(HQPData)
    if sol.status != 0:
        print("QP problem could not be solved! Error code:", sol.status)
        break
 
    tau = tsid.formulation.getActuatorForces(sol)
    dv = tsid.formulation.getAccelerations(sol)
 
    com_pos[:, i] = tsid.robot.com(tsid.formulation.data())
    com_vel[:, i] = tsid.robot.com_vel(tsid.formulation.data())
    com_acc[:, i] = tsid.comTask.getAcceleration(dv)
    com_pos_ref[:, i] = sampleCom.pos()
    com_vel_ref[:, i] = sampleCom.vel()
    com_acc_ref[:, i] = sampleCom.acc()
    com_acc_des[:, i] = tsid.comTask.getDesiredAcceleration
 
    if i % conf.PRINT_N == 0:
        print(f"Time {t:.3f}")
        if tsid.formulation.checkContact(tsid.contactRF.name, sol):
            f = tsid.formulation.getContactForce(tsid.contactRF.name, sol)
            print(
                "\tnormal force {}: {:.1f}".format(
                    tsid.contactRF.name.ljust(20, "."), tsid.contactRF.getNormalForce(f)
                )
            )
 
        if tsid.formulation.checkContact(tsid.contactLF.name, sol):
            f = tsid.formulation.getContactForce(tsid.contactLF.name, sol)
            print(
                "\tnormal force {}: {:.1f}".format(
                    tsid.contactLF.name.ljust(20, "."), tsid.contactLF.getNormalForce(f)
                )
            )
 
        print(
            "\ttracking err {}: {:.3f}".format(
                tsid.comTask.name.ljust(20, "."), norm(tsid.comTask.position_error, 2)
            )
        )
        print(f"\t||v||: {norm(v, 2):.3f}\t ||dv||: {norm(dv):.3f}")
 
    q, v = tsid.integrate_dv(q, v, dv, conf.dt)
    t += conf.dt
 
    if i % conf.DISPLAY_N == 0:
        tsid.display(q)
 
    time_spent = time.time() - time_start
    if time_spent < conf.dt:
        time.sleep(conf.dt - time_spent)
 
# PLOT STUFF
time = np.arange(0.0, N * conf.dt, conf.dt)
 
(f, ax) = plut.create_empty_figure(3, 1)
for i in range(3):
    ax[i].plot(time, com_pos[i, :], label="CoM " + str(i))
    ax[i].plot(time, com_pos_ref[i, :], "r:", label="CoM Ref " + str(i))
    ax[i].set_xlabel("Time [s]")
    ax[i].set_ylabel("CoM [m]")
    leg = ax[i].legend()
    leg.get_frame().set_alpha(0.5)
 
(f, ax) = plut.create_empty_figure(3, 1)
for i in range(3):
    ax[i].plot(time, com_vel[i, :], label="CoM Vel " + str(i))
    ax[i].plot(time, com_vel_ref[i, :], "r:", label="CoM Vel Ref " + str(i))
    ax[i].set_xlabel("Time [s]")
    ax[i].set_ylabel("CoM Vel [m/s]")
    leg = ax[i].legend()
    leg.get_frame().set_alpha(0.5)
 
(f, ax) = plut.create_empty_figure(3, 1)
for i in range(3):
    ax[i].plot(time, com_acc[i, :], label="CoM Acc " + str(i))
    ax[i].plot(time, com_acc_ref[i, :], "r:", label="CoM Acc Ref " + str(i))
    ax[i].plot(time, com_acc_des[i, :], "g--", label="CoM Acc Des " + str(i))
    ax[i].set_xlabel("Time [s]")
    ax[i].set_ylabel("CoM Acc [m/s^2]")
    leg = ax[i].legend()
    leg.get_frame().set_alpha(0.5)
 
plt.show()