def test_contact(self):
# PenetrationAsContactPair
point_pair = PenetrationAsPointPair()
self.assertTrue(isinstance(point_pair.id_A, GeometryId))
self.assertTrue(isinstance(point_pair.id_B, GeometryId))
self.assertTrue(point_pair.p_WCa.shape == (3, ))
self.assertTrue(point_pair.p_WCb.shape == (3, ))
self.assertTrue(isinstance(point_pair.depth, float))
# PointPairContactInfo
id_A = BodyIndex(0)
id_B = BodyIndex(1)
contact_info = PointPairContactInfo(bodyA_index=id_A,
bodyB_index=id_B,
f_Bc_W=np.array([0, 0, 1]),
p_WC=np.array([0, 0, 0]),
separation_speed=0,
slip_speed=0,
point_pair=point_pair)
self.assertTrue(isinstance(contact_info.bodyA_index(), BodyIndex))
self.assertTrue(isinstance(contact_info.bodyB_index(), BodyIndex))
self.assertTrue(contact_info.contact_force().shape == (3, ))
self.assertTrue(contact_info.contact_point().shape == (3, ))
self.assertTrue(isinstance(contact_info.slip_speed(), float))
# ContactResults
contact_results = ContactResults()
contact_results.AddContactInfo(contact_info)
self.assertTrue(contact_results.num_contacts() == 1)
self.assertTrue(
isinstance(contact_results.contact_info(0), PointPairContactInfo))
def test_contact(self):
# PenetrationAsContactPair
point_pair = PenetrationAsPointPair()
self.assertTrue(isinstance(point_pair.id_A, GeometryId))
self.assertTrue(isinstance(point_pair.id_B, GeometryId))
self.assertTrue(point_pair.p_WCa.shape == (3, ))
self.assertTrue(point_pair.p_WCb.shape == (3, ))
self.assertTrue(isinstance(point_pair.depth, float))
# PointPairContactInfo
id_A = BodyIndex(0)
id_B = BodyIndex(1)
contact_info = PointPairContactInfo(bodyA_index=id_A,
bodyB_index=id_B,
f_Bc_W=np.array([0, 0, 1]),
p_WC=np.array([0, 0, 0]),
separation_speed=0,
slip_speed=0,
point_pair=point_pair)
self.assertTrue(isinstance(contact_info.bodyA_index(), BodyIndex))
self.assertTrue(isinstance(contact_info.bodyB_index(), BodyIndex))
self.assertTrue(contact_info.contact_force().shape == (3, ))
self.assertTrue(contact_info.contact_point().shape == (3, ))
self.assertTrue(isinstance(contact_info.slip_speed(), float))
self.assertIsInstance(contact_info.point_pair(),
PenetrationAsPointPair)
# ContactResults
contact_results = ContactResults()
contact_results.AddContactInfo(contact_info)
self.assertTrue(contact_results.num_contacts() == 1)
self.assertTrue(
isinstance(contact_results.contact_info(0), PointPairContactInfo))
# ContactResultsToLcmSystem
file_name = FindResourceOrThrow(
"drake/multibody/benchmarks/acrobot/acrobot.sdf")
plant = MultibodyPlant()
Parser(plant).AddModelFromFile(file_name)
plant.Finalize()
contact_results_to_lcm = ContactResultsToLcmSystem(plant)
context = contact_results_to_lcm.CreateDefaultContext()
context.FixInputPort(0, AbstractValue.Make(contact_results))
output = contact_results_to_lcm.AllocateOutput()
contact_results_to_lcm.CalcOutput(context, output)
result = output.get_data(0)
self.assertIsInstance(result, AbstractValue)