m = Model(name="mybot") sdf = SDF(elements=[m]) geom = Box(SENSOR_BASE_THICKNESS, SENSOR_BASE_WIDTH, SENSOR_BASE_WIDTH, MASS) base = StructureCombination("base", geom) x_sensors = 0.5 * (SENSOR_BASE_THICKNESS + SENSOR_THICKNESS) y_left_sensor = -0.5 * SENSOR_WIDTH - SEPARATION y_right_sensor = 0.5 * SENSOR_WIDTH + SEPARATION left = StructureCombination("left", Box(SENSOR_THICKNESS, SENSOR_WIDTH, SENSOR_HEIGHT, MASS)) left.set_position(Vector3(x_sensors, y_left_sensor, 0)) right = StructureCombination("right", Box(SENSOR_THICKNESS, SENSOR_WIDTH, SENSOR_HEIGHT, MASS)) right.set_position(Vector3(x_sensors, y_right_sensor, 0)) link = Link("my_link") link.add_elements([base, left, right]) link.align_center_of_mass() link.calculate_inertial() m.add_element(link) apply_surface_parameters(m) m.translate(Vector3(0, 0, in_mm(30))) with open("/home/elte/.gazebo/models/test_bot/model.sdf", "w") as f: f.write(str(sdf))