UR5e (Universal Robots UR5e + Robotiq 2F-85)

The Universal Robots UR5e is a 6-DoF collaborative arm with a Robotiq 2F-85 parallel-jaw gripper. Unlike the other three robots, the UR5e is mounted on a 4-legged ur5_base (top plate at z = 0.59) with a SEPARATE cafe_table workspace at world (0.7, 0, 0) — the arm sits next to the table, not on top of it.

Tasks

Task	Env ids	Page
Reach	UR5eReacherSim-v0 / ...GoalSim-v0 / ...Real-v0 / ...GoalReal-v0	UR5e — Reach
Push	UR5ePushSim-v0 / ...GoalSim-v0 / ...Real-v0 / ...GoalReal-v0	UR5e — Push
PnP	UR5ePnPSim-v0 / ...GoalSim-v0 / ...Real-v0 / ...GoalReal-v0	UR5e — Pick-and-Place

Robot-specific facts

Topic	Value
Arm joints (6)	shoulder_pan_joint, shoulder_lift_joint, elbow_joint, wrist_1_joint, wrist_2_joint, wrist_3_joint
Gripper joints (1)	robotiq_85_left_knuckle_joint — single actuated knuckle; the other 5 finger joints follow via URDF mimic linkage
Gripper open / closed value	Open = gripper_min ≈ 0.0 rad; closed = gripper_max ≈ 0.8 rad. Opposite of the prismatic-finger convention used by RX200 / VX300S where open = gripper_max. The env reads gripper_open_value / gripper_closed_value rosparams so reward + obs code doesn’t have to know which way the bounds map.
grasp_finger_thresh semantics	INVERTED — is_grasped triggers when knuckle_pos > grasp_finger_thresh (≈ 0.4 rad)
PnP joint-mode action dim	6 (arm) + 1 (gripper scalar) = 7
Arm controller topic	/ur5e/arm_controller/command
URDF link prefix	Bare names on both sim + real (base_link, shoulder_link, …, ee_link). MoveIt SRDF group arm chains base_link → ee_link.
End-effector link (FK)	ee_link
Reference frame	base_link
MoveIt planning groups	arm, gripper (from ur5e_robotiq_85_moveit_config SRDF)
Init pose	Folded upright ([0, -π/2, π/2, -π/2, -π/2, 0]). The URDF-zero pose puts the arm horizontal at base height, colliding with the cafe-table column — sim uses SetModelConfiguration (pause → snap → unpause) to apply the safe pose before physics runs.
Safety geometry	Two-floor check: every link clears base_z = 0.59 AND only when projected over the cafe-table footprint, also clears table_top_z = 0.775. Other robots have a single table floor since they’re flush-mounted.

Sim setup

• Description-extras package: ur5e_description_extras (URDF wrap, controller config, ur5_base model, cafe_table model, red_cube model, Kinect mount, ur5e_scene.world).

• The env launches Gazebo with ur5e_scene.world (sun, ground, ur5_base, cafe_table baked in). Arm spawns at z = 0.59 on top of the base. MoveIt comes up via the ur5e_description_extras/launch/ur5e_move_group.launch wrapper (drops the un-namespaced upstream ur5e_robotiq_85_moveit_config into <group ns="ur5e">).

Real setup

• TBD: ur5e_description_extras/launch/ur5e_real.launch (to write at the lab). Expected to bring up ur_robot_driver with the calibrated UR5e network IP + a Robotiq 2F-85 driver + MoveIt under /ur5e.

• The env subscribes to /ur5e/joint_states and publishes to /ur5e/arm_controller/command + /ur5e/gripper_controller/command.

• Push / PnP subscribe to /cube_pose for cube tracking.