2 Mitsubishi RM-501 Robot

RM-501 Robot ECE ECE 54 5463 – Fall Fall 2014 014 Read RM-501 Manual on the Course Webs We bsit itee – Chap Chapte ters rs 1 and and 2

Main Components •

RM 501 – 5 joint robot arm

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Standard hand – gripper or endeffector 

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Teach box (pendant) – for manual movement of the arm

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Drive unit – Reside all control and  power electronics

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Wrist

Computer – Use PC to output ASCII characters to a printer port to control the robot

Elbow Shoulder  Waist

Mechanical structure

Robot Unit  – Outer appearance • 5 Degrees of freedom (DOF) – waist, shoulder, elbow, pitch, roll • Base, body, upper arm, forearm, hand attachment Wrist

• The robot is in articulated geometry  – Every joint is rotational • As opposed to cylindrical or spherical

• Hand – 2 jaw gripper which uses a DC motor to control close and open

Spherical

Cylindrical

 – Interior of arm • 3 parts to each joint generally: motor (DC permanent magnet), timing  belt, appropriate gearing to reduce speed and increase torque, limit switch • Limit switch – limit the travel of a joint (small micro-switch), also used to provide a nest position • Two motors for wrist

Drive Unit  – Programs + positions may be entered into the system and stored in a ROM used in subsequent playback   – Serial port (RS232C) for connection to an external computer (like the usual terminal port)  – Centronics connection (standard connector for most printers)  – External I/O terminals – it is usually necessary to synchronize the operation of robot with convey, solenoids for part pick-up

Teach Box  – Slide switch – “on” for teaching and “off” for computer mode  – 12 keys on right for manually operating the joints • B body movement • S shoulder movement • E elbow movement • R rotation of wrist • P pitch of wrist • O open hand • C close hand

 – NST – ENT (executing the key): move to origin of the mechanical system (where the limit switches are)  – P.S. # ENT, 1 < # < 629 or # =0: store the values of the joint  positions where you are with an associated position number (stored internally in a RAM); 0 = home position  – P.C. # ENT, delete a stored position

Teach Box - continued

 – MOV # ENT: move to a recorded position  – ORG ENT: move to the home position = MOV 0  – INC (DEC) ENT: after going to a specific position, causes movement to next (previous) position  – WRT # ENT: write from RAM to ROM, 0 ≤ # ≤ 5  – TRN # ENT: write from ROM to RAM

Specifications • Robot Unit  – Range of joints • Waist: 300 • Shoulder: 130 • Elbow: 90 • Pitch:

90

• Roll:   180

 – Handling weight (payload): ≈1.2 Kg  – Speed = 400 mm/sec (> 1ft/sec)  – Repeatability = ± 0.5 mm (± 0.02 in) – the difference from absolute accuracy?  – Weight: ≈ 27 Kg  – Type of manipulation: Servo-controlled point to point

Specifications - continued • Driver Unit  – Control system: point to point  – Point position identification: optical encoder 

• Control Unit  – Z-80 microprocessor   – 2 types of interface to PC  – Teach box, ROM, I/O  – Operating system/control program memory/data memory