Project Description

  • cobot joint module

Cobot Joint Module

  • Compact: compact structure and flexible design features
  • Lightweight: integrated design of motors, reducers, sensors, drives, etc.
  • Accurate: Repeated positioning accuracy higher than 0.001°
  • Powerful: The output continuous torque is 10~200N.m. Rated speeds up to 40 RPM and acceleration up to 10 RPS/S
  • Normally 48VDC power supply, 24~48VDC power supply optional
  • CAN bus, supporting most mainstream robot controllers
  • Customized development services

High Performance Cobot Joint Module

Product Summary

The cobot arm joint module consists of a servo drive, a frameless torque motor, a harmonic reducer, a photoelectric encoder (before the reducer), an absolute encoder (after the reducer, to measure the absolute angle of the output shaft of the cobot arm) ,an electronic brake and etc., which are integrated in a modular assembly,  and packaged into the joints suitable for multi-axis cobot arms, and can also be used as other automation equipment. It is featured by higher transmission efficiency, compact structure, greater continuous torque and instantaneous torque output.

With the highly integrated mechatronic designing and drive integrated designing, the cobot arm joint module can be used as the preferred product of system integrators such as industrial and service robots. The customer’s investment in the selection, design and assembly of machinery can be reduced sharply. The comprehensive cost of supply chain &quality management can be simplified.

Features

  • Compact: conforms to the industrial and service robots with compact structure and flexible design features
  • Lightweight: integrated design of motors, reducers, sensors, drives, etc. to minimize volume and quality
  • Accurate: Repeated positioning accuracy of the joint module output is higher than 0.001°
  • Powerful: The output continuous torque is 10~200N.m. Rated speeds up to 40 RPM and acceleration up to 10 RPS/S
  • Convenient: Normally 48VDC power supply, 24~48VDC power supply optional, to meet the battery-powered features of service robots
  • Open: CAN bus communication, supporting most mainstream robot controllers
  • Customized development services

Specifications & Parameters

Parameters Unit RJS14 RJS17 RJS20 RJS25 RJS32
Joint weight kG 2 2.5 3 4.5 7.5
Joint diameter mm 90 90 100 119 156
Joint height mm 100 104 114 135 172
Joint length mm 128 144 144 157 162
Rotation accuracy Arcmin 2 2 1.5 1.5 1.5
Rated speed RPM 35 30 30 25 20
Allowable

load torque

N*m 28 54 82 157 333
Average

load torque

N*m 11 39 49 108 216
Maximum instantaneous torque N*m 54 86 147 284 647
Incremental encoder P/R 2500 2500 2500 2500 2500
Absolute encoder Bit 17/19 17/19 17/19 17/19 17/19
Protection level IP54 IP54 IP54 IP54 IP54

Servo Drives for The Cobot Joint Modules

Brief Introduction

The servo drive is a new high-performance, low-voltage, DC-powered, full-closed, all-digital servo motor driver designed for the cooperative robot integrated joint module. The high-performance TITMS320F28069DSP chip is used as the main processor to realize the joint module. With the precise control of the current, speed and position of the frameless torque motor, it can also be used as a servo drive for volume requirements such as exoskeleton robots.

The peak current of the driver can reach more than three times of the rated current, with high dynamic performance, large peak torque, smooth running at low speed, strong anti-interference ability, colleagues have undervoltage, overvoltage, overload, overcurrent, stall, Hall or encoder abnormal alarm and other functions. The CAN and RS232 interfaces are used to control the drive. The performance of the mechanical arm joint servo drive reaches the level of well-known brand servo drives at home and abroad.。

The mechanical arm joint servo drive is small in size, easy to install, and easy to debug. Through the driver debugging software, the user can easily match the basic parameters of the motor and servo drive, change the motor control mode, three closed loop parameters, etc., to achieve precise control of the motor.

Technical Parameters

No. Items Description
1 Supply voltage 20-56VDC (24V, 48V battery or switching power supply is recommended, 48V battery is fully charged at about 54V, it can work normally)
2 Output current

per channel

Continuous current 6A, peak 18A (late upgrade to continuous current 15A, peak current 45A)
3 control method Serial port, CAN bus communication, support torque, speed and position mode
4 Adapter motor Low-voltage frameless torque motor or other AC servo motor, permanent magnet synchronous motor
5 Bus communication CAN bus
6 Abnormal protection Fault alarm output such as undervoltage, overvoltage, overload, overcurrent, stall, encoder abnormality
7 Dual encoder Reducer output close-loop feedback uses single-turn relative encoder, encoder 20000 ppr, mechanical arms’ joint end uses 17-bit absolute magnetic encoder, support BISS protocol, can also be customized to support SSI, SPI, 485 absolute value encoders
8 Controller Built-in trapezoidal acceleration and deceleration curve, special function customized service, forming a product integrated with drive control
9 Electromagnetic brake control Start 24VDC, keep the current down (the joint module does not add this function, you can add it later)
10 Braking resistor stand by. For applications with large inertia and large loads, it is necessary to connect a braking resistor to the power supply to protect the controller.
11 cooling method Natural cooling or external heat sink
12 Protection level IP54 (drive board with housing, heat sink); IP20 (drive board)
13 Position error

control accuracy

±10Pulse (80,000 pulses per circle)
14 Speed control

accuracy

±2rpm@1000RPM (speed closed loop mode), in position mode, can achieve better low speed performance, can control the angle of rotation with one pulse and one pulse
15 Use occasion Try to avoid dust, oil mist and corrosive gases
16 Operating temperature -20℃-70℃
17 Storage temperature -20℃-+80℃
18 Working humidity 40-90%RH
19 Vibration 5.9m/s2Max
20 Weight 0.2kg