Tag: industrial robot controller

Hardware and Software Platforms for Industrial Robot Controllers

Aug. 2008

Gyoung Hwan Kim. Ph.D.

gyounghkim@open-robotics.com

 Questions

• State-of-art robot controllers ?
• Design concept ?
• Internals of robot controllers?
• Next robot controller ?

Robot Programming

• AL: Stanford Univ., 1981
• VAL: Unimation, 1980
• PAL: Purdue Univ., 1981
• “Robot Manipulators”, R. P. Paul, 1981
• RCCL: Purdue Univ., 1983
• Multi-RCCL: JPL, McGill Univ., 1990
  ⇒ Dead research areaNote that Samsung’s robot language is based on VAL.

Robot Control

• Kinematics-based control: independent joint control
• Dynamics-based control: ~1990
• Direct drive arms
• Flexible robot control
  ⇒ Matured research area

State-of-art Robot Controller ?

Robot Controller Developed

Robot Controller developed for SCARA and transfer robots

Design Concept ?

Internals of Robot Controllers ?

Robot Controller Structure

Servo Controller Structures

• Type 1. Drive interface board + 1-axis drives
• Type 2. Servo board + “IPM + DC-link”s
• Type 3. Servo board + IPMs + DC-link
  Note that 1-axis drive = servo processor + IPM + DC-link circuit.

 

Type 1. Servo Controller

• High-power applications.
• Conventional control scheme.
• Commercial 1-axis drives.

Type 1 Drive Interface Board
(developed and tested)

• TI TMS320F2812 DSP for linear interpolation.
• FPGA for binary rate multiplication and encoder pulse counters.
• 6 channel incremental encoder inputs (electrically isolated).
• 6 channel pulse outs for 1-axis drives (electrically isolated).

 

Type 2. Servo Controller

• High-power applications.
• Flexible control schemes.

Type 3. Servo Controller

• Low-power applications.
• Flexible control schemes.

Type 3 Servo Board

• The most powerful , flexible and advanced servo controller used in commercial industrial robot controllers.
• Software –only implementation of position, velocity, and current control.
• 1KHz current loop and 0.5 kHz position and control loop.
• DSP load is less than 30%.

Type 3 IPM
(Intelligent Power Module)

Type 3 DC-Link Circuit

Robot Controller Structure

Main Processor Board

• Hardware: X86 motherboard + PCI boards
• Software: Real-time Linux (RTAI)

CPU Board
(off-the-shelf product)

• Compact size and low power consumption: Mini-ITX board with an 1GHz VIA CPU.
• 3 PCI board using a riser card.

Riser Card for 3 PCI Slots

 PCI Boards

• High speed 4-port serial board: two RS232 ports and two RS422 ports.
• CC-link PCI board: TI TMS320C2812 DSP with a dual-port memory.
• RTAI RTDM drive driver for the serial board and Linux device driver for the CC-link board are also developed.

Four-port Serial PCI Board

CC-Link PCI Board

Profibus PCI Board

Parallel I/O board

• Intelligent parallel I/O board – TI TMS320F2812 DSP.
• Electrically isolated 24 inputs and 24 outputs.

Main-to-Servo Interface

• Main processor to servo controller interface:
  – electrically isolated.
  – high-speed (2.5M bps) serial interface – RS422.

Tested Configurations

• One SCARA robot + one X-Y robot.
• Three X-Y robots.
• One transfer robot with one driving axis.

SCARA + X-Y robots

LCD Transfer Robot with a Driving Axis

Next Robot Controllers ?

• For larger robots, a drive interface board is developed.
• If needed, RCCL can be used.

Conclusion

• A flexible robot controller is developed and tested with SCARA robots and transfer robots.