1. An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
An open SOC platform for advanced machine
Overview
control
Introduction
Application
Control loop dr.ir. Peter Slaets ing. Free Claessens
Encoder
interface
Conclusions Groep T Leuven Engineering College
Questions
26 september 2008

2. Overview
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing. 1 Introduction
Free Claessens
Overview
Introduction 2 Application
Application Control loop executed on FPGA
Control loop
Encoder Encoder interface
interface
Conclusions
Questions
3 Conclusions

3. Academic research group
An open SOC
platform for
advanced Research group on robotics at the department of mechanical
machine
control
engineering of the K.U.Leuven
dr.ir. Peter
Slaets, ing. Problems
Free Claessens
Overview
Commercial robot controllers are limited w.r.t.
Introduction speed/complexity/modularity
Application Commercial robot controllers are closed
Control loop
Encoder
interface
(software/hardware)
Conclusions
Questions
Solution
Construct a fast, open robot controller yourself
Hack the robot

4. Current machine controllers
An open SOC
platform for Problems
advanced
machine
control
Closed software
dr.ir. Peter
Slaets, ing. Expensive hardware: microcontroller/DSP data-acquisition
Free Claessens
cards/. . .
Overview
Specific data-acquisition cards are hard to get
Introduction
Application
Control loop
Encoder Solution
interface
Conclusions
Open software (OROCOS)
Questions
Embedded system: computer system build on single PCB
(SOC) adaptable to specific applications
Additional advantages: power consumption, size, weight
and flexibility

5. Embedded system
An open SOC
platform for Problems
advanced
machine
control Advanced industrial applications requires a lot of
dr.ir. Peter computational power
Slaets, ing.
Free Claessens
Embedded processors gets overcharged
Overview
Hard real-time behavior becomes critical
Introduction
Application
Control loop Solution
Encoder
interface
Conclusions Embedded system based on hardware/software
Questions co-design
Tasks divided between software (processor) and hardware
(FPGA)
Processor is discharged from time critical processes by
FPGA

6. Experimental setup
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
Overview
Introduction
Application
Control loop
Encoder
interface
Conclusions
Questions

7. Architecture of hardware/software co-design
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
Overview
Introduction
Application
Control loop
Encoder
interface
Conclusions
Questions

8. Control loop executed on FPGA
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
Overview
Introduction
Application
Control loop
Encoder
interface
Conclusions
Questions

9. Block diagram of encoder interface
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
Overview
Introduction
Application
Control loop
Encoder
interface
Conclusions
Targets
Questions
Filter and decode encoder signals
Determine position, speed en acceleration of robot axes

10. Conclusions
An open SOC
platform for
advanced
machine Future work
control
dr.ir. Peter
Slaets, ing.
Implement velocity control
Free Claessens
Use software: OROCOS and Kinematics and Dynamics
Overview Library (KDL)
Introduction
Application
Control loop
Encoder
Results
interface
Conclusions Low cost robot controller (approx. 1000 e)
Questions
Open platform, exchangeable between various machines
Extension with extra sensors, like distance-, force- en
vision sensors

11. Questions
An open SOC
platform for
advanced
machine
control
dr.ir. Peter
Slaets, ing.
Free Claessens
Overview
Introduction
Application
Control loop
Encoder
interface
Conclusions
Questions
Questions, remarks?