autonomous guided vehicle control system

Sure, load it up on SourceForge and tell the DARPA Grand Challenge people about it.

John Nagle

Jack wrote:

Hi John,

Does everyone in this group repost everything when replying? Anyway...

Thanks for your encouraging response, however I am looking for something more. I have received one expression of interest from one person. Perhaps I should explain a bit more about the project.

I am making a distinction between AUTOMATED and AUTONOMOUS.

By automated I mean that the AGV will work in an environment that it knows about already, probably a structured environment. This is much easier to specify and test and hence, is an ideal environment for developing and testing the navigation and control parts of the system.

In contrast, autonomous guided vehicles must work in new environments and still achieve their goals. These AGV are much harder to specify and test. But will contain control systems similar to the automated system, but with additional higher level functionality, and probably more sensors.

Hence I hoped that a shared project to robustly implement the automated part, would be of general interest. In my opinion this automated part should consist of:

Hence I hoped that a shared project to robustly implement the automated part, would be of general interest. In my opinion this automated part should consist of:

-Corba interfaces (ACE/TAO)

-a SCAAT Kalman filter (Greg Welch, 1996)

-a hardware interface computer, controlling servos and motors, and reading shaft encoders

-interfaces to environment sensors (cameras, radar, sonar, GPS, laser, whatever).

Since I am using cameras, for test purposes cameras seem a sensible default for environment sensors ( this is in a structured environment and the image processing is straight forward).

Jack Cawkwell

Jack the way I see it, is that autonomous part is very difficult. You can try and understand it from here

I'm flumuxed as to what to do about it. I can make robot, and I can put in sensors, but I can't solve that one final problem.

Anyway, I'm certainly interested in the image processing part of the autonomous vehicle. I have experience of high speed neural nets working on systems that recognise number plates on speeding cars and peoples faces. It doesn't need structured lighting so I'm bringing to the table something you may not have. The robot bits are easy - I have tools for making custom gearboxes and mechanical prototypes in as short a period as one day.

Over to you - what do you want to do?

Jack wrote:

J e7,

Yes, this is why I want to seperate out the easier automated part, common to both automated and autonomous, so leaving the difficult research parts to experimenters, who wont have to waste time on the automated part. ( the subject of the posting should have been 'automated' not 'autonomous', I miss typed it)

I have very limited experience of actual hardware, my target vehicle is a car or bus with rubber tyres on tarmac road, so I am not expecting any problems with grip. *BUT*, if you use the SCAAT Kalman filter (SK), with a PV state vector (that is Position and Velocity) then you do not need to model vehicle motion seperately. If it slides about the SK PV state vector will reflect this if the sensors feeding the SK are quick enough. I guess you need to model the vehicle dynamics simply, enough to move the steering, brake and accelerator to move the vehicle where you want from where the sensors say you are. Obviously if you cannot steer the thing because there is no grip you are lost, but if the steering just needs a lot of correction, then it might work (certainly better than an other method).

Greg Welch's example SK application is a hat that tracks the motion of a persons head using cameras sighting LEDS in the ceiling. That is, its unpredictable, there can be no model outside of the SK. As a rough guide, currently my SK filter can process about 100 observations per second on a 600Mhz processor. I expect to get perhaps as many as 800 observations per second from 4 cameras running at

This is all good stuff for the autonomous part. The project could include both, why not?

This is probably heresy in this news group ;-), but I am hoping to buy a vehicle, and get a mechanic friend to put on the controls. The project could include hardware designs as well.

I will think about it for a day or two. If I decide to go open source, then I will start to post stuff on a web site, and let people know about it. More expressions of interest would help me decide.

Jack