<< CCC << Aim | Prototype | proposed extension >>

    Last updated: 11 April 2000 &beetung <Tue> 1:25am

This section would briefly describe an existing prototype model car which I obtained from my supervisor, Prof. Lloyd Allison (CSSE), during the beginning of 2000.

This prototype is built by Tim Bruton during 1999 as his BCSE hons. A picture of it can be seen here[XXXX]. It has a CCD camera mounted on board along with a RF video modulator for video feedback. Tim has implemented a simple software navigation system utilizing a Silicon Graphics INDY for processing. His implementation make use of an existing interface between computer-controller designed previously during 1998.

This computer-controller interface was built by David Duke back in 1998 as his final year project(hons?). No documentation(neither software code, hardware specs or what-so-ever) was available on the design of his controller. This put me in a rather difficult situation when I try to "speed up" the car. Eventually, I have conducted a series of test in an attempt to reverse engineer the intrinsic natural behaviour of his controller.

 
1999 -Tim Bruton implemented (1)a on board CCD camera unit with a video RF modulator and (2)built a basic Visual Navigation System software (VNS)

1998 - David Duke built a DIN-8 Computer to RF controller interface. Car controlled via arrow keys. Require human control.
 

Prototype Specs

weight over 5 kgs?
top speed ?
battery design & consumption?
physical size?
 

Our prototype controller is built by David Duke back in 1998. We have no documentation on his design. A detailed examination on Tims code does not indicate behaviour/nature on this particular controller implementation. A sequence of test was conducted and the result would be listed below for your reference.

I have been able to identify eleven mode of controller operation. Since the original controller was intended for a DIN-8 interface rather than a RS-232,

Talk mode on RS-232 Link is standard on standard Unix tty mode which is :

· 9600,none,8,1 <baud>, <parity>, <data>, <stop>

 

Value*	Symb	Action
0	...	NIL
1		Backward
2		Forward
3		Forward (fast mode)
4		Right turn
5		Right & Back
6		Right & Forward
7		Right & Forward (fast mode)
8		Left
9		Left & Back
10		Left & Forward
11		Left & Forward (fast mode)
12	...	NIL
13		Same as 1
14		Same as 2

*value represent the value as (char) being sent to the serial port. (ie: value 0 means ’\0’)

Problem identified so far:

The response of our existing prototype is extremely slow! The latency between sending a signal and the corresponding response is unacceptably high.

This effectively limits our maximum achievable speed and can cause some major control logic hazard when our Intelligent Navigation System is later implemented. (oscillatory response could result due to large latency, we want critical response! Refer to ECS3311 notes).