From: jwb@capek.rdt.monash.edu.au (Jim Breen)
Subject: Re: 1992 Australian MicroMouse Contest
Organization: Monash University, Melb., Australia.
Distribution: aus
Date: Tue, 3 Nov 1992 22:27:12 GMT


This year final-year students in Monash's Bachelor of Computing
(Digital Technology) course have had as their compulsory project the 
building of MicroMice capable of competing in the Oz Mouse competition.

The Department of Robotics & Digital Technology at Monash, which operates 
the Digital Technology course, will be providing the maze and timing system 
for this years' OzMouse competition.

Appended are two articles about the Digital Technology mice which have 
been distributed electronically at Monash.

=========== =========== =========== ===========
RDT MOUSE ASSESSMENT TRIALS

It was standing Standing Room Only in E403 on Friday 30 November as RDT
staff and students, and visitors from other Departments and Faculties
watched the assessment trials which were the culmination of the years'
work in RDT3360 (Digital Technology Project). The 1992 project was to
build "micromice" complying with the rules of the IEEE Micromouse
competition.

October 30 was D-Day for the 15 project groups in RDT3360. At stake was
the 60% of the marks to be gained based on the performance of their mice
(the other 40% is for the reports, seminar presentations, project diary,
peer assessment of contribution, etc.)

The marks which could be obtained on Friday were:

(a) smoothly accelerate the mouse to a command velocity, then decelerate
to a stop, all in a straight line (6%)

(b) demonstrate "wall-following" ability within the maze (24%)

(c) demonstrate ability to repeat a given path in the maze (36%)

(d) successfully move from the maze start to the goal square (i.e. solve
the maze) (48%)

(e) find the minimum time solution to the maze (60%)

Between 8am and 9am on the 30th, E403 was cleared of students (for the
first time in 60 hours) and the maze reconfigured into its unseen test
layout. This layout, devised by John Robinson, was particularly tortuous,
including all the well-known maze traps such as spirals, boxed sections
and the notorious "herring bone" pattern. At 9am the mice and their
software were handed to the stewards, the doors of E403 opened, and the
8 hour non-stop trial began.

Two of the teams had set themselves the limited (b) and (c) goals on the 
day, but most set out to attempt all stages. It was clear from the
beginning that the mice with overhanging sensor arrays were going to fare
better than those with the more challenging sideways sensors. None of this
latter group actually reached the goal, although one only crashed a few
squares away, and was awarded a (d) achievement. The `Neuromouser', which
was the pre-trial favourite in this group, having successfully negotiated
the test maze, disappointed its creators by repeating MITEE VI's antics in 
Hong Kong and attempted to drive through non-existent openings.

Almost all the mice with overhanging sensors achieved the (d) or (e) stages.
Predictably, the best performance came from `Splinter', which was the
first mouse to solve the maze in testing, and had clearly benefited from
several weeks of tuning. With its sensor arrays secured by bulldog clips,
doubtless to speed up pit stops, it's best time was 1'08", which was very 
good for a long and complicated maze.  Also performing well was `Cyberpunk' 
with 1'50" in its best run. Several others reached the goal, with `AmazeIV' 
celebrating the event by playing a tune (birthday card circuit) .

Several of the project teams will be going on to compete in OzMouse at
TENCON '92 on 11 and 12 November. A precompetition trial of these mice,
using OzMouse rules (battery power, time constraints, touching penalties, 
etc.) will be held in E403 at 11am on 6 November. Visitors are welcome.

=========== =========== =========== ===========

MICE INVADE RDT

RDT's Robotics Laboratory (E4.03) has been taken over by a 9 square metre
maze through which electro-mechanical robot "mice" can be seen at all hours
attempting to find their way through an intricate pattern of walls.

The maze will be moved to the World Trade Centre in early November where
it will be used in the OzMouse competition, co-sponsored by RDT, which is
being held in conjunction with the IEEE Tencon conference.
OzMouse is the  Australian section of the world-wide IEEE
Micromouse competition, which draws entrants from many countries to its
biennial competitions.

OzMouse competition mice must be self-contained, self powered devices which
measure no more than 25cm by 25 cm. As the maze sections are 18cm square,
this allows mice to overhang the 5cm high walls. The mice must find their
own way from the starting point at one corner to the goal in the centre,
return to the start, and then attempt a speed-run to the goal. Apart from
the size limits, mice can be of any technology, except the rules exclude
mice with "an energy source which employs a combustion source" and
requires that mice "shall not jump over, climb, scratch, damage or destroy
the maze walls", nor "leave any part of its body behind during a run".

This year's 3rd year Digital Technology project is to build mice capable
of entering in OzMouse. Fifteen mice are under construction. Students are
using a standard chassis and motor system (Akai CD player motors) designed
and built by Dr Peter Atkinson, with very welcome assistance from the
Mechanical Engineering workshop. The chassis has two independant motors
that are used for drive and steering, and castors fore and aft for balance. 

Most student teams are also using a
standard processor card designed by Mr Gary Evans. This card uses an 8MHz (2MIP)
Motorola M68HC11 processor and has 64K of RAM/ROM. Key features of the
card are the two HP motor controller chips, which allow the processor to specify
velocity and acceleration settings for the motors, and to read the motor
positions from their shaft encoders. One student team has designed its own
processor card.

The student tasks in the project have been to:

(a) design and build the sensor system which will enable the mouse to move
through the maze.

(b) interface their sensors with the processor.

(c) program the mouse to map and solve the maze.

For the students much of the sensor design was done in Semester I, where
it was part of the practical work in Digital Design III. Most teams are
using infra-red sensor-detector arrays which overhang the maze walls, and
detect the presence or absence of the wall segments. A smaller number are
using side-mounted sensors which must measure the distance to adjacent
walls, and some teams are using a mixture of the two.

Students had a choice of either C or Assembler to program the M68HC11, and about
half the teams are using each. The C cross-compiler runs on a Sun, and
the cross-assemblers on PCs. Test programs are down-loaded to the mouse
using a serial port on its processor card, and the final versions will be 
burnt in EPROMs for the competion.

Student teams have had to write every instruction of software for the
mouse, as there is no operating system, and only a crude loader for test
programs. It is an epic in real-time programming, as the mice need to
continually detect the wall locations and steer accordingly, as well as
building a map of the maze and seeking an optimal solution. The typical
mouse software is several thousand lines of C and assembler.

Mouse programming is far removed from what most people associate with
software development, as there is no input and output in the traditional
sense. Instead the software has to interact with motor controllers through
about 30 registers and with the registers interfacing the sensor system.
This is, however, typical of processors controlling devices in industrial
situations.

At the time of writing (12 October) at least one of the mice is fully
solving the maze, and is currently having its "racing turns" debugged. It
is performing as well as the place-getters in the 1991 Hong Kong competition.
Several other mice are not far behind.

D-day for the student mice will be 30 October, when they will go through
their paces under the gimlet eye of the Project Coordinator, Dr Simon
Hill. It his hoped that some of the mice will represent Monash at OzMouse
against the experienced teams from Macquarie and University of Queensland.
Unfortunately the Tencon conference is in the middle of the exams, so it
it will be understood if the students are a little distracted at that
time.
-- 
Jim Breen                           JIS:$B%8%`!!%V%j!<%s(J
Department of Robotics & Digital Technology. Monash University. 
PO Box 197 Caulfield East VIC 3145 Australia (ph) +61 3 573 2552 
(fax) +61 3 573 2345  AARNet/Internet:jwb@capek.rdt.monash.edu.au