Final Contest Challenge
Winter 2005
Introduction
As part of this
freshman design course, students (working in groups of three) will design,
construct, and program a Lego RCX microprocessor-based robot. The robot has to
pick up practice golf balls (light weight plastic balls) positioned arbitrarily
in a square arena. The robot must store the balls in an onboard bin (once
stored, the balls may not touch the floor of the arena). The arena will contain
up to 20 Table Tennis balls (red, yellow, green and silver). The balls are
positioned in a predefined but undisclosed location inside the arena. Every successfully collected silver ball
earns your team one point. For each collected non-silver ball the team loses ½
point. There will be a maximum time of 3 minutes for the robot to complete the
task. Each team will have two chances at the challenge. The score of the best
run will be counted. The goal of the project is that students will get an
insight into the problems involving:
·
Robust robot design and building (design subject
to constraints)
·
Autonomous navigation (automatic exploration)
·
Programming in NQC (NQC is a C-like language for
the RCX)
·
Sensing and locomotion
·
Dealing with imprecision and real environments
·
Developing team-work skills
Construction Materials
Each team gets the
following material:
·
One Lego Mindstorms Robotic Invention Set.
·
One additional motor (geared, non-geared, or
micro)
·
One infra red (IR) or sonar sensor
·
One rotation sensor
·
Optional: additional sensors and Lego pieces may
be used upon the approval of the instructor.
Each robot should
carry a visible label (or a small flag)
that identifies its creator team’s number
Programming Environment
The
teams are expected to program their robot using NQC. The robots should run in
stand-alone mode (i.e., autonomously). That means that a program for the task
must be downloaded to the robot (in program slot 1) after which the robot is
started (using the remote control). There can be no interaction between the
robot and a computer or remote control while performing the tasks.
The
arena will be a square (painted black) of approximately 4 ft x 4 ft surrounded
by a 3 inch height black walls. No obstacles will be placed in the arena. The
arena will contain up to 20 Table Tennis balls (red, yellow, green and silver).
The balls are positioned in a predefined but undisclosed location inside the
arena.
The
robot starts at the center of the arena, with its front pointing to a
predefined direction. The robot runs will be video taped. Each robot should
carry a small flag that has the team number and name on it (printed in
sufficiently large font size so that the video may identify the robot with its
creator team.)
The robot has to find the silver balls and load them into an onboard storage bin. Every successfully collected silver ball earns your team one point. For each collected non-silver ball the team loses ½ point. There will be a maximum time of 3 minutes for the robot to complete the task.
Next,
the balls are placed back inside the arena, and the robot gets a second chance
to solve the problem; starting at the center of the arena, but pointing in the
opposite direction relative to the first run.
The
winner is the robot with the highest score. Here we take the best of the two
runs.
Additional Rules
The following
additional rules apply:
·
The robots are to stay confined inside the arena
at all times.
·
The robots must work autonomous using a
downloaded NQC program in program slot 1. No outside intervention is allowed,
except for the initial activation of the robot using the remote control device.
·
In all cases, the referee team (made up of the
instructor and TAs) decide and their decision is binding.
·
The kits (including all additional Lego parts,
sensors, motors, connectors, etc.) must be returned to the instructor in a very
good shape and in perfect operating conditions immediately after the
competition. The TA will verify the condition of the kit for each team.
Final Result
Although winning the
challenge is, of course, nice, the project will be judged on other criteria.
Robot originality, simplicity of design, and minimal use of Lego parts and
sensors are desirable features. Each group has to write a report (and post its
electronically on the team’s web page) describing the global solution strategy
chosen (with a motivation why this is the best strategy), the design of the
robot (with a motivation of the design choices), and the NQC program (together
with an explanation of how it works and how particular problems have been dealt
with). Each team should post their report (and any additional material relating
to the final project) on the team’s web page. The final report is due by 5:00
pm (sharp!) the next day after the competition.
Logistics
As mentioned above,
each team will get one Lego Mindstorms set and few additional Lego components.
The team is responsible for returning the complete set immediately after the
competition. The team is responsible for replacement batteries.
The team is expected
to perform the construction and programming on campus, in the lab and/or off
campus.
One test session will
be organized one week before the challenge in which the teams can test whether
their programs work in the actual arena.
The final competition
will take place during the scheduled final exam week or as announced in
advance.