Build Your Own Robot Lego Mindstorms is a Lego kit that contains many of the usual Lego parts plus a

Build Your Own Robot

Lego Mindstorms is a Lego kit that contains many of the
usual Lego parts plus a programmable brick, a series of sensors and some
motors. The sensors include buttons, microphones and ultrasonic sensors that
can detect objects at a distance. The kit can be used to create a wide variety
of robots including a Rubik’s Cube solver, a miniature car factory and a
robotic puppy. It is also an excellent way to learn computer programming. Programming
involves taking a problem and breaking it up into tiny steps, then assembling
those steps into code that will solve the problem.
View complete question »

Build Your Own Robot

Lego Mindstorms is a Lego kit that contains many of the
usual Lego parts plus a programmable brick, a series of sensors and some
motors. The sensors include buttons, microphones and ultrasonic sensors that
can detect objects at a distance. The kit can be used to create a wide variety
of robots including a Rubik’s Cube solver, a miniature car factory and a
robotic puppy. It is also an excellent way to learn computer programming. Programming
involves taking a problem and breaking it up into tiny steps, then assembling
those steps into code that will solve the problem. The steps can be made to run
one after another, or a set of them can be made to repeat over and over again.
At certain points a choice can be made to do one of an unlimited set of steps
according to a condition. This gives us the following three ways to assemble
the steps: (1) a sequence of steps, (2) loops of steps and (3) selection of
different steps. Let’s see how we can break down getting a robot to navigate a
maze into a series of steps. Let’s say we’ve built the robot already. It’s got
wheels and a motor to move about and can make turns. To make things easier,
let’s say it can turn exactly 90 degrees in either direction and that the maze
is made up of walls that can be detected by an ultrasonic sensor attached to
the robot. The maze walls are made out of units of the same length and only
contain 90 degree corners.

How could we break up navigating a maze? In fact, the only
steps we need are: move forward one unit, look ahead, turn left and turn right.
Imagine the steps involved in making just one move. The robot looks ahead. If
the route is clear it moves forward. If there is a wall ahead it turns left and
looks ahead in the new direction. When it looks ahead, if the route is clear it
moves forward. If there is a wall ahead it turns right twice (once to return to
its original position, and once to turn to face right). If the route is clear,
it moves forward. If the route is not clear, it turns right again (so it’s now
facing backwards from its original position). If the route is clear, it moves
forward. That’s basically one move. All the robot has to do is repeat all of
that until it finds the centre of the maze or the way out. Here’s what it looks
like written out as computer instructions:

There’s a lot of statements that say ‘if route ahead clear
then move forward’ in this code and one of the questions below asks if you can
re-write it to remove some or even all but one of them. Also, ‘route ahead
clear’ is not precise enough and needs to be re-written in terms of the
ultrasonic sensor, something like: ‘if ultrasonic(10 cm) = FALSE’, which says
‘if the ultrasonic sensor doesn’t detect an object at 10 centimetres’. Also the
code should really start with something like: ‘Repeat until out of maze’. If
you don’t want to invest in a Mindstorms kit in order to learn computer
programming, perhaps you can try the Hour of Code instead. You can access it
from: https://code.org/learn.

Questions

1. Re-write the code to remove some or all but one of the
statements that say: ‘If route ahead clear, Move forward’.

2. Mindstorms and the Hour of Code are aimed at secondary
school children (but don’t let that put you off giving them a go). Do you think
it is important for children to learn to computer program?

3. Write some code like that shown in the case to sort a
list of words into alphabetical order.

4. Can you think of a robot project that would inspire
undergraduate students studying information systems?

View less »