Interactive Primary Newsletter 29 Technological Magic, Ears & Roamer

Ever let the fancy roam3 What has all this waffle about ears and sound waves to do with controllers? The answer is, of course, electricity. Electricity is an easy form of energy to control. Think of a light switch at home or, for more sophistication, a switch at a pedestrian crossing. In the previous exercise, it was explained that, in humans, electrical signals are sent to the brain and muscles to produce movement. Using similar electrical signals, we can do the same with Roamer but in this case the electrical signals will be sent to an electric motor. If a Roamer is told where to go and what to do it will ‘remember’ these instructions. When Roamers’ switches are pushed, electrical signals are sent to its ‘brain’. If they are input in the correct order the instructions will be carried out. Imagine Roamer is going into a burning school to search the classrooms. How can it be asked to look in all the classrooms? To do this, Roamer must be given a set of instructions called a program. When writing programs remember that the computer carries out your instructions as you write them - first instruction, first action. The Roamer instruction booklet is easy to follow and is an excellent introduction for those approaching this type of programming for the first time.   A simple diagram drawn on a roll of surplus wallpaper can be used to simulate a ‘burning school’ to test out a Fire Rescue program, see Figure 7 opposite. Figure 7 Fire rescue template on scrap wallpaper   The part program shown in Figure 8 below, is one way of instructing Roamer to inspect each room - but what will this achieve? Is the robot equipped to be of any help in this situation? Figure 8 Start of program to search rooms One look at Roamer is all that is needed to generate a debate on this. How can the robot see, hear or help anyone trapped by the fire? What could be added to Roamer to make it more useful? Well, amongst other things, Roamer could be given a microphone/speaker for communication, a camera to provide ‘vision’, a fire extinguisher to fight the fire and a buggy to pull survivors from the flames. Whatever happens remember - DON’T PANIC4 this is a box containing passive electronic components powered by a low voltage battery, difficult to cause any serious damage. Supply details Rapid Electronics - Roamer batteries Severalls Lane Colchester Essex CO4 5IS Tel. 01206 751166 Part Number PJ996/4R25 Available from SSERC (members only) - 4mm to 2mm reducers pack of 5 @ 25p - item 867 Ceramic magnet 12p each - item 823 3 Keats Fancy 4 Douglas Adams The Hitchhiker’s Guide to the Galaxy