Control Module

1
Control Module

• Past paper questions
• (Higher Tier)

2
Central Heating System
Sample 2003 10
Maintain the temperature between 170C and 230C
Input Sensor
Output device(s)
If temperature lt 17 then switch on heater and
switch off fan If temperature gt 23 then switch
off heater and switch on fan If temperature is
between 17 and 23 then do nothing
3
Greenhouse
2000 8b
Bring the temperature up to 220C and keep it
there (using only a thermostat and a heater)
Input Sensor
Output device(s)
If temperature lt 22 then switch on heater If
temperature gt 22 then switch off heater If
temperature 22 then do nothing
4
Car Wash - 1
1999 10
Tokens Bronzewash only, Silverwashwax,
Goldwashwaxdry
Output device(s)
Input Sensor
5
Car wash - 2
1999 10

• Traffic light (outside) set to red
• Token placed into coin slot
• Colour detector sensors colour and sets the type
  of wash
• Nothing happens if the pressure pad (inside) is
  on
• When pressure pad inside car wash is off then the
  traffic lights (outside) are set to green
• Pressure pad (inside) detects new car is in
  position
• Traffic lights (inside and outside) set to red
• Infra red beams (or similar sensor) detects width
  of car

6
Car Wash - 3
1999 10

• Wash program starts, depending upon colour of
  token
• The following happens when the wash finishes
• Traffic light (inside) set to green
• Car exits the car wash
• Pressure pad (outside) detects that car has left
  the car wash
• Whole process can now be repeated

7
White Line Following
1998 6a
How can the robot follow a white line around the
warehouse
Input Sensor
Output device
Light is shone onto the floor White line reflects
more light than the rest of the floor Using two
LDRs will allow calculation of where robot is
8
Burglar Alarm - 1
Explain how a burglar alarm system works
Input Sensor
Output device
If the burglar alarm detects/senses an intruder
via an input The appropriate output will be
switched on (various similar answers)
9
Car Park Barrier - 1
Explain how computer control is used at a car
park entrance
Input Sensor
Output device
10
Car Park Barrier - 2

• Pressure pad (outside) senses that a car is
  waiting
• If the car park is full then nothing happens
• If the car park is not full, then the following
  happens
• A ticket is partially ejected (probably using a
  motor)
• The ticket sensor can detect that a ticket has
  been taken
• Car park barrier is raised (using a motor)
• Pressure pad (inside) detects that the car is in
  the car park
• Barrier is lowered (using a motor)
• Counter is increased by 1. If car park full then
  full light is put on