1. CONTROL TECHNOLOGY
Lesson Four: Decision Tables

2. LESSON AIMS
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that
controls a simulated environment.
• SOME: Explain the advantages of computer
control over human.

3. EXAMPLE OF A STREET LIGHT FLOWCHART:
Start
Switch output 3
YES on
Is light less than 50?
NO
Switch output 3
off
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

4. DECISION TABLES
A decision table is used to make it clear what
the different options are for a system that has
sensors:
Purpose of the system: open the door when people are present
Device
What the sensor says? Automatic Door
Person near Door Open
N o person near Door Close
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

5. GREEN HOUSE MIMIC
AUTOMATIC SYSTEMS
Can you work
out what are the
different inputs
and outputs in
this mimic?
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

6. GREEN HOUSE MIMIC:
AUTOMATIC SYSTEMS:
Inputs: Outputs:
Moisture Heater
Temp Light
Sun Window
Sprinkler
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

7. GREEN HOUSE MIMIC:
DECISION TABLES:
If the value of the sun is greater than 20;
the what should happen to the sprinkler
output?
Purpose of the system: Water the pants if too hot
Device
What the sensor says? Sprinkler
Light Level > 20 ON OFF DO NOTHING
Light Level < 20 ON OFF DO NOTHING
• ALL: Know what a decision table is.
Remember:
• MOST: Produce a Flowol program that controls a simulated environment.
> means more than
• SOME: Explain the advantages of computer control over human.
< means less than

8. GREENHOUSE MIMIC
Now go on to Flowol and open up
the greenhouse mimic; can you
work out how to create a program to
make it run?
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

9. GREENHOUSE MIMIC:
COMPLETED
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.

10. PLENARY
After completing this flowchart; what
are the advantages of using a
computer controlled system? Discuss
in pairs.
HOMEWORK
What would be the advantage of
using a human to control the
system?
• ALL: Know what a decision table is.
• MOST: Produce a Flowol program that controls a simulated environment.
• SOME: Explain the advantages of computer control over human.