1. Cybernetics and Computers
Chapter Lesson 1

2. Cybernetics
Study of how electrical-mechanical devices can duplicate the action of the human body
Comparing the human body to a computer system is an easy way to explain this subject

3. Cybernetics

4. The Nervous System
Uses chemical-electrical signals to control the body
If you touch a sharp needle, nerve cells in your finger “fire” and send a signal through a strand of nerve cells in your hand, up your arm, and into your brain
Nerve cells in your finger are comparable to a sensor, or input device, in a computer system

5. The Brain
Uses billions of cells interconnected by linking cells called neurons
When the brain “thinks”, minute electrical impulses travel from neuron to neuron
Cells in the brain can be either charged (on) or not charged (off)

6. The Brain
By connecting all the brain cells, the brain can decide what to do in each situation
Computers produce logical outputs in a similar fashion

7. The Reflex Action
Specific brain cells are activated by the needle prick (pain) signal, and a reflex output is produced
The brain sends a signal to your arm to pull back
This is similar to the action of an actuator, or output device, in a car’s computer system

8. Computer
Complex electronic device that will produce programmed electrical output signals after receiving specific electrical input signals
Computers monitor and control all major systems of a modern vehicle

9. Computer Advantages
There are several reasons that computers are being used in modern vehicles
Computers can provide several advantages

10. Computer Advantages
Fewer moving parts to wear and go out of calibration
Reduced fuel consumption
Lower emissions
Increased engine power
Reduced vehicle weight

11. Computer Advantages On-board diagnostics Increased driver convenience
Improved passenger safety
Compensation for component wear

12. Binary Numbering System
Uses only two numbers, zero and one
Key to how computers operate
Zero (0) and one (1) can be arranged in different sequences to represent other numbers, letters, words, an input, an output, or a condition

13. Binary Numbering System
To use the binary system, a computer turns switches (transistors) on or off
Off represents zero
On represents one

14. Binary Numbering System

15. Binary Language A single zero or a one is called a bit
Four bits make a nibble
Eight bits make a byte or word

16. Gating Circuits Gate Common gate types:
electronic circuit that produces a specific output voltage for given input voltages
Common gate types:
NOT
AND
NAND OR
NOR

17. “Thinking” with Gates
If an AND gate is compared to two switches wired in series, both switches must be on to activate the starter motor