Switches

Question 1

What is a Switch?

Answer 1

• open and close a circuit

- can be used to adapt everyday objects to allow someone with a physical limitation to use the object

Question 2

most common sites in order to place switches

Answer 2

1. hands- horizontally or vertically
2. head-either side of head
3. mouth-sip n puff or tongue activated
4. feet- doors flexion, plantar flexion or lateral movement
5. other UE locations
6. other LE locations
7. mind

Question 3

types of switches

Answer 3

mechanical and electrical

Question 4

mechanical switches

Answer 4

most common
require physical depression over a short distance for activation and release, varying amount of force are required for activation

Question 5

electrical switches

Answer 5

require a power source, no physical depression or force is needed for activation

Question 6

modes of switch operation

Answer 6

1. momentary (continuous): maintain pressure on switch to keep it working
2. latched: activation turns it one reactivation turns it off
3. timed: activation turns on and runs for specific time
4. switch-latch timers

Question 7

mechanical switch types

Answer 7

plate:flat surface which is depressed to activate switch
light touch plate: same as above but requires less pressure to activate
lever: bent in any direction to activate
pneumatic: change is air pressure to activate switch (sip and puff)
mercury: tipping the switch allows a drop of mercury to activate switch

Question 8

wireless/remote switches

Answer 8

mechanical switches that are wireless

Question 9

electronic switch types

Answer 9

proximity: activated by a body part coming within an adjustable range.

fiberoptic (visible light): breaking the beam of light activates the switch

infrared (invisible light): breaking the beam of light activities the switch, designed for larger movements

touch: the skin is conductive and completes circuit to activate the switch
sensor: pick up electrical impulses from the muscle to activate the switch

photocell/photoelectric: same as fiberoptic but range up to 21 inches

sound activated: volume of sound activates switch
piezo electric film: vibration

ultrasonic: invisible light ranges from 6 inch to 30 inches

mind switch (bioelectrical): combination of muscle 
movement and EEG readings. worn on the forehead