Design & Technology
Form 1
Project : One gearbox - four legged - robot
Situation :
We want an animal or a pet.
Design Brief : Can we make a mechanical or robotic animal ?
Design Specification :
 It can stand up on 4 legs.
 It can walk with 4 legs in a straight line.
 It can move its head or ear or tail.
Research :
 Research on terms like equilibrium , center of gravity , base area ,
moment & stability. (‘www.bbc.co.uk/education )
 Research on Form & Shape of four legged – walking – animal.
(Search engine : ‘www.hotbot.lycos.com )
Research on electronics :
voltage & current
(‘www.dtonline.org )
circuit,
Sketch :
 At least one sketch on form & shape : 4- legged-animal.
 At least one sketch on mechanisms ( i.e. lever & linkage , screw &
nut, washer/ wheel ) with a circuit diagram to show current flow in
the robot.
Explorations :
One comparison table ( with text & graphics by “WORD” ) to show
various material properties.
Solutions :
 One final drawing on 4 legged animal with wood color. ( label :
materials , size ) & with mechanisms. ( label : gear combination ,
crank , lever & linkage , screw & nut, washer/ wheel , friction )
 Comic drawing to show the movements of 4 legs, head or ear or tail.
Sample 1 : Comparison Table ( Word )
Grade : *slightly
Products
*moderately
materials
Soft/ Light/ Rough/ comments
hard heavy smooth
teak
***
http://www.solidteak.
com/louis/louis.htm
Pine wood
http://www.logbeds.c
om/products.html
Aluminium
http://www.world-alumin
ium.org/
Copper
http://www.copper.or
g/mechanical/homepa
*strongly
**
**
Too heavy for making
robot
ge.htm
Acrylics
http://www.customacr
ylic.com/
Styrofoam
http://www.foamprod
uct.com/
Carton paper
http://www.smpaperb
ox.com/products.htm
Sample 2 : sketch on form & shape : 4- legged-animal
ear
horn
eye
nose
tail
Paper card
rope
short legs
A cow
Sample 3 : mechanisms with a circuit diagram
Motor
Battery ( AA size)
current
Sample 4 : Comic drawing
Sample research on 4 legged animal
Form & Shape
internet research graphics ( or newspaper cutting or magazine cutting )
head
eye
nose
ear
tongue
tail
legs
http://www.petnet.com.au/dogs/dogbreedindex.htmlCocker Spaniel
(American)
He is a smaller dog, less heavy, with luxuriant coat and a distinctive chiseled
head. Developed in the United States to hunt
British Bulldog
Dalmatian
a cow
http://www.cyg.net/~ljordan/pictures.html
Locate & label parts of the animal :
Head
x
neck
leg
x
eye
x
mouth
shoulder
arm
foot
tail
x
x
nose
ear
hand
hip
x
belly
Workshop Evaluations :
( cross ‘x’ if the problem happened to you )
1. Asymmetrical : left hand side length of motor shaft different from right
(
2. Asymmetrical : motor shaft not horizontal
(
3. Asymmetrical : length of left leg different from right leg
(
4. Asymmetrical : length of linkage at left different from right
(
5. Friction : robot hits the wall of track & stops
(
)
)
)
)
)
6.
7.
8.
9.
10.
11.
12.
13.
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Friction : robot steps on the same location
Friction : robot walks in a curve
Friction : screw & nut too tight
Friction : Linkage arms too tight to move
Friction : Linkage arms rub / kick each other & stop
Center of gravity : Legs too long
Center of gravity : too high & robot falls
Base Area : too small & robot falls
(
(
(
(
(
(
(
(
14. Base Area : foot too big
(
)
15. Misalignment : motor shaft out of crank
16. Electrical circuit : copper wire is in contact with motor loosely
(
(
)
)
Phase
one
two
three
four
five
six
task
research & sketch
lever & linkage
form & shape
circuit & walk in balance ( 7 ft. track )
competition
report & evaluation
no. of cycle
3
3
2
2
1
1
total
12