Basic Robot Mechanics

1
Basic Robot Mechanics

• TED 384
• Computer Applications in Industry (Robotics
  Education)

2
Basic Mechanics

• Simple Machines
• Lever
• Inclined Plane
• Wedge
• Screw
• Wheel and Axle
• Pulley

http//www.csmate.colostate.edu/cltw/cohortpages/v
iney/oriole.html
3
Simple Machines

• Lever
• Downward motion at one end results in upward
  motion at the other end.
• Depending on where the pivot point is located, a
  lever can multiply either the force applied or
  the distance over which the force is applied

http//www.csmate.colostate.edu/cltw/cohortpages/v
iney/balance.html
4
Simple Machines

• Inclined Plane
• Sloping surface used to lift heavy loads with
  less effort

http//www.sirinet.net/jgjohnso/simple.html
5
Simple Machines

• Wedge
• Converts motion in one direction into a
  splitting motion that acts at right angles to the
  blade
• A lifting machine may use a wedge to get under a
  load

http//www.mos.org/sln/Leonardo/InventorsToolbox.h
tml
6
Simple Machines

• Screw
• Converts a rotary motion into a forward or
  backward motion

http//www.sirinet.net/jgjohnso/simple.html
7
Simple Machines

• Wheel and axle
• The wheel is locked to a central axle so that
  when one is turned the other must turn
• Longer motion at the edge of the wheel is
  converted to a shorter more powerful motion at
  the axle and vice versa

http//www.sirinet.net/jgjohnso/simple.html
8
Simple Machines

• Pulley
• Reverses the direction of force
• Two or more pulleys connected together permit a
  heavy load to be lifted with less force

http//www.sciencemuseum.org.uk/on-line/leonardo/I
nventorsToolbox.asp
9
Remember Motors?

• Motors convert electrical energy to mechanical
  energy.
• Mechanical energy moves our robot
• Motors drive the gears

http//www2.towerhobbies.com/cgi-bin/wti0001p?IL
R9520PDS
10
Basic Mechanics

• Gears
• Spur
• Flat
• Pinion
• Bevel
• Crown
• Worm
• Rack and Pinion
• Differential

www.mathworks.com
11
Gears

• Spur Gears
• Straight teeth mounted on parallel shafts
• Many used at once to create very large gear
  reductions
• Flat
• Pinion

http//en.wikipedia.org/wiki/GearWorm_gear
12
Gears

• Bevel Gears
• Gears that mesh at an angle, usually 90
• Changes the direction of rotation

http//science.howstuffworks.com/gear4.htm
13
Gears

• Crown Gears
• Special form of bevel gear
• Has right angles to the plane of the wheel

http//www.plastic-gear-manufacturer.com/industria
l-gear.htm
14
Gears

• Worm Gears
• Changes the direction of turning motion by 90
• Decreases the speed of turning from screw to gear
  and increases the force

http//blogs.toolbarn.com/brianm/labels/Tool20Inn
er20Workings.html
15
Gears

• Rack and Pinion
• Converts rotary motion to back and forth motion

http//en.wikipedia.org/wiki/GearWorm_gear
16
Gears

• Differential
• Splits torque two ways, allowing each output to
  spin at a different speed

http//nxtasy.org/wp-content/uploads/2006/08/Diffe
rential2-00.html
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Gears

• Gear Assemblies
• LEGO Technic 1031 Gear Assembly Activity
• Gearing up and Gearing down

http//reprap.blogspot.com/2005_12_01_archive.html

18
Cool Site

• http//nxtasy.org/
• Includes plans!
• NXT Aerial Ropeway
• NXT Gymnast
• NXTWay-G Balancing with a Gyro Sensor