Firky2010

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LEGO Facts

  • LEGO is an abbreviation of the two Danish words "leg godt", meaning "play well"
  • During the moulding process, the plastic is heated to 232°C until its consistency is that of dough
  • In 2003 LEGO  changed the minifigure's yellow facial colouring to a more authentic skin colour
  • In 2006 the LEGO  website had an average of 8,137,062 individual visitors a month
  • If you built a column of about 40,000,000,000 LEGO bricks, it would reach the moon

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845days since
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Lightweight Forearm


My main goal with the forearm is to provide a good solid base for the wrist, but this cannot be too heavy, otherwise I would not be able to construct anything able to lift or lower the arm. The Forearm has to house the motors that control the 360 degree wrist - in my case thats one XL motor and one M motor.

 
This above design was over 2 foot long and over the length of this arm there was an unexceptable amount of flex so I set out to improve my design. I started by shortening the forearm. I then added the battery box - this gave the forearm some counter balance. But the design below weighed over 850 grams. This was way too heavy to work with, and also very wide. It was a mammoth task to make the elbow and it just looked ugly. On the plus side this design was self contained with its own battery box and IR receivers.


So again I set to work to improve my design. This Arm went on a diet and now weighs only 600 grams, plus it uses 2 XL motors instead of 1 M motor and 1 XL. This gives the wrist much more lifting power and strength. The gearbox also runs smoother and takes up less space, also resulting in no jumping or slipping gears. Finally the slim design is going to make it much easier to build an elbow.


This is a new design this design includes an XL motor for the elbow which helps reduce the size of the upper Arm. This design using the least amount of gears as possible to prevent any gears from jumping and to take up the least amount of space.