January 23rd

posted Jan 22, 2017, 9:17 AM by Mr Becker   [ updated Jan 25, 2017, 2:23 PM ]
Those of you that have not submitted your 1st Robotics assignment to me need to get them in........ I'm not going to chase you around.

That said, we will move onto gears.

Gears are in just about everything that has spinning parts. 

 Car engines and transmissions contain lots of gears. If you ever open up a VCR and look inside, you will see it is full of gears. 

Wind-up, grandfather, analog wrist watches and pendulum clocks contain plenty of gears, especially if they have bells or chimes.

Gears are everywhere where there are engines and motors producing rotational motion.

Gears are generally used for one of four different reasons:

  1. To reverse the direction of rotation
  2. To increase or decrease the speed of rotation
  3. To move rotational motion to a different axis
  4. To keep the rotation of two axis synchronized
Gears come in many shapes and configurations.  Lets take a look at some of the more common types.   


Here is a fairly long video that goes into  greater detail

Gear Types and characteristics ‎[360p]‎.mp4

Gears and Gear Ratios

In mechanical engineering, a gear ratio is a direct measure of the ratio of the rotational speeds of two or more interlocking gears.
As a general rule, when dealing with two gears, if the drive gear (the one directly receiving rotational force from the engine, motor, etc.) is bigger than the driven gear, the latter will turn more quickly, and vice versa.

Here is a breakdown from NC State Engineering School in Havelock, which explains this concept and how different configurations give you different results.  Try the problem at the bottom, and see how you do.   

Below are some simulations you can play around with to get a better feel for gears and gear ratios.

Try building this Simple Gear with the Fischer Technik set
Simple Gear Exercise

When you get it, move on to the Gearbox in Fischer Technik booklet. (page 25 of the color booklet)