pic: Differential Swerve (Close Up View) with Advanced Gear Kit

A close up view of a robot our team built to demonstrate the differential in the new Advanced Gear Kit. The robot turns extremely well and can turn and drive at the same time with no skidding. This robot will be available for anyone to drive at Monty Madness.

That differential looks almost identical to the LEGO ones. Is it fairly easy to assemble? I know I’ve always had a heck of a time getting the LEGO ones together

I remember when I assembled my first lego differential based vechicle… :rolleyes: It made me crazy to put it together but jeesh was i happy when it was! I’ll have to get my hands on one of these, always have been facinated by differentials.

Great job on the assembly! :wink:


Hmm, this was my weak point when working on the race car back in high school – I was more of an engine & electronics guy. What is the point of a differential for those of us who can’t visualise why you’d want 2 wheels turning in opposite directions on the chassis setup you have for this particular bot?

In the differential in a car, the wheels do NOT normally turn in different directions; (although it is possible) rather they turn at different speeds. When you drive around a corner, the outside wheel has to turn faster (bigger radius circle), and the inside wheel has to turn slower (smaller radius).

The way this is achieved is that the entire body of the differential can spin, causing one of the output shafts to spin slower that the other. (It’s kind of hard to explain in words, these links may be of some help: :wink:

I’ve used differentials like this for various applications, usually when I need an output shaft to be able to switch from rotating with the input to rotating opposite. This can be done by allowing the entire differential casing (as shown here) to rotate, or by locking it up.

Is the differential the only thing that comes in the “Advanced gear kit”? Does it come as one unit, or does it have to be assembled? I assume the bevel gears could be used for other applications?

The kit comes with the differential frame, bevel gears (which can be used in the differential or for other applications), rack gears and worm gears (plus a few spur gears to use with the worm and rack gears).

You can see the contents here: http://www.vexlabs.com/vex-robotics-advanced-gear-kit.shtml

I should get those so I can build a coaxial crab…

Looks sweet.