Re: NXT Synchro Drive

On Dec 7, 2006, at 1:48 PM, Chris Phillips wrote:

> In lugnet.robotics, Rich Thompson wrote:
>> On Dec 7, 2006, at 7:03 AM, Chris Phillips wrote:
>>
>>> In lugnet.robotics, Rich Thompson wrote:
>>>> I have been playing with the turntable from the NXT kit to try and
>>>> build a synchro drive train. It got a bit complicated but it  
>>>> works. I
>>>> posted a video at my blog:
>>>>
>>>> <http://www.robotthoughts.com/index.php/lego/archives/2006/12/06/
>>>> lego-mindstorms-nxt-synchro-drive/>
>>>>
>>>> or just:
>>>>
>>>> <http://www.robotthoughts.com/>
>>>>
>>>> Have Fun!
>>>
>>> This looks pretty cool, and I can well respect any attempt to
>>> design a cool
>>> device out of LEGO, but I wonder how necessary something like this
>>> is with the
>>> NXT?
>>>
>>> Just wondering...
>>
>>
>> You are touching on the exact reason I am playing with the synchro
>> drive platform. Previously, to maintain "sync" between the rotation
>> of different wheels I had to use locked gearing or a chain. you can
>> see examples here:
>>
>> http://www.robotthoughts.com/index.php/lego/archives/2000/07/20/ 
>> astro-
>> droid-synchro-drive/
>>
>> and here:
>>
>> http://www.robotthoughts.com/index.php/lego/archives/2000/07/20/
>> synchro-drive-with-360-degree-bumper/
>>
>> By working with NXT motors, I hope to not have that design  
>> requirement.
>
> Yes, I think the new capabilities of the NXT are going to give us  
> all a new
> perspective on the challenges we've taken on in the past.
>
>> As to why this platform, I like the zero degree turn radius and the
>> design is fun to watch when the full synchro drive is in motion. See
>> the videos in the robots above. Once you understand the synchro
>> drive, it really opens up some of the robotic possibilities of the
>> turntable.
>
> Cool!  There are other benefits to synchro drive as well, I  
> suppose, such as the
> ability to change direction without changing the orientation of the  
> chassis.
> It's always good to see someone continuing to push the envelope.
>
> You're probably already aware of these other designs, but I'll add  
> the links
> here for (my own) future reference:
>
> http://www.restena.lu/convict/Jeunes/SynchroDrive.htm
> http://www.visi.com/~dc/synchro/index.htm
>
> By the way, your synchro drive page is already the #3 result on  
> google!
>

Good links! I love those original synchro drive sites. They inspired  
me originally and looking at them again reminds me of a few ideas I  
have let slide from my brain.

At the risk of this looking like link pimpage, I offered one  
improvement on those original designs to increase the strength of the  
wheel rotation gears. You can see that improvement here:

http://www.robotthoughts.com/index.php/lego/archives/2001/03/20/ 
stronger-synchro-drive/

Crazily enough, my blog is so old and linked to that many posts on  
less important keywords go right to the top.

I am getting back into the robotics side after a few years of just  
noodling around with my original RCX sets without much impact. The  
NXT has re-energized me a bit but I'll need to get rid of this pesky  
need for money soon :)

Have Fun!

Rich