Steer a vehicle with 1 motor by changing the motor rotation direction

[afarber]

Good evening!

In WeDo 2.0 set there is only 1 motor, which can be remotely switched on and off by using the iPad app (by writing a Scratch program).

Also motor rotating direction can be toggled remotely.

As an inexperienced LEGO builder I wonder if it is possible to build a remote-controlled vehicle out of 280 WeDo 2.0 pieces, which would be steered by changing the motor rotation direction.

http://i.stack.imgur.com/jrF3t.jpg

Initially I was thinking of using a caster wheel, which would roll straight when vehicle drives forwards.

And it would snap to a certain angle, when motor rotates in the other direction.

But then I have got a nice advice to use a ratchet instead.

Unfortunately, it doesn't work well. There is too much friction - on the axles of all 3 wheels and on the rubber band:

I wonder if experienced LEGO builders can propose a better vehicle out of WeDo 2.0 parts than mine:

http://i.stack.imgur.com/h7KYk.jpg

http://i.stack.imgur.com/ePo6o.jpg

http://i.stack.imgur.com/kRJKS.jpg

And I feel that my Scratch program for iPad can be improved too, since it is not very responsive to user input (when touching the 4 green arrows):

http://i.stack.imgur.com/ecz1W.jpg

Thank you for any suggestions

Alex

Edited February 23, 2016 by LuxorV
Images too big. Turned into links. Please resize before deeplinking.

[hadidi1999]

So I have an simple trick I found online once that I think could be implemented:

Edited February 23, 2016 by hadidi1999

[hadidi1999]

You might want to try posting this post in the LEGO Technic, Mindstorms & Model Team forum.

Edited February 24, 2016 by hadidi1999

[bonox]

does it have to steer by going forwards, or can you stop and reverse with steer, then drive forwards again? The alternate dune buggy model of the 8479 has a good example of this.