Spider_robot

[MichaelWareman]

Hello:

I need some help with the Spider_robot. You can find the LXF file on rebrickable.com -- https://rebrickable.com/mocs/MOC-13710/ArtHsgw.jp/spider_robot/?inventory=1#comments

I think the problem is the orientation of the 4 pairs of legs when I built each pair. Any help would be greatly appreciated.

Mike,

[MichaelWareman]

I now have a working spider robot. The required orientation is to have one leg in the up orientation and the other leg in the down orientation. To do this required me to pull the axle pin holding the small gear so that the two larger gears could be turned freely. By turning the larger gears so that round pin holes are oriented vertically I was able to have one leg up and one leg down for each pair. For convenience I choose to have the front leg (when seen from the front) of each pair be in the up position. I opened up the legs so that the picture better shows the up-down orientation. Hope this helps anyone else interested in building the amazing robot. 
 

So now the next step is to program the spider robot. The easiest movement is simply to run each motor in a forward direction. Note that one side the motors run clockwise while on the other side run in a counter clockwise direction. By varying which motor runs clockwise and which runs counter clockwise it is possible to make the robot move forward, backwards, turn left or right, and even move sideways!  Any ideas on how to get all the legs in the same up-down orientation. There is not a lot of room for touch sensors so I was hoping to use the motors themselves as a way to synchronize all the motors to the same orientation as an initial setup, maybe even as a continuous running or the motors. I was looking at Anton’s notes on synchronizing two motors https://www.antonsmindstorms.com/2019/01/24/how-to-program-two-synchronised-ev3-motors/ Unfortunately the motor needs to turn 1080 degrees (this figure comes from the original program code) for the large gears to do one rotation - 360 degrees. Still playing with this part. Any help or thoughts would be greatly appreciated. 
 

Another programming challenge is how to setup the three ultrasonic sensors to coordinate the robot’s movements. Again, any help or thoughts on what needs to be done would be greatly appreciated. 

Mike

[Coder Shah]

You might want to try posting on the EV3 facebook page:

https://www.facebook.com/groups/legomindstorms/