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Robotic arm tank Challenge: high obstacle

Navigate around commanded by phone or autonomous. Can overcome obstacles higher than the tracks

We create robots that sometimes move around but, what happend when those robots find an obstacle?

If the obstacle is small the robot can pass over it, with a tracked robot is not very difficult, unless the obstacle is higher than the top of the tracks. Then usually the robot can't overcome the obstacle... until now.

With this solution (it's not new but it is with this robot), you can see the the robot that overcomes an obstacle that is twice the high of its tracks. How? Using leverage.

Behind the arm there are two bars and at the end two free wheels (not powered), in order to leverage the robot. It's better to see it in the video attached.

Here you have a gerenal view of the solution I made:

General view of the extension and robot

 

Here is a detail of the solution:

Details of the solution

 

Here the wheels:

Details of the wheels

 

And here the connection of the bars to the arm of the robot:

Details of the attachment between the bars of the extension and the arm

 

Please note:

So, what do you think about this solution.

I'm planning already new experiments with this robot. Any suggestions or questions are welcome. Thanks!

 

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Have you tried it on stairs?

I believe it's not designed to climb stairs, in case there's a single obstacle as we see in video, it's working.

 

Yes Sw0rdm4n you're right. This robot is designed only for an obstacle at a time.

 

Hi Hoggernick,

Thanks for the question, but this robot is not designed for stairs, just one obstable at a time. I though about stairs but it will requiered a substantial change of the robot, which maybe I do one day ;-)

I really like the idea of expanding tracked robots to tackle tall obstacles. I've tried one like you've built here using the Dagu Rover platform and an arm that's operated by a servo, but the servo wasn't strong enough. You've definitely overcome that issue with the gearing and motor. Did you put endstops on it so that it won't try to overextend? I'd really like to build one like that that can also climb stairs. That's a really tough challenge.

 

Hi Hoggernick, the track motors of this robot are powerful enough, also the extension of the arm to the back is long enough to leverage it. However it's at the limit: with batteries at mid capacity or more weight the robot can't overcome tall obstacles.

I don't use endstops but gyro sensor, so I detect the actual position. I check it against the maximum and minimum positions I know it can realize. Then the robot changes the position via a PID made on scratch ;-)

Stairs are very tempting but is a challenge much more difficult: you need more power, extended actuation surface (more tracks) and more power. Definitely it's possible but with more resources...