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Unread 15-03-2015, 14:04
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Re: Al's Annual Inspection Thread 2015

Quote:
Originally Posted by Thad House View Post
I get the zip tie thing, but at the same time I don't. The field is held together with zip ties and Velcro, and it seems to work just fine. As long as you buy good quality zipties, they could easily hold a robot together.
The only parts being held together on the field by zip ties are the Lexan covers (NOT structural, these are intended for shielding and to provide a smooth playing surface). In those cases, the physics are well understood - most of the force against those covers will come from head-on collisions with robots, in which case they are pushed against the pipes supporting them. Sliding force has been known to break zip ties on the field, and they are replaced as needed. Additionally, if those zip ties break and the Lexan comes lose, it's not exactly moving - it just flops to the ground. The structural elements to the field (all the aluminum piping) is held together by slotting pieces inside of each other and locking them in place with pins. There is a firm mechanical joint between every part of the field structure, and it's designed so it can only come apart in a very specific way.

Contrast that to a weight attached to a robot. The weight is constantly experiencing acceleration and deceleration as the robot moves around. It can take an impact from another robot, in which case this is two robots hitting each other, not one robot hitting a stationary target. If the robot is spinning in a circle full speed when the zip tie lets go, the weight isn't just going to fall to the floor - it's going to be thrown across the field (and possibly outside of it). This is a much more dangerous situation.
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