Saturday, March 19, 2016

Slim Margins: A thin combat robot.

Slim Margins is a beetleweight (3 pound) combat robot I made for Motorama 2014. Design goals were:

  • As flat as possible.
  • Disc hubmotor weapon.
It's record is 7 wins, 2 losses at one event before retiring.

Prior to the Event:

Shock mounted drive motors 

Fingertech hubs. I still use them four years later.

Forgot about clearance.

Testing with an old weapon blade.


S7 tool steel.

Such a nice blue temper done in the kitchen oven.

With its derpy brother HAMster ball.

Halfway Through the Event

Burned stator winding insulation. Should not have used the pretty green (and low temperature) wire. The ashes still kept the windings separate so good enough.

Dings and dents.
Chooch on the left.

And chooch on the right.

Blade damage. This one tested at 53 HRc.

Later learned that only six M3 screws are not enough.

Too many screws.

After the Event

Frame tweak

Glamour shot.

Shock mounting strategy worked well.

No electrical problems.

Dat crack.

Noted: make frame as one part.

Rubbing as expected, but no cracked magnets.

The crack prevented the weapon from successfully spinning up in the final match.

Crispy wires.

Screw, banged and mashed.

Evidence of pliers marks where I tried to straighten things.

These work good.

More funny screws.

Stator separation.


YouTube playlist of matches: