Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

1) Cans, totes, robots, people, etc. Two motors are dedicated to the 'pinching' function, the other two power the rollers on the pincher.
2) Nope. We've done a fair amount of control theory work and implementation this year. It's been a great experience for our students to be exposed to even more practices that are fairly common in the controls industry.

All of our rezeroing, minimum and maximum positions are determined by using a combination of position gathered using a quadrature encoder and monitoring output current and output voltage.

For example, we'd limit the upper end of our elevator travel based on an estimated position and then we'd calculate how much power is going into the elevator to prevent a motor stall condition.

After profiling the current draw, we determined that it requires a little bit of logic to figure out if we're indeed stalling the gearbox, or lifting a bunch of totes.

We'd also rezero our elevator when it returns to its minimum position. Essentially, we'd allow for the elevator to run past the minimum position. Once we've detected that we're not moving anymore, the position is past the minimum position (our elevator has a spring loaded return cable), and current has trended upward, we can safely say that we're at the minimum position. We'd then allow the elevator to back drive itself via the spring to its natural state where we'd then reset the encoder.

Finally, we're using a quad encoder on our pincher gearbox along with two different PIDs. One PID handles position control so that our drivers can quickly acquire game pieces. Once the game piece is kinda-sorta in our possession, we'd switch to a current based PID.

This ensures that we'd be placing almost an equal amount of force on what ever we decide to grab. This configuration works on game pieces in any orientation. Cans fallen over, Cans upside down, totes from the wide side, totes from the long side, totes that are upside down, you name it.

3) We do not powdercoat our stock and do post machining. It just happened to be on that part, we kind of forgot a few holes. Careful measurements and some patience later along with a handheld drill, we'd have some pretty precise holes.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

Are the rollers on the "pincer" polyurethane tubing like McMaster carries?

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

Maybe :)

We took them off for the photo shoot. They look a bit funny to us.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

I just have to say, this is the coolest looking robot I have seen for this competition. The Holy Cows never fail to impress me with their amazing powder coating. Well done.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

Excellent Bot saw it up close and personal. So glad to see THE CLAW working on final bot! Their wire management is crazy good.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

That wiring job is so sexy I would date it.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

This is the most beautiful robot I've seen this year. Look at those curves, those edges, that wiring, the sponsor plates...holy cow.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

What a beautiful Robot, I can't wait to compete with this at SDR.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

Impressive, intimidating, and (most importantly) inspiring...as always! I'm looking forward to seeing you play in Arizona and then seeing it for myself in San Diego.

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

As always, a gorgeous robot with incredible wiring. What kind of connectors are those coming off of the talons? What are the advantages of them compared to Andersons?

Re: Team 1538 / The Holy Cows - 2015 Robot: Daisy Quickstep
 

Those connectors are Deans Ultra connectors. We mainly chose them for the form factor. Also, the plug, including the solder joints, have less resistance than a piece of 12 awg wire of an equivalent length.