Drone

Can some one make a drone bot? Its possible, Power is gonna be insane but an L3 hab climb could be possible!

Are you sure about that one?

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You’d have to do it using legal motors (775Pro or Redline, most likely), the legal battery, the legal control system, and it’d have to have legal bumpers.

That last part is what’ll probably ground that idea.

OHHH forgot about the legal motor rule :neutral_face:

Rough math.

Standard rule of thumb is 75 Watts per pound on a multirotor. The battery is 15 pounds. That’ll require 1125W to keep in the air. Which is ~4X 775pros at Max power.

PDP, VRM, roboRIO, Radio weigh around 4.5-5lbs. that’s a 5th 775pro.

Now you need motor controllers to power these. 5 talonSRXs is another pound. Add this to the weight of the motors and you need a 6th motor. This isn’t including wires. That’ll probably take you to 8. Add in an actual frame, say 15lbs (it’ll be heavier than that though), that’ll take you to 12.

Now you have 4 PDP slots left for mechanisms. Choose wisely. Any added weight will mean you need more motors for lift. And I didn’t even account for the weight of bumpers…

Oh yeah, running 12x 775pros at max power (12V @ 85A ish) will draw 1020 amps through your main breaker. Have fun with that. Realistically you won’t get off the the ground because your battery voltage will sag to oblivion and your main breaker will pop pretty quickly. Even if my math is off by a bit, I think the point still stands.

TL;DR wouldn’t recommend

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@Sriram_Neravati in another thread you mentioned “proving” that you could make a 120lb drone, did you have rough calculations to back that up?

I have a friend that makes heavy drones. I only fly lightweight racing. I reposted this because I didn’t account for the motors that were allowed. Also they work pretty much only with LiPo batts.

Tl;dr: there’s a ton of challenges with getting this done even outside of the frc motor constraints

You would also need a way to stay within your bumper zone while going around on the field meaning you would need a frame with bumpers on it to begin with. In order for you not to extend 30 inches outside while trying to score this frame would have to move around with the drone. Assuming you want to not only do level 1 you couldn’t drag it using the drone because if the cable was long enough to reach up to level 3 it would be impossible to drag that along while not near its max height. This means you would need to have some spooling system for the cable on the robot. However another problem arises. Another robot can play defense on you or your alliance partner can bump you which will cause your chassis with the bumpers on it to move causing your drone to extend past 30 inches. At this point you would need a drone, a cable, and some sort of a chassis with your battery, some electronics on it, and a spool. If you wanted to climb up onto level 3 having to carry all that weight even if you had the ideal non-frc legal motor would probably be impossible to do in under the weight limit. However even if all of that was possible it would be almost impossible to code that. When climbing you have a very heavy chunk of metal swinging from the bottom of the drone so good luck controlling that. And even if you could do all of that when carrying the portion of the robot with the bumpers up assuming you had enough power and godlike coders you still have to deal with your robot getting bumped around like crazy. If I were to so much as bump the frame it would cause the drone to go wild and probably crash into something and it is very likely that your alliance partners or a defender will contact you at some point.

As an inspector, I would question the safety of a robot (with a big 12V battery) that can fly, potentially over the alliance wall/side walls and put people near the field in serious danger. It’s not like you could auto-disable a drone if it flew over a wall (it could fall and hit, potentially kill someone). Plus, as other people mentioned the power issue is impossible. Though I’d be interested in seeing if this could be done with NEO motors rather than the 775pros - does the NEO have a better power/weight ratio than the 775?

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