You should team number up, kyle. That pneumatic lift was pretty cool at least.
Back on topic as well, I’m going to attempt to get my team to consider switching to a two motor lift and six motor drive, we want to keep our speed but add weight (pneumatics), and that seems like the easiest way to do it.
Refs are required to call whatever is in the rules. If your robot gets tipped over and they don’t call it, there’s a protocol for bringing things to their attention. If you don’t follow it, then it’s no longer on them. And what do you mean by “battling for a trough”? Because AFAIK, there’s no provision for that in the rules. The provisions that Karthik has laid out are basically obstructing access to the field, or covering the tops of the troughs to prevent access AFTER EXPANDING HORIZONTALLY. Now what that means we can debate based on individual robot designs, but as far as tipping goes there’s nothing in the rules that makes it legal to tip robots based on light scuffling.
Because it is not legal to tip anyone. Get in their way passively, don’t lift upwards and start throwing them back. Don’t go ramming people with their arms way in the air.
If we’re playing too conservatively, please let me know. Because I’d be thrilled to learn we can be more aggressive.
Ephemeral_Being, every region is very different, your ref’s are different from mine. New England has been known to be a very defensive state, and being aggressive in terms of pushing at each other over the troughs is common multiple times a match. Perhaps in my region the refs allow too much to go (which personally, fighting and being aggresive with other robot’s, to a limit, is a lot of fun, as long as it stays under control), or perhaps your ref’s are too strict. There’s probably no way to know until worlds.
Anyway back on topic…
If we’re able to play super aggressive, adding more motors to the arm to throw other robots is a fantastic plan. That was why I was trying to get some direct answers out of people about tipping and stuff.
The solution here is to read and understand the rules fully. On the topic of tipping, rule G11 states:
Thus, tipping is only illegal if it is ruled to be intentional or egregious. Incidental tipping is not punishable by a disqualification. Ultimately it is up to a ref to decide whether a case of tipping is egregious or intentional. That being said it is usually extremely obvious when a case of intentional tipping happens, so have fun if you plan to design your robot specifically to tip other teams…
Who would ADMIT to having two extra motors on the arm to tip robots easier? Just slightly lifting up with your arm would start a tip, and it would be near impossible to prove you did it purposely.
This isn’t really the way we’re supposed to play the game, but I’m just throwing it out there as an idea for teams doing a redesign before Worlds.
I never said a team would admit to putting extra motors on their arm to tip. I said it was typically very obvious when a team is involved in intentional tipping. While it would be near impossible to “prove” it was intentional, the ref doesn’t have to prove anything. They will disqualify the robot if they think it was intentional or egregious, period.
So, then it comes down to defining what that is. Here in Arizona, we got yelled at for bumping into each other. Apparent in New England, they got away with a lot.
Watching Nationals, a bunch of tipping occurred that would have been called down here. We’re going to have to adjust.
I would add motors to the intake.
My reason is that if you’re not grabbing all the sacks at your top speed, you’re wasting potential of your drivetrain. Why would you even start with a high speed drive if you aren’t using it because you’re grabbing? For a majority of the match, you’ll be attempting to grab or de-score. If you need to worry about protecting your troughs, have the robot with more motors devoted to their drive to protect them, not the one with high speed. In addition to the intake power, you should be able to de-score more sacks faster. Another reason why you want more grabbing power is when you battle over sacks. If you and your opponent is battling over a sack, you can guess that the robot with the stronger and faster intake will get the sack.
I would not place extra motors on the lift because of gear ratios, elastic, and counterweight, and pneumatics. With gear ratios, you’ll lift slower, but you can lift whatever you need. With a slower lifting speed, you can ether accommodate by combining controls such as raising early while driving or simply preparing for a proper de-score. However, with gear ratios, you start placing more stress on axles. Twisting, you can solve through reducing jerk, reducing space, or decreasing the weight on the axle. Rubber bands can help with that task as well as grant power (of course you have to deal with varying power levels as the lift changes height). Counterweight will help solve your lifting issues, but may make your axle issues bigger. Though i never used pneumatics, i don’t think it’ll damage the motors if you mix the systems.
Now for drivetrain, i don’t see the purpose of having an uber fast drive that sacrifices reliability. The most important sacks are the “neutral” sacks under the trough, which don’t require much driving to get to. If you can snatch those without getting your clustered sacks stolen, you should be good. Because of this, speed becomes less critical, and you can lower the ratio of your drive. With this however, you may need to start adding emphasis to holonomic or autonomous. If you must, maybe you can develop a heat sink using the 1x25 bars to make your drive motors more reliable. Now for a defensive struggles. One way around this is applying a flip out ramp around the sides of the robot will nullify any pushing. Rather than pushing your robot directly, they start pushing at an angle and a chunk of their force is eliminated. If they chain/gear the wheels together, more strain is placed on their back axles/chain. Because of this, they may actually start damaging their drive.
Explain how to do that, please.
Actually, not confused at all. I will tell you right now: If you start ramming me and trying to push me I will make sure you’re pinning me. Really not that hard to do.
This is <G8>
Yeah we do get away with a lot in new england… for example… well I have to ask Robert if it would be okay to show the video… but I beat the legendary 4886a via borderline illegal means… aka pushing and possibly even tipping but the robot was already super tippy and trying to descore my trough… this same match also included the iffy robot sandwich that was asked about in a QA recently…
Anyways Owen I suggest if you are doing a chainsaw intake go with a 3 motor lift 3 motor intake… and do what someone else suggested heat sinking the drive motors… that way you may be able to do a 5:1 lift ratio…
It’s harder than you would think sometimes. We’ll see if you can pull it off at Worlds.
Sorry, I meant <G11>. I have most of the rules memorized, but my memory of which is which still seems foggy.
Last year at worlds I tipped 6? robots. Of those 6? I was called for tipping and DQed once. I had a 6 motor drive and spent a lot of my time pushing robots around the field and the robots that were top heavy tipped over.
If you try to break someones robot it is a DQ but that doesn’t mean pushing blocking or fighting over a trough is always a DQ.
See, this is the ruling I was hoping to hear. We LIKE aggressive defense We find it fun. We were a bit depressed we weren’t allowed to play much in-state.
currently i have:
4 x 393 drive (160rpm)
4 x 393 lift (100rpm)
2 x 269 intake (100rpm)
works well, drive is fast and efficient, lift is at a 1:9, lifts fastish, and can lift multipul sacks plus our heavy steel arm, and intake is geared at 1:5 and works really well at intake
all our drive is on power expander … 2-5
The more motors on the drive, the better. (within reason of course) If you can do something without a motor, do it. Save them motors for the drive.
Assuming it’s a 393
grab a 1x25 bar (Aluminum is a good heat sink), cut the bar so there are 12 holes. Bend it with a clamp and create a box that is 4x2 holes. Use pliers to get accurate 90 degree angles. Wrap it around a motor by pulling the corner that’s not connected. Remove it after every match and let it cool and you should be fine. If you have issues with the keeping it on, bend an angle so it clamps onto the motor slightly. The metal pulls the heat to the surface where it can cool down through moving air. Use the spare 1x1 metal as a spacer/decoration/etcetera. What’s also nice is that metal starts off cooler than your motors. Because of this, you can almost think of it as cold armor you need to burn off before it turns into a heat sink.
Your motor should be fairly accessible so you shouldnt have problems removing and moving the heat sink.
Works better with old, bent up bars. The slight bumps increase your surface area to volume ratio.
If you leave your custom heat sink and motors to cool off for a bit after a match, they’ll both eventually drop back down to approximately room temperature. The metal isn’t actually colder, but since metal is more conductive than the plastic casings of the motors, it feels cooler as heat is more readily conducted from your hand to the metal.
Your whole idea is interesting (not sure how effective it is without thermal grease), but just wanted to correct a point of physics here.
He’s right, without thermal grease this won’t make much of a difference, and the plastic case of the motor actually acts as an insulator between the actual motor and the custom heatsink…
I’d love to see some actual tests with an idea like this (control motor w/o heatsink, motor with heatsink, motor with heatsink and thermal grease). I would be interested in seeing how much of an advantage it would actually give.