First of all, kudos on building such a amazing robot so early in the season looking forward to see what this robot becomes by the end of the season.
A couple of questions:
-Are your wheels being powered directly or is it a drive train?
-Are you planning on increasing to a stage 3 flip out design on the tray?
-What were your plans on defending against robots that ram you to throw cubes off the tray?
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Yes. It is a 600RPM base geared down at 3:5.
Not necessarily as we already have a third section that is linear. We see no need for a third flipout.
Our robot is actually more oriented towards skills (hence the sped up base), so we didnāt necessarily focus on preventing cubes from coming out of the robot.
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Are you using a motor for the arm to put down the cubes?
Sorry for re-introducing a fairly old thread, however I am really curious about the custom omni/anti tip wheels, as I have seen a couple teams with them at this point. Anyone care to share how they are made? Thanks!
they look to simply be the string pulleys with string wrapped around them but has the white nylon spacers going around it. looks as if it just uses the smoothness of the spacers in order to roll, and the grove that the pulley has to keep it seated with the string giving the whole thing tension to keep it all together.
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Alright, thank you
We used a ziptie with white 0.5" spacers on it.
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that is a scary fast drive. how do you keep it from over heating? your driver must be really good to master such a drive train. a lot of good teams here in China use 200 rpm direct drive on 3. 25 inch wheels and they donāt really complain about it being slow. I use 200 rpm on 4 inch omnis. I find it more than enough even for skills. is there any specific reason youād build such a fast drive?
Edit this is even faster than the average tp drive. imo tp required quick field navigation more than tt.
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We donāt really have any overheating issues when under defense or when playing defense (keeping very minimal friction helps a lot). We originally built the base to help during driver skills in terms of manuvering around the field to gather cubes, but we realized that itās just as useful in actual match play.
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Do you guys have an axle connecting both sides of the two bar?
No, we had the lift powered through the 3-wide brace (not through the arms themselves).
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Any tips on making a solid 3:5 drive, my team is really considering.
Build it fast enough for drive practice. That ratio makes the drive almost 300 rpm which is much faster than a lot of people can handle. I heard the upper limit of useful speed is abt 300 rpm so just make sure u can control it
In a recent competition we used a 200 rpm 5:3 drive on 4" wheels. I ran the math and apparently it goes around 6ā per second at top speed (without factoring in the boost gained from voltage control). This speed is manageable, but requires a decent amount of driver practice. Also note that this drive is faster than 600 rpm 3:5 drive on 3.25" wheels by almost a whole foot per second. We definitely were not able to use the speed to its full potential, but it proved useful in several circumstances throughout the tournament. (note that we were not able to get a ton of driver practice in)
All this being said there is a large range of manageable speeds for vex and dont be afraid to switch away from the direct drive to a higher speed drive.
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wow thatās really fast.
I feel like drives donāt really need to be much faster than 200 RPM this season. you donāt have to drive that fast very often like you did in tp, since thereās usually a cube just in front of you. but if your driver can handle the extra speed, then there isnāt really a good reason not to speed up.
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How does the tilt mechanism tilt back and forth and what materials were used?
Should be about that fast, yup. ( I think its 5.81 ft/sec) And I like seeing the drive described in this way. I think so many options are viable with V5 that robot reveals would be most clear if drive was described as ā4 motor, 5.8 ft/secā or similar.
As an aside, it would be interesting to put limit switches on back and front and time it running full field at 100%. Iād be curious if it can get to full speed in the ~2 seconds.
Edit: I guess you would need to involve other sensor to capture the speed in the last 2ā or so.
I decided to go for a 7:5 200 cart 3.25" wheels
I feel like this is a good enough speed for my team and it was fairly simple to build
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I had a 266 rpm drive for a long time, but I changed down to 200 recently. I was not making use of the top speed, and my botās weight worried me that I might burn out the drive motors in continuous usage (which I wouldnāt in a match, but for back-to-back eliminations, it might just be a bit too risky).
My bot is heavy because I use a steel chassis. It both helps with inertial defense, as well as a natural anti tip mechanism in that its CG is naturally pretty low. I do, however, plan to lighten my load once I feel I need to go faster in driving.
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My team (3075b) are looking into a flip out tray, and we need help at looking at to flip out mechanism