How many Versaplanetary gearboxes do you have on your robot?
What gear ratios are you using in your Versaplanetary gearboxes on this year’s robot?
How many single stage (10:1 or lower) Versaplanetary gearboxes do you have on your robot? Why did you choose to use a Versaplanetary for this low torque application?
We pretty much used VersaPlanetaries all over the place this year and have been pretty happy with them. Overall we have 7 total:
-5 on drive @ 7:1 driven by CIMs
-1 for our belt feed to the shooter (don’t remember the ratio here)
-1 for our climber @ 70:1 (and then another 2:1 spur gear stage after) driven by a 775 pro
We used just 1: A 7:1 x 3:1 on our climber with a dual input to fit two 775pros. We only missed 1 attempted climb all season IIRC. That being said, I hate how the input plates and dual input are only plastic, because we took a side hit one match and broke the dual input. After that we added a thick aluminum guard plate.
We used a versaplanetary with a 63:1 ratio for our climber, and we had a lot of problems with it… we broke 2 ring gears and a couple of sun gears. Let’s just say I have become a master at disassembling and reassembling them.
701 used 2 12:1s on our climber. 3 3:1s on our shooter, 1 10:1 on the ball intake, another 10:1 on the gear intake, and a final 10:1 for the shooter feeder. Also a 50:1 powering the turret.
We are using a few VP’s on our robot this year:
We have had very few issues in the past few years of very heavy use.
Care to elaborate on yow your drivetrain uses 5 VPs all powered by CIMs? Are you using them as your main drive gearboxes (because I did’t think they could take that kind of abuse)? How are you using 5 of them?
My guess is H-Drive.
We have 3, all with 775pros: a 7:1 on our intake, a 10:1 on our shooter feeder, and a 1:1 on our shooter. You may ask why bother with a 1:1, we’ll it let us conveniently package an encoder (SRX mag encoder) in a tight package. We had zero room on either side of our shooter shaft, but we were able to package the shooter motor nicely (and we had all the parts on hand to do it).
This should provide a hint to you Ginger Power how applicable Versaplanatary transmissions are each and every year. Designing for them in a handful of your robot’s systems allows you to standardize across your entire robot.
Additionally, from a prototyping perspective, it’s always great when you have 3 separate ratio combinations lined up to test one after the other.
What motor are you using for this?
4 total for us all with 775s:
3:1 on our shooter
12:1 on our ball intake
81:1 on our climber
15:1 on our ball elevator
The only one that had broken so far is the sun gear in the first stage of the 81:1
VersaPlanetary gearboxes with 775Pro motors is my go do solution for every place I need a motor.
VP’s let you be wrong late and still recover. You can get the gear ratio wrong. The motor power wrong (though, if you start with a 775Pro there is no were to go but 2 775Pros). The output shaft wrong (but really, you should just use the 1/2 hex unless you can’t fit it, then use the 3/8 hex – listen to me, I know what I’m talking about here ). And you can go to your box of VP stuff and just Lego together a work around.
I rebuild a climber transmission for a team today in the pits at the NE districts in Rhode Island. They had a CIM and another brand of gearbox.
Switched the motor (to a 775Pro of course), picked a ratio that I knew would work given their drum size, selected a 1/2 round output shaft (cause that is what they needed to transfer torque to their drum) and hey presto, they had a new climber motor/gearbox.
I love the VersaPlanetary system.
Highly recommend them.
Dr. Joe J.
P.S. When I was on 246 in 2015, I helped build Scorpion. I think it had 11 VersaPlanetaries on it (with Banebot 775 motors – which are very nice motors too. Just not as nice as those 775Pros).
1712 is using two VersaPlanetaries this season. We have a 775Pro 10:1 on our gear intake and a MiniCIM 15:1 on our scaling drum. Both of these have additional chain reduction after the VP.
We have 4: a 50:1 on a Mini CIM in our climber, a 3:1 on a Mini CIM in our shooter, a 100:1 on a BAG motor in our ball-feed auger, and a 50:1 on a BAG motor in our fuel agitator.
Team 8 is using a 775pro + 63:1 VP on our spool climber and a BAG + 20:1 VP on our gear slider mechanism (check our reveal vid here if you are interested in what a gear slider is: https://www.youtube.com/watch?v=hg4vbH9MG4k).
The v2 model is great because it allows you to easily take the motor off without removing the entire gearbox. I am pretty confident in saying that our team has never had a VP fail on us (unlike BB planetary gearboxes).
10:1 - 775pro - 1/2" Hex - Intake
30:1 w/ Encoder - BB550 - 1/2" Hex - hopper/feeder
10:1 w/ Encoder - 775pro - 1/2" Hex - elevator to shooter
70:1 w/ Encoder - BAG - 1/2" Hex - Turret
25:1 w/ Encoder - 775pro - CIM Output - climber
We’re doing an H-drive this year, so one planetary per wheel. After the planetary, there is a 1:1 gear drive to the actual wheels so that we aren’t putting an axial load on the planetary. We’ve gone through one competition and an upwards of 30hrs on the practice bot with no issues.
The main motivation for using the planetaries was to allow us to get the H-drive up and running ASAP to give programmers as much time as possible to work on it. They also allowed us to stick the CIMs in the very corners of the drive base, leaving the entire middle open to work with.
Additionally, after our first competition last week, we felt we were too slow, and so we’ll be able to fix that pretty easily by just swapping out the gearset from a 9:1 to 7:1 at SVR next week.
If done correctly, the Versas are very versatile.
This is the first year my team has used VersaPlanetaries on our robots, and we have a total of 3 on each robot. After making some mistakes with gearing by using belts with pulleys (and not being able to fit a better size pulley), I already have it in my head to just use VersaPlanetaries everywhere possible. I originally wanted to use more but the price after adding everything up was somewhat discouraging, but the gearboxes can be reused and as others have pointed out, are extremely versatile.
For our uses, we have 1- gearbox on each of our robots (1 practice and competition) that runs a lead screw for our claw. It is geared 7:1 (we tried 5:1 which was okay but didn’t have enough for our uses, and 4:1 which was too quick, not enough torque) and runs a modified left hand and right hand acme thread 3/8" - 12 screw. The gearbox never has failed us in this application, and was actually able to overcome the additional torque of us bending the lead screw (due to running our claws into a wall). Some of that was due to the motor of course (Bag Motor) but I did rebuild the gearbox whenever this happened so I could inspect wear and regrease.
The second place we used the gearboxes were in our climber. We originally had a 775 Pro driving a 100:1 gearbox (2 - 10:1) but ended up destroying the final stage due to the amount of torque. We didn’t move away from the platform but geared the gearbox 80:1, (1- 5:1, 2- 4:1), then additional chain reduction to take strain off and get to 100:1. We discovered only when we got to the event (even after extensive testing) that the climber did not work, we would go up, stop, go up, stop and never made it to the top. With quick thinking, we changed one of the 4s to a 5, getting a final reduction of 125:1. It worked perfectly and we got all of the climbs except one (rope issues) after that. In between our events, we regeared our climber back to the 80:1 we had before our first event, but added a second one for a more reliable climb. So far everything is working great.
Sorry for such a long story but just want to show how much I love these gearboxes, such a versatile platform allowing for quick second changes, and if we used a different platform, I don’t see it working as well. The key to this we discovered is grease. Always put grease because at the end of the event, it seems to almost disappear. Before we put the gearbox back on the robot, we run the gearbox by hand, and if there is any catching or weird feeling in the gearbox, it gets taken apart and the process starts all over just to ensure nothing wears abnormally.
Our climber uses a 25:1 with the adapter for a CIM. Our shooter has a dual input into a 3:1.