gear box for Denso throttle motor

[Certified Nerd]

My local high school team (5464) has 3 members that used to be on my team (3840). They won the rookie award but came in 56th place out of 59. I don't want to see them get crushed at Einstein, just creamed. They want to put wheels on their intake but they are a rookie team and don't have anymore motors besides the throttle motors. Given the incredibly high cost of going to internationals, they don't have any spare money. I calculated that the throttle motors, once gear reduced, should have enough torque to suck in totes. Thanks for the input everyone.

[Certified Nerd]

Here is the first part: http://www.thingiverse.com/thing:710907

[asid61]

Looks good so far. How is that mounted?

[Certified Nerd]

I haven't decided yet.

[Gregor]

Originally Posted by Joe Johnson

We have 14 Banebot motors on our robot this year. 11 of them are connected to Versaplanetaries (the other 3 are driving our Wild Swerve modules via CIM-iles).

Given that the PDP only has 16 spots for motors, I assume you are using 3 CIMs or MiniCIMs as drive motors, R42 limits you to 1 motor per speed controller, how are you using 17+ high power motors in 16 PDP spots?

I'd also love to hear what each motor is powering, sounds like a complicated robot.

[GeeTwo]

Originally Posted by Dr.Gusta

Who cares about the practicality or the possible future uses of this gearbox, for this motor.

I do - because I'd like to be able to use these motors for something other than filling up a storage bin that we have to upsize every year or two.

[Dr.Gusta]

Originally Posted by GeeTwo

I do - because I'd like to be able to use these motors for something other than filling up a storage bin that we have to upsize every year or two.

I 100% agree with you. I was addressing those questioning the practicality of this project and not recommending features or design approaches.

[GeeTwo]

Originally Posted by Dr.Gusta

I 100% agree with you. I was addressing those questioning the practicality of this project and not recommending features or design approaches.

Yes, I knew I was preaching to the choir in your case, but I also wanted to reiterate that this project is practical, and probably would be utilized by a significant number of teams if the cost point is right. There will always be naysayers, and arguments of economy will never resonate with people who have more dollars than sense.

[asid61]

For the record, I might use this or a variation of it to allow all of our veterans to design and build a gearbox over the summer. We have tons of throttle motors that they can use to test with.

[GeeTwo]

Originally Posted by Joe Johnson

We have 14 Banebot motors on our robot this year. 11 of them are connected to Versaplanetaries (the other 3 are driving our Wild Swerve modules via CIM-iles).

Originally Posted by Gregor

Given that the PDP only has 16 spots for motors, I assume you are using 3 CIMs or MiniCIMs as drive motors, R42 limits you to 1 motor per speed controller, how are you using 17+ high power motors in 16 PDP spots?

I believe he means that he's using these three Banebots as drive motors; no CIM or mini-CIM. They are presumably steering with 3 (or perhaps 1) through Banebots + Versaplanetaries. After gearing them down with the CIMile, it appears that they can get good low-speed torque for a smaller current draw than a CIM. The trade off is loss of peak power in the 30+A part of the curve, where you don't spend much time anyway. It sounds like a good performance trade off, especially for this more deliberate game. It doesn't surprise me that they're blowing motors; smaller means hotter for a given amount of power.

[Joe Johnson]

Originally Posted by GeeTwo

I believe he means that he's using these three Banebots as drive motors; no CIM or mini-CIM. They are presumably steering with 3 (or perhaps 1) through Banebots + Versaplanetaries. After gearing them down with the CIMile, it appears that they can get good low-speed torque for a smaller current draw than a CIM. The trade off is loss of peak power in the 30+A part of the curve, where you don't spend much time anyway. It sounds like a good performance trade off, especially for this more deliberate game. It doesn't surprise me that they're blowing motors; smaller means hotter for a given amount of power.

Ok so here's the deal.

We started with 3 CIMs on our 3 WildSwerve modules*. Then we needed to save weight (big surprise). We noticed that the CIMs were never getting even warm in practice with our wooden "drives like" practice chassis (nick named Trojan -- get it?). So... hey presto, we started using Mini-CIMs and pocketed 0.6lbs per motor (1.8lbs when you're over weight is like manna from heaven).

We are now 1 week to Bag & Tag and we still need to shave some weight (yeah I know another big surprise). Looking at the power, a BB 775 motor has more Peak Power than the Mini-CIM. A CIM-ile from VexPro makes the BB 775 output shaft and mounting look like a CIM/Mini-CIM. And saves about 0.9lbs OVER A MINI-CIM!!!

The 775 hangs out a bit over the 2.5" Diameter of the CIM so we had to do some grinding on the WildSwerve plates and shift the orientation of the mounting screws, but all in all, not that much work for 2.5lbs very late in the game.

As to overheating, this year's game does not put much stress on the drive motors. The field isn't that big plus acceleration is not the best idea with a 5 stack on our forks...

So now you know.

By the way, it's our steering motors that do the most work and get the hottest (by far -- all the other motors are not doing much work and/or have beautiful counter balance systems).

Dr. Joe J.

*which are working awesome for us -- thanks 221 Robotic Systems/Anthony Lapp for the team sponsorship, but even if I didn't have them as a sponsor, I would say the same.

Side note: If you are a team thinking of doing swerve for the first time, seriously, buy the mechanical bits first, get them mounted to a chassis (including your sensor scheme) and get that chassis in the hands of your coders and then your drivers. SO many teams that try swerve for the first time have such a lousy experience because they take so long getting the mechanical hardware designed and debugged, the coding team barely has time to get anything working yet alone giving drivers stick time -- and time to slap the coders upside the head for the goofy User Interface they've most likely come up with ;-)

Point is that it takes iteration loops to get this right and those take time. Don't be learning lessons during you qualification matches. /end soap box rant/

[marshall]

Originally Posted by Joe Johnson

Side note: If you are a team thinking of doing swerve for the first time, seriously, buy the mechanical bits first, get them mounted to a chassis (including your sensor scheme) and get that chassis in the hands of your coders and then your drivers. SO many teams that try swerve for the first time have such a lousy experience because they take so long getting the mechanical hardware designed and debugged, the coding team barely has time to get anything working yet alone giving drivers stick time -- and time to slap the coders upside the head for the goofy User Interface they've most likely come up with ;-)

Point is that it takes iteration loops to get this right and those take time. Don't be learning lessons during you qualification matches. /end soap box rant/

I completely agree with this. We did swerve this year for the first time and it is VERY programming intensive. Also agree with Anthony and 221 being awesome. We went through 3 or 4 different control schemes and we're still not done. It's an AMAZING drivetrain but it takes a lot of code to make it work and work well.

Seriously, back to these gearboxes. How do you handle the power leads being next to the output shaft when you create a gearbox? How do you mount the gearbox to the output?

[Certified Nerd]

Originally Posted by marshall

Seriously, back to these gearboxes. How do you handle the power leads being next to the output shaft when you create a gearbox? How do you mount the gearbox to the output?

My plan was to cut the tabs shorter and, for now anyways, solder directly to them. As far as I can tell the rules allow for this, but I forget where.

[GeeTwo]

Originally Posted by marshall

How do you handle the power leads being next to the output shaft when you create a gearbox? How do you mount the gearbox to the output?

You beat me to the question. the wires just go through a grommet on the swerve module, and I don't see any slip rings or other way to manage that wire on the steering module either.