1st time swerve drive frame advice

Technical Technical Discussion
#1

Hey so my team is using swerve for the first time with the swerve and steer modules from andymark (am-3009) and the versaframe stock from Vex. We have a basic CAD of the frame done already but I was wondering what some other teams who are a little more familiar with strong swerve frames or just generally strong construction might be able to advise us on. we are planning on using the opening for a large manipulator and are planning to add reinforcement on the side(not the corners because they would hit the wheels) to mount bumpers to. The frame is 31 inches long on the sides and 27 in wide on the front and back the side with the gap is the front.

here is a link to some pics of the CAD:
https://docs.google.com/document/d/15nwlhEYlNbG0De77_YCh6Yox2UWr1AsmObfwE-r0Pmw/edit?usp=sharing

#2

I don’t want to be negative but the consensus here might agree. If you are doing this for the first time AND you have to ask these questions, then swerve may not be for you. I want to say that gently. Swerve done extremely well will only give you a small advantage, and perhaps not even that. Swerve done sub par may ruin your season.

I would make sure you team is clear and agrees as to why you want to try Swerve and what advantage you are seeking by choosing swerve. Is there a better way? Then again you will learn a lot.

#3

QFT

#4

Swerve is a great drivetrain…after you’ve had a ton of practice building and coding it. If you’re doing this for the first time ever, without building/coding practice in the offseason to learn and understand how it works, it can be a hard design to get right. Let alone learning how to drive it effectively.

I think it’s a great idea to implement so don’t let the community deter you from achieving your goals, just understand the added complexity this drivetrain brings.

There are a number of great teams that effectively utilize Swerve and have for years so there’s a wealth of knowledge here to help.

#5

We used the AndyMark swerve system last year and we got fairly lucky with our results. By lucky I mean the system didn’t crash and burn and we had ever so slightly more control of our robot. Our programmers didn’t know how to get the full capabilities out of the drive system and were pressed for time so the control was very limited.

A HUGE word of warning against the AndyMark swerve modules, they use an incremental encoder instead of an absolute encoder unless you buy and install it or install an index limit switch. This means before you start the robot you need to manually align the wheels every time.

When you’re trying to test auto modes again and again, it’s really time consuming to align the wheels, especially if they’re not easy to get to. There’s a lot that could go wrong mechanically and for your controls, and the alignment is up to human error if you don’t have a sensor solution.

I’d strongly reconsider the challenge this year and see if a mecanum or 6 Wheel Drop chassis can give you the same effect without much sacrifice.

Now to answer your question if you really want to continue with this you can see some pictures of how we mounted to it. In one of the pictures notice the plates with the googly eyes protecting the PG motor. The power connector coming off of the PG motor is VERY delicate. Make sure to 3d print a cover for it or protect it in another way because if you lose power to any of your 8 motors on the drive system you’ll basically be dead for the match.

[9 new photos added to shared album] 2017 FRC3236

#6