Quote:
Originally Posted by CalTran
Having read this as well as the pleathora of other threads explaining the pros and cons of swerve, and the 1625 whitepaper on their swerves through the ages, our team would like to pursue creating a swerve drive as an out of season project. No, this does not mean we are going to try and design a swerve drive for the 2013 season.
We are designing a swerve system so that our team will, should the need arise in the future for a swerve drive, have some first hand details on how to pursue a competition swerve drive.
That being said, we had a few questions that I figured ChiefDelphi would be able to answer.
The first and foremost question is the wheel modules and independence of each. As far as we know, there are some basic types of module. independence:
Chain all 4 modules together
Chain each side together
4 Independent modules
If we had to make the decision right now, we would chain each side's module together. Our reasoning behind this is because we believe this iteration is the "simpelest" method of swerve while maintaining some amount of maneuverability. As far as we have been able to tell, the added complexity of 4 independent modules for the added driving tricks added are not worth the time or research.
Is this the right decision? If you could provide personal examples or logical reasoning as to why independent modules are a necessity vs. keeping sides tied together than that would be appreciated.
Secondly, at CTTD this weekend I was fortunately to get a first hand look at 3928's revolutionary swerve drive modules. Between using their modules as a basis for design and buying a WildSwerve module from Andy Mark to use as a model (Blanking on who I saw that did this; been reading too many threads on swerve to remember what came from where) which would be suggested? I am leaning towards using 3928's swerve as a basis for design because it seems to somewhat help with keeping the weight of the modules down.
Thirdly, wiring. The obvious implication of swerve modules are that they are not infinitely rotating, due to the twisting of the power wires. What we would like to know is if it is possible to make one that would be infintely rotating, and how one would design for this. If not then how does one ensure that the position and rotation of the wheels are correct?
If this thread could be kept purely to the physical aspects of swerve that would be appreciated. There are plenty of threads and papers also describing the programming of said drive, and our programmers will visit them as necessary. Thank you. |
You should have found me, so I could talk you out of it.
The advantages to the style of module we used this year were size and weight. It was also easy to mount to whatever frame system we chose, and it kept the COG really really low.
Its obviously incredibly custom and took a large amount of machining and assembly time, I was surprised at how well they held up for being a 1st generation swerve module concept.
You've nailed on one of the main issues with "CIM in module" setups, the wires (kinda annoying). If you can find a slipring that can handle the amperage of a CIM more power to you, it'll save you alot of grief if an encoder ever comes unplugged.
But the resource drain is enormous, and for that reason I do not see us pursuing it in the near future, I'd like to save some time for other parts of the robot so we can put on a little bit better show than this weekend (we were very very far from prepared due to other circumstances).
The technical learning benefits of doing a swerve on the other hand are enormous, from Concept to CAD to Machining to Programming to Driving, you learn an incredible amount due to the complex nature of the system and the level of performance you could potentially extract from it.
For that reason pursuing a prototype in the offseason is fairly okay, just be watchful of the "man this is so cool we should do it in build" as I've embarrassingly fallen victim to it so many times before, with varying results.