I’ve started to design a swerve at least five times, I finally completed one (in CAD). I have the rotating module set up with a ring gear inside it it which will be driven by by a bag motor for steering. I have a Cim driving a gear into the center of the rotating module going down and from there driving a gear connected to the bevel gear then going to the bevel gear on the wheel wheel for drive. There’s probably still a lot to iron out and feedback would be greatly appreciated.
Machinability is going to be near impossible without improvements to the design. I’m thinking about manufacturing it as 2 pieces (ring gear&bottom piece) and taping holes in one half and putting screw holes in the other. Any other ideas for manufacturing the piece would be appreciated.
How about weight?
Inventor says the weight per module will be about 8.873 lbs, a bit higher than what I would have wanted but not without reason for my fist completed module.
What’s the top speed?
I am not experienced enough to get a good speed but I will tell you that the CIM : wheel ratio will be 8.462:1 and steering ratio will be variable with the versaplanetary gearbox.
If you have any more questions please feel free to ask.
We routinely waterjet cut our turret gear with a 20 DP gear tooth profile and have had good success with that. So I think you could waterjet cut the ring gear.
The face gear could be 3D printed and then bolted to the ring gear. The loads on the encoder are low so plastic gear should work fine. Getting that to mesh well with your encoder gear may be a bit tricky, but there are ways to do that.
What are you planning to use for a turret bearing? Is that big white cylinder a low friction plastic (Delrin, Teflon or something) bushing? If so, I don’t think you will be happy with the friction of the system, especially under side loading. I suspect that it will tend to bind and cause problems with the steering control. If you have a bearing somewhere in there, great.
That is on the low end for a swerve; from what I understand you should try to target 12-15 ft/sec (adjusted) as you ideally won’t be in pushing matches so often.
I’m planning on 3D printing the Face gear and the encoder gear.
What are you planning to use for a turret bearing?
In the CAD I’m using a SA035XPO bearing.
That is on the low end for a swerve; from what I understand you should try to target 12-15 ft/sec (adjusted) as you ideally won’t be in pushing matches so often.
I’ll try to play with the gear ratios when I have more time to get a higher speed, thanks for the input.
[UPDATE]
I have split the rotation hub into two parts and have them bolted together in cad for easier manufacturing. I have changed around gearing so now you get at 6:1 one from cim to wheel with an adjusted speed of 12.56 ft/s. I have also chosen the versaplanatery to be a 12:1, with a 12T gear to a 64T ring gear after getting a total ratio of 64:1 from bag motor to turning. Currently the estimated weight is 8.242 lbs, I’m still trying to get that down a bit more, if anyone has ideas of how to reduce weight that would be appreciated.
