Online I see teams either having a metal piece after there wheels or just there wheels and a collar to lock it in.
What are the pros and cons for doing either one? Also why do most teams usually have metal after there wheels?
On a side note my teams drive train when full power forward or backwards we start to curve? Does this relate to having our wheels outside with no metal piece after.
Lastly our robots wheels are slightly bending in towards our base does this relate to any of previous things i said?
I don’t know what you really mean by metal pieces after the wheels, but generally axles need to go through two pieces of metal and two sleeves. This is a good habit to get into to prevent any sort of bending. Additionally, wheels should be enclosed to prevent any damage to the wheels, axles, gears and motors when robots collide. To address your curving problem, its just the random friction or differences between motors and wheels that causes that. If your drive train is thin enough, you can try to put the driven wheels on the same axle. If not then you should utilize shaft encoders to change the power of a motor depending on if one side of the chassis is moving farther than the other.
on my current designs the second piece of metal adds support, reduces entanglement (allot) it acts as a bumper when robots collide (and with my aggressive driver it helps allot) and adds durability to the design. it also saves space and just looks good. it looks like a finished competition robot, like we really took the time and went the extra mile to assure everything works right, and it allows room for building at the tip of the 18x18x18 window for supports or other things
Cantilevering the axles (supported on only one side) is generally not advisable. Like many of the posts have said, having metal support on the other side (connected to the rest of your structure with braces or standoffs) is more structurally sound, minimizes snags during robot melees and is just generally more durable/reliable.
Further, this would address your problem of “wheels slightly bending in towards [the] base”, as unsupported axles tend to bend perceptibly over time. This happens especially if the unsupported distance is longer than let’s say zero [flush w/ structure], and if you put your robot into a period of storage, the axles will bend upward due to the weight of your robot.
Advise you close an outer box of structure that supports the wheel axles. Even at the cost of shrinking the L to R wheel distance slightly if you are already at 18 in. Also, use standoffs.
“Online I see teams either having a metal piece after there wheels or just there wheels and a collar to lock it in. What are the pros and cons for doing either one? Also why do most teams usually have metal after there wheels?”
Having a plate on the outside and inside of the wheels that is soild will provide a ton of support to the robot allowing for less friction in the drive.
“On a side note my teams drive train when full power forward or backwards we start to curve? Does this relate to having our wheels outside with no metal piece after. Lastly our robots wheels are slightly bending in towards our base does this relate to any of previous things i said”
The fact that you dont have a support on the ends of the wheels will increase the frinction of the wheels as well as amplify the affect that each and every motor does NOT run at Exactly the same speed. I.E your curve of the robot begins to happen. We have the same problem just on a minor scale. Also the wheels bending in is a result of puting a lot of weight on the wheels with Little To NO support. Adding the second Plate on the out side will help tremendsly
Here is a pic of our robot to help u with the ideahttps://mail.google.com/mail/?ui=2&ik=e0beddd9d9&view=att&th=13366943b6c075eb&attid=0.0&disp=inline&zw
So basically the C-Channel or whatever on the outside is just for support of the Axles. The wheels would go in between the C-Channel, and the bars going across are for support.
We are using this drive train this year with omni’s in front, and traction in back.
The robot drive train that you decide on needs to have sheer strength to get out of bad situations. Example: If a robot is blocking a goal that you need to double, the only way to score on that goal is to push them out of the way. For sure the drive train is the most important aspect of the robot for this game, so think wisely about chosen your drive train.
