06-12-2014 19:30

Abhishek R

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Any plans to put a bunch of weight on it when you drive it? It looks great, will we get to see video ?

06-12-2014 19:31

Gregor

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

I really enjoy the invert CIM stickers.

I'm curious to see how the hex shaft collars on the axles hold up. I've never seen that done on a WCD before, but it seems like a nice way to reduce machining.

06-12-2014 22:36

Arpan

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Anecdote here, but we ran a virtually identical drive last year. They were okay, but we had to tighten them every few matches. We'll probably switch to clips or bolts this year.

07-12-2014 00:41

AKSoapy29

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

We are just temporarily using the collars because we haven't had access yet to the machines in our school. We will eventually replace them though.


And yes, we will try and do a video on Monday

07-12-2014 19:46

snoman

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Looks sweet. What's the pneumatics do for you?

07-12-2014 20:24

Abhishek R

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

I believe it's probably for shifting, since there's just the one tank.

07-12-2014 21:34

AKSoapy29

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Correct, all the pneumatics do is shifting.

08-12-2014 11:09

Dukenator76

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

What is the weight of it with motors and electronics and no battery?

08-12-2014 12:36

blazeflipper

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Very cool Gear boxes! Just curious what are your gear ratios and expected fps when fully loaded with 135ish pounds?

09-12-2014 00:18

nomad725

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

What material did you use to mount the electronics on?

09-12-2014 13:50

llamadon

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Thanks! They are from West Coast Products.

The Ratio spread currently is 2.06, with calculated FPS at 7 in low and 13.5 in high. The drivetrain is currently unloaded (50 lbs roughly,) so we can't really tell between low and high.... They are both stupidly fast. We also purchased two different gear sets, and also pinions. We can configure the drive to the following speeds: 5.5/15 7/18 5.5/18 7/20.5 5.5/11 7/13.5 (low/high)

We'll see how many we have time to actually test.

It is a perforated polypropylene sheet. You can find them online. McMaster Carr has them in stock.

09-12-2014 14:50

AKSoapy29

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Yeah, and the programmers capped the power to 80%!

09-12-2014 15:57

asid61

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Why? You have 6 cims running at <14fps in high gear.

09-12-2014 18:49

Thad House

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

What kind of drive method are you using to drive it? If you are using tank drive or standard arcade drive, it would make it seem like it is really fast and hard to control. I would recommend something similar to Chezy Drive. We've been using Chezy Drive for the past 3 years, and it makes faster robots much easier to control, as long as you put set the gains right. 13.5 fps is fast, but not stupidly fast, which I would consider being 17+. Still anything over 10 fps is hard to control with tank.

09-12-2014 18:51

audietron

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

What is Chezy drive?

09-12-2014 18:55

Thad House

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Its a modified arcade drive. They use 2 separate joysticks. One to control throttle, and one to control turning. Some math actually changes the turning ratio so the robot turns in smooth arcs instead of sharp corners like standard arcade drive would. This makes full speed sweeping turns much easier, which makes the robot more controllable.

Their implementation can be found here.

09-12-2014 18:58

audietron

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

That is essentially what we use but I just called it halo drive. I might just implement the "smooth arc" changes to our drive though to see what that is like.

09-12-2014 20:13

audietron

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

do you have video of the drive running?

10-12-2014 21:47

AKSoapy29

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Of our prototype drive, yes. Our video guy won't be able to render it immediately though :/

And just a linear drive is a bit to uncontrollable, so we are going to try to test out some different math functions for the different gears and see what handles the best.

12-12-2014 10:15

Jay Burnett

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

How do you guys hold the wheels on to the shafts at the end? I'm designing a WCD for our team and was curious how other teams accomplished this.

12-12-2014 11:33

notmattlythgoe

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Our team, and I'd imagine most teams, uses snap rings.

12-12-2014 12:10

Jay Burnett

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

Really? That's what i have in the CAD now, but I was told that those might not hold up under the force of the wheel trying to push off the shaft. Any specific type? Thanks!

12-12-2014 12:17

audietron

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

We use klip rings which are a brand name type ring. They are a special type of e-clip but easy to put on and take off with a screwdriver.
Here is the link to them:
www.mcmaster.com/#98420a138/=uzrf5a

12-12-2014 13:12

AdamHeard

Re: pic: KING TeC Drivetrain Prototype - All Wired Up!

They are rated for a lot of force, and unless the snap ring is damaged by deforming too much during installation (easy to avoid with proper snap ring pliers) they are plenty for the job.