Power Racing Series, The Write-up Part 1 (Framing the Experience)

By jim-shealy on

For all you who’ve been wondering what’s been going on with the power series racing, it’s been a long road, but we’re finally getting close to finishing this year’s kart! Will, Kevin and I (as well as so many others!) have been learning a lot with this project, but before I go into a breakdown of what we’ve learned, here’s some photos (you may need to go to flickr for all of them to show up) and a video showing a snippet of the ~25min endurance run performed over the weekend to test battery life!

This is going to be a post of my personal perspective (Jim Shealy) as the leader of Power Racing Series at the hive, where we’ve been, where we’re going, and what we’re doing now.

So what is Power Racing Series at the Hive?

-A learning experience to get to touch every part of the Hive

-An Introduction to Electric Vehicles and show that, hey, it’s not exactly rocket science

-A chance to collaborate, and produce something as a collective that the Hive gets to show off

(click picture for the whole photo album)

Power Racing Series

 

Continue reading the meat of the post:

If you’re interested, we do need help putting together the shell that we’ll use for the race. While I’d like to do some variation of the pig, we may go with whatever’s easiest, even if that’s making it look like a brick. We are planning to shoot for the New York World Maker Faire, and we will need a small skeleton crew of at least 2 drivers to participate! That means let me (Jim Shealy) know if you’re <180 lbs and if you’re interested. (It’s unfortunately a reality of the current drive train design, and not something we have time to fix for the faire (I’ll get into details next post, bur for now the issue is known, and as long as we’re careful, I don’t think it will pose a problem)). After the faire we can try and let others drive the go-kart.

What are the goals in racing?

-Learn

-Have fun

-Don’t come in last

-Finish the race

So what have we learned? Where did the funding go? Why didn’t we race in detroit? (or Kansas City, or Ft Wayne, or Atlanta last year)

Simply put:

-Unwieldy expectations

-Inexperience

-Scheduling is a $%@#

From the beginning…

Well, as with any large project, there are constant setbacks… or perhaps we should call them learnings. Lots of learnings. We shot for the moon on this project, and as it turns out getting to the moon takes a lot more than you’d initially expect. It was the Apollo 11 mission that actually made it after all.

Anyways, when we started it was fresh off the rush from the 2014 detroit makerfaire. Charles Guan and his MIT team put together an incredible (albeit unreliable) “ChibiMikuVan” and a detailed writeup of the build process. I was excited to see if we could put together a concerted effort as a makerspace to see if we could compete in the Atlanta event two months later. I mean, if we could show up and compete with MIT and I3 detroit, or other well known orginizations, how cool would that be?

Thinking it would be as simple as slapping a motor on a welded together frame, a little arduino here, a little design there, and blam, we’re out the door we got off to an exciting start:

We started off on the coattails of Charles’ MIT Silly Go Karts course material, I taught a class or two, and I jumped into things I was in the process of learning about good engineering design from GE. Quite a few of the guys even got to sit down and learn some introductory solidworks as we settled on making a pig racer:

There was a lot of good times making decisions, putting together matricies, and just going through a streamlined process of figuring out a goal. two or three weeks in we had a “design” and were off to the races with making it happen.

Reflections on our expectations

Looking back it’s worth stopping and making a very important observation. We as the Hive like to dream where we can go without paying attention to all the steps inbetween. It’s a normal human thing, and I’m for sure extremely susceptible to it. A project to hack a kids toy into a serviceable electric vehicle became a quest to build everything from scratch. You can read in a bit of ego here because I REALLY wanted to show that we could do what the MIT guys did, I think it was one of the reasons a lot of people got involved actually. It’s exhilarating to think about all the things we could do, and how we could make a name for ourselves.

I know that we still can actually,

BUT

Its that in-between state of not having done something, and a polished product is something we need to pay more attention to. The only way it happens is through experience, like the last year of Power Racing Series.

A brief synopsis of our competition

You simply can’t go from having riden an electric vehicle I “built” (involving adding motors to an existing vehicle), to teaching a class (which I’ve never done), designing and building a go-kart from scratch (which I’ve never done), and putting a human capable electric drivetrain together (which I’ve done once) with significant battery and power restrictions (which I’ve never bothered with). It can be done, and in fact we’re almost there now. The video above shows that it can be done, but you need to understand how much effort it takes to get from where we were at last September and where we’re at this august.

I should also note that Charles Guan has a rather long and extensive history of building electric vehicles. Some of which looked like this:

It’s pretty well done, but it’s not polished.

oh, and it quickly turned to this because of not thinking through driving ine rain without waterproofing:

Oh, and if you ever meet some of these guys you’ll also see huge scars on their knees and elbows from wheels exploding, shearing, axles snapping, hitting a small rock, forgetting to install brakes…

it’s blood, sweat, and tears over a few years and thousands of dollars of iterations. Seriously, it’s what these guys love doing, and they’ve been doing it for a while.

Learning 1:  it takes a long time and continuous trial and error to do something well.

We’ve come a long ways my friends. A LONG ways.

but from what I’ve seen we did this all backwards. We tried to go from zero to hero and got pretty stuck. It was a difficult few months for me to see a lot of the original crew disappear because of some mix of my ego, slow progress, boredom, or whatever it was. but we stuck it out, and for a month or two, dispite buying the core of the gokart, we really hadn’t figured out how to DO anything. We really had only done things I knew how to do, which was buy components to put on a prebuilt (and nonexistant) frame.

(it’s not just as easy as taking measurements (although it is important!))

This is also the point where scheduling became a real issue. It’s fine to use a Saturday for a week or two, but after two straight months of Saturdays, most people want their weekend back or have conflicts. I had also lost my steam from Detroit and didn’t have time to try and teach the class part of it anymore. I should note that I’m extremely grateful for all the time everyone has contributed to this, despite the lack of direction for a few months! I also got busy, imported a car… yeah.

This left just Will and I to work on the go kart, with a few others occasionally jumping in. I was trying to still get others involved and was pretty indecisive on what to do. I was stuck in the quagmire of thinking I had to CNC out drivetrain components (so we could use everything in the space) because it would be cool and look good.  After a few months of being pestered about not having anything I finally gave up a bit of ego and decided we would try and prototype. Even though it would look pretty awful, it would get us moving and maybe bring some confidence back to the hive that this project was going somewhere. This was the first step in the right direction.

Learning 2: let go of your ego and try and make something, even if it’s fugly. 

So let’s show how the Kart frame progressed, we’ll get into the drivetrain etc in another post as it was its own 8 month saga, but for now the actual structure of the kart:

The beginning:

It wasn’t pretty, but we got to try steering which had had me absolutely stumped for a few months (hence continuing to fiddle with the CNC and drivetrain). Will had an idea based off of a recumbent bike steering mechanism. We ended up deciding that we hated it. It was AWFUL to use. but I’ll be damned if it wasn’t something. It also fulfilled the tripping hazard requirement that Bill S kept asking us for.

Even though it was awful, we still had the chance to use it to drag around a minecraft pig float for the reds opening day parade that Elly H made. It. Was. Awesome. I really can’t say enough how nice of a job Elly did on the paint and putting it together quickly. It really looked like the pig from minecraft (even though we forgot to put legs on it!). It was nice to get positive feedback for the first time in a while and realize that we could get something accomplished!

 Learning 3: even the fugly start will get a lot more use than you’ll realize

Turns out the frame, although derpy looking, was actually pretty strong. While I had my heart set on using metal for metalworking experience in the group, wood is a really good way to go. Actually, a lot of successful (IE didn’t break structurally and finished well at the 2015 detroit races) had a decent amount of wood in them. Its strong, easy to work with, and easy to repair if you break.

There was a LOT of wood (and metal) under this guy. Oh, and it never stopped running. It wasn’t fast, but man did it last.

 Learning 4: If a low tech solution works well enough, you probably don’t need a high tech one

Version 2 of the Kart:

after much fiddling with the drivetrain that I wasn’t happy with, it was redesigned and a metal frame was put together. This time the steering was based off of pictures of actual go-karts. The steering was crude, but worked worked pretty well honestly. The frame was much too weak however. One of the heavier guys sat on it and it bent a bit, I don’t want to think how bad it would be going over the first bump under power, or an entire enduro race… Another reminder that the wood member we had originally was actually very sturdy, and probably is worth looking into for next year.

Learning 5: Don’t reinvent the wheel, if you google “go-kart”, and the part you’re designing looks the same on every one of them, you should probably start with that design

but alas, we needed to make progress and do something that was ride able, so we forged onward with a somewhat beefed up iteration of this design.

Version 3, Much Pig Very Topple

so this one was very much like a pig. We built the box, and by golly you could ride this pig like an actual minecraft pig.

But

No

It never ran (further drive train frustrations). And after a few comments, I never tried. Sometimes you just have to see something to realize how ridiculous it is. While I would like to try this again sometime with better stability, it was just obviously unsafe, even when stationary. I’ve seen what serious road rash looks like, and I knew this was a one way ticket.

Learning 6: Plan time for complete redesigns. Sometimes you get there and realize you’ve REALLY screwed up

Also we learned that the wheels… they really needed to be doubly supported. This version had some mad camber on the wheels no matter how tight we tightened them. I was also later informed by Kevin S that we would have cracked and sheared through the welds on the square tubing had we tried to drive it.

Learning 7: If you’re using something outside its designed intent, at least wear safety equipment because it’s going to take a couple iterations to get right

Version 4, Teach us Sensei Kevin

so about this time Kevin S got involved in the space because of the Power tool drag racing. Turns out he’s riden, made, and worked on gokarts, cars, bikes, etc professionally for a LONG time. he was a breath of fresh life into a nearly dead Power Racing Series Kart. We had to listen and accept that yes, we did need to completely redesign the Kart again.

But I’m really glad we did. It turned out MUCH better than expected!

It was all because of a very fortunate find of Kevin’s that brought in a kid’s electric Quad (ATV).

This made for a very important and missed learning about designing one of these vehicles:

Learning 8: buying a solution that you can modify is MUCH easier than perfecting a solution that you try to make yourself, and will probably save you lots of time and money in the long run

What was so great about this? Well, the quad had 4 tires and steering that’s basically rated for what we’re trying to do already. We don’t have to beef them up much. The rear drivetrain though was the golden ticket. It has: an integrated disk brake (we modified for better braking) a sprocket pre-mounted, a proper shaft, mounting for shock absorbsion, and most importantly, a motor that aligns with the drivetrain with a PREBUILT DRIVETRAIN WITH THE CORRECT GEARING.

basically, we needed to mount electronics, revamp the steering, and it’s a mostly built go-kart. The reality took a bit more effort to get right but…

…ultimately this is the frame we’re sticking with for this season.

So what did we learn on the frame?

Learning 1:  it takes a long time and continuous trial and error to do something well.

Learning 2: let go of your ego and try and make something, even if it’s fugly.

Learning 3: even the fugly start will get a lot more use than you’ll realize

Learning 4: If a low tech solution works well enough, you probably don’t need a high tech one

Learning 5: Don’t reinvent the wheel, if you google “go-kart”, and the part you’re designing (steering) looks the same on every one of them, you should probably start with that design

Learning 6: Plan time and money for complete redesigns. Sometimes you get there and realize you’ve REALLY screwed up

Learning 7: If you’re using something outside its designed intent, it’s going to take a couple iterations to get right

Learning 8: buying a solution that you can modify is MUCH easier than perfecting a solution that you try to make yourself, and will probably save you lots of time and money in the long run

Advice for next year:

As far as the frame goes, if I was to do this all over again, I’d try to buy a frame like what we had here. That or VERY CLOSELY copy something that someone else has already built. There’s no reason to build it from scratch with no idea where you’re going. It made our lives so much more difficult than it should have. What we found is that once we could sit and roll around in the kart, tweaking it to perform well enough for our intents wasn’t very difficult. Trying to figure out where all the difficulties would be while designing it…. it’s nearly impossible. Don’t get stuck in that, instead leverage what others have done so you don’t have to waste the time they already spent designing it!

So the major recommendation from this is that at the end of the day, as long as it holds together, it won’t really affect the race that much. We’re not actually formula 1 racing after all. Instead, spending the time and effort on the drive train, or Electronics.

Those will be for later, I’ll try to write those up and go a bit more in depth now that we’ve covered some of the untold history that’s been going on for such a long time. The drive train I’ll write about first, then the electronics.

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