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Sustainable Vehicle

Sharkboat

Sharkboat

100 mW
Joined
Jun 3, 2011
Messages
37
Location
Binghamton, NY
I am a senior mechanical engineer working on my senior project. The goal of this project is to make a sustainable vehicle. The second goal of this project is to create "a perspective shifting machine."-liveforphysics.
Parts:
Frame: KMX Tornado 2011 Kit: 750
Motor: 3220-F 4 turn $800
Reduction: DaVinci drive $585
Controller: HV160 ice2 programed for ev use
RC Cycle Analyst 125
150A Deltec Shunt 25
Chainring Adapter 130mm 83
48T Origin 8 Chainring (used) 20
Rear Wheel w/ 45mm Rim (used) $100.00
Maxxis Hookworm 20" Tire $23.00
Gen1 CA Mount (used) $30.00
KMX Drive System Mount $153.95
Magura Twist Throttle (used) $20.00
Bullet Connectors $6.00
QTubes 20x1.75-2.125 tube $6.00
KMC Premium Z510HX Chain $16.00
Chainring Bolts $5.00

I still have to buy 4, 5000mAh 35C 6s lipo, 116 each, wired 2 in series and 2 in parallel.
hobbyking quatro 4X6s charger
powersupply for charger: unknown
battery holder possibly http://www.mouser.com/ProductDetail/Hammond-Manufacturing/1550JBK/?qs=sGAEpiMZZMtIfCzob2ABWciHj3xn3Rd3

This vehicle will have a top speed of approximately 41 mph. and have an efficiency of close to 20 wh/mi at 30 mph. I will post any useful data from the cycle analyst.

I plan on making a tailbox to reduce the aerodynamic drag. Our budget for this project is very small (I am buying all the electronic components myself) We have $100 allocated for the tailbox. My original plan was to make one out of a zotefoam fiberglass composite, shaped to look like the Nocom tail fairing. As a backup plan, i might make the fairing out of coroplast, following this tutorial: http://recumbents.com/wisil/tailbox/barracudatailbox.htm#Tailbox%20version%203

more pictures and video to come.
 
Looks good.

I am glad to see people building useable vehicles with this technology. I tend to use my bikes for fun. But, I know that we need to move toward true ultra light weight EVs. This is where the future is at and projects like this, with the intent this project has, moves our world a little closer to that ideal.

Matt
 
After talking to an EE, i realized that the battery charger i was thinking about buying would take a long time to charge my batteries. Obviously you get what you pay for, at only $100. Does anyone have any suggestions for a reasonably priced charger, hopefully one that comes with a power supply?
 
I would recommend the Methods LVC/HVC "complete lipo protection" system (see the for-sale section) and then bulk charging using something like an adjustable-voltage current-limiting lab power supply, or other "bulk charger". Lab PSUs like big old Sorensons and the like can be periodically be found used for relatively cheap, if you don't need one that's small or light. A number of server PSUs like some of the Hewlett-Packard units can be used or modified for use as bulk chargers. Fechter has a current limiter (available in the for-sale section also) that's adaptable for many PSUs, though it may require some reverse-engineering and probing around in the PSU to find the right place to hook it in.

Then you can use either separate single-cell chargers (or the adjustable lab PSU) to balance single-cells or cell-groups when you find them getting too far out of balance.

Or use the regular "RC Lipo" type balancing chargers for that purpose, or Battery Medics or similar. You likely won't need to balance all that often anyway, if not discharging the pack(s) deeply, once you have tested the packs you get and weeded out the bad ones.


You can skip the "protection kit" if you frequently monitor the packs for balance and have pre-tested them at various levels of charge (SOC) and discharge rates, so you know how much sag you might get at various loads, and then also set the LVC in your setup to cut or reduce throttle somewhere above the absolute minimum low voltage for your pack. The CA can do that part, since you're already getting one.

I am currently running bikes using a manual monitoring of hte CA for that cutoff, but I have the Methods stuff to install (I just have to wire it in). If I didn't mind paying close attention to my packs/etc. for experimental data reasons anyway, I would prefer to just let the system monitor it and let me know when it's time to stop.
 
I'm very excited to see this build unfold!

Amberwolf is right on with charging. If you're just looking for an at-home unit, the Mastech HY5020E lab supply is a nice pick, and is somewhat portable, you can also likely find more affordable units used.

For high power charging that's portable, it's hard to beat the Zivan NG1 with custom programming (we can probably get a hold of a lightly used unit at a better price for you). They can do 1000W (sub 1 hour charging on a 15Ah pack), and are very portable and efficient. Balancing can be handled with battery medic handheld 6S balancers (http://www.hobbyking.com/hobbyking/store/__10328__Hobby_King_Battery_Medic_System_6S.html), but if the pack is kept above 42V, it'll very likely never need balancing.

11NG1-2.jpg


Also, on another note, I'd suggest the Turnigy 20C packs (http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=16207) over the 35C's, and go with 6 or 8 instead of 4. You'll reduce voltage sag by increasing your capacity, while saving money on batteries. The vast majority of our trike systems are equipped with 25Ah (10 packs), which is a nice balance between weight, range, and fast charge times. Of course, you can always add more packs later, but you generally don't want to mix C-ratings, so your best bet will be the 20C's from the get go.

Let me know if you have any questions, have fun with the build.

-Tommy
 
I bought 4 of the 25c batteries, i realized that 35c was unnecessary. I plan on buying more batteries as money becomes available. I'm working on a college student budget. Right now I'm working on the aerodynamic portion of the design. As soon as the batteries arrive I will have it wired up and running. I'm also working on a roll cage for the vehicle. Our original plan for our project was to enter it into the Human Powered Vehicle Challenge, with the electronics removed. Because we no longer have a sponsor, we won't be competing. We already designed the roll cage, so we are putting it on the vehicle any way.

We are going to do coast down testing to hopefully determine the coefficient of drag and rolling resistance. One test with and without the fairing should show how much of a difference it makes.
 
The batteries arrived today :) The chargers will take a few more days because they are being shipped over seas. I bought 2 really cheap battery chargers that I plan on upgrading later on. I'm almost done with the aerodynamic design aspect. I am going to do all the research needed to wire up everything today. Hopefully I wont have to ask any n00b questions.

is there an easy way to get around the 512mb image size limit?
 

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is there an easy way to get around the 512mb image size limit?
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My guess is if you host them yourself there isnt a size limit?


Where are you getting a picture that is 512MB! :shock:

Very interested to see how this goes, looks great so far!!!

Edit: Miles your too fast :lol:
 
what range are you hoping to get?

with 44v10ah pack the joy of this powerful drive wont last long.. you will need to watch the V as at 6KW the battery voltage under load [sag] will go down significantly...
 
I can only afford 10ah at the moment, but i plan on increasing the size as much as i can. It's also a lot easier to mount only 4 batteries on the frame right now.

I can't wait to take this thing off-roading, hit a few jumps, and get some nice video.

Unfortunately e-bikes are illegal in new york. The tail fairing will cover up the motor, but not the sound. I think if i'm discrete and keep it under 20mph, no one will bother me. I looked up the history of the laws against ebikes and it seems that the bill to pass them keeps getting proposed, and always ends up dying or lost in a "research committee"

I'll try to find a nice 250 Watt sticker for the Astro 3220 ;)

My dream would be to make a vehicle like this http://cyclingexperiences.com/my-cycles-2/my-cycles/catrike-700/

with extra large disk breaks and a windwrap fairing
 
at my school, the two other automotive projects are the supermileage and mini baja. I want to get better fuel economy than the supermileage and have faster off road times than the baja. The supermileage car only got a few hundred miles to the gallon last year, so that won't be a problem. The baja car is limited to 10 hp. I have easily 9000 watts on tap and well over half the weight.

I would also love to get the local high school involved and try to convince them to start an electric vehicle program. If you want to change people's minds, it's better to start young.
 
Sharkboat said:
Unfortunately e-bikes are illegal in new york. The tail fairing will cover up the motor, but not the sound. I think if i'm discrete and keep it under 20mph, no one will bother me. I looked up the history of the laws against ebikes and it seems that the bill to pass them keeps getting proposed, and always ends up dying or lost in a "research committee"
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Where in NY are you?

The tailbox seems a bit tall in the picture. How far above the drivers head is it?
 
Sharkboat said:
Unfortunately e-bikes are illegal in new york. The tail fairing will cover up the motor, but not the sound. I think if i'm discrete and keep it under 20mph, no one will bother me. I looked up the history of the laws against ebikes and it seems that the bill to pass them keeps getting proposed, and always ends up dying or lost in a "research committee"
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Good to see engineering students getting involved in e-vehicle projects. Several engineering professors and I advised a team of students up build up a BugE and compare the BugE to conventional transportation. See
http://planetforward.org/idea/tennessee-students-engineer-eco-vehicle-that-drives-for-pennies/
for details. You should get your advisor to look into the EPA P3 program for funding. We just proposed another project to fund three teams of undergraduate engineering students and high school students to build ebikes and compete for performance. More details if we get it funded.

Anyway, I want to encourage you to think about other issues in addition to what can be built. A very significant part (the most significant part?) of our transportation issues in the States can't be solved with traditional engineering alone, at least not without civil engineers. Poor urban planning and traffic design as well as public perception may be bigger problems. I really like the vehicle you are building but it is not legally a bike nor a motorcycle/scooter in most of the states in the US. Car companies have conducted surveys over and over again and the biggest impediment to a truly game-changing personal transportation option is probably the lack of public acceptance of the additional risk and lack of versatility, convenience and weather-protection. The students that worked with me on the project noted above concluded this over and over; people think a small electric vehicle is really cool but when it comes down to it, they won't buy them in any significant numbers, yet.

I have sort of concluded that in the short run at least, the e-bike is the sweet spot for alternative transportation. It is on the interface of essentially unregulated transportation and a full-on licensed vehicle. My ebike gets me to work within about 5-10 minutes of my car driving time, I can ride off-road on bike trails and it integrates well with runners and pedalers. As long as I am judicious, I can even get away with powered speeds over the legal limit with some pseudo-pedaling. The less something looks like a bike, the more attention it will get from law enforcement (the cool projects I see here not withstanding).

So keep working hard. Change will be slow but with bright interested young people, hopefully it will be smooth.
 
Thanks for the advice. The wood in the picture is a mock roll cage, that will be built out of chromoly tubing. The fairing isn't shown, and will be smaller than the roll cage. The roll cage was designed for our project, because we were originally going to the human powered vehicle competition. I'm not sure if the roll cage will be of much help, especially since we don't have the budget for a safety harness. kind of defeats the point.

Those are all important concerns to think about. Another big once that i heard when asking people's opinions about different small electric vehicles was their perception of being unsafe in the event of a collision, due to their size.

Ugh, just ran into a problem with the EEs. They said their part of the project can't handle more than about 20 amps. After the semester ends, I'll be able to push this thing to the max, but for now, it is a giant beast with no balls :(
 
I live near Albany, but I'm going to school at Binghamton University. I might be moving out to Colorado for the summer. the 3220 could go on a mountain bike after this project ends.
 
Sharkboat said:
Ugh, just ran into a problem with the EEs. They said their part of the project can't handle more than about 20 amps. After the semester ends, I'll be able to push this thing to the max, but for now, it is a giant beast with no balls :(
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20 amps... That is a good one! I think most EE departments don't have a good practical experience with power so 20 amps would seem like a lot to them unless they have other practical experience. Keep up the good work though! You young folks will have to be smarter than my generation. We were sitting on top of a mountain of black gold. Cheap plentiful energy was a given for engineering purposes. It may turn out to be one of the most important engineering challenges of your future though.

Have PM'ed details about the P3 program.
 
Finally got the vehicle up and running. It is so much fun. It's nasty weather here, but I'll get a video as soon as possible. The gearing is a little slow now. I might switch from a 13 tooth chromoly freewheel to a 16 tooth White Industries. I'm also considering making a custom heat sink out of copper for later on when i over power it.
 
Sharkboat said:
Finally got the vehicle up and running. It is so much fun. It's nasty weather here, but I'll get a video as soon as possible. The gearing is a little slow now. I might switch from a 13 tooth chromoly freewheel to a 16 tooth White Industries. I'm also considering making a custom heat sink out of copper for later on when i over power it.
Click to expand...

Great!! anymore pics?
 
I dont have a camera with me now, but ill take some as soon as i can. Drove it home today from campus, about 5 miles. It is way faster than by car! The best part is i can park it in the senior lab for charging, right in the center of campus. Beats searching around for a parking spot.

On campus I was driving it a little too fast for people to think it was a bike and the fairing isn't on it yet, so the motor was visible. Got pulled over by the police. Didn't even get a warning. They told me that it needed to be registered, but didn't know very much about the laws concerning this type of vehicle. Too bad NY laws are horrible. Can't even register it as a neighborhood electric vehicle. As long as i am careful on campus and dont show off, i should have no problems driving it to school and back. I found a route on the back roads, all 30 mph zones.

Froze my hands off and it started to hail, i was having so much fun i couldn't care.
 
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