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Electric Reverse Trikes. Ideas, Rants, Collaboration?
- Thread starter todayican2
- Start date
michaelplogue
10 kW
(already posted in my "Hardknock motorcycle" thread, but thought it would be good to post it here in this trike discussion thread)
Although I'm still moving ahead with my development of an ICE trike, I decided to play around with my design to see how hard it would be to adapt it to a pure EV - with a rear-chain drive motor.
In order to distribute the weight of the batteries better, I've moved the driver's position to the rear. In this configuration, I was able to fit in enough of the larger prismatic LiFePO4 cells to get 120V 120AH capacity. There's plenty of room for pretty much any size motor, so this could potentially be a real rocket!
I'm not a big fan of enclosed-cabin trikes, but figured I'd give it a whirl. Didn't come out too bad. Would have to work in a pivot at the front of the windshield - rotating it and the roof forward for passenger access. I think I'd still prefer an open cabin design - just my personal tastes.......
This is the latest version of my ICE model for reference so you can see a similar design without a roof......
Although I'm still moving ahead with my development of an ICE trike, I decided to play around with my design to see how hard it would be to adapt it to a pure EV - with a rear-chain drive motor.
In order to distribute the weight of the batteries better, I've moved the driver's position to the rear. In this configuration, I was able to fit in enough of the larger prismatic LiFePO4 cells to get 120V 120AH capacity. There's plenty of room for pretty much any size motor, so this could potentially be a real rocket!
I'm not a big fan of enclosed-cabin trikes, but figured I'd give it a whirl. Didn't come out too bad. Would have to work in a pivot at the front of the windshield - rotating it and the roof forward for passenger access. I think I'd still prefer an open cabin design - just my personal tastes.......
This is the latest version of my ICE model for reference so you can see a similar design without a roof......
These are great renderings, and nice designs. The CAD really gives you a huge advantage in packaging and working out details!
Two factors that contribute to stability are worth considering carefully. The first is weight distribution, the second is "effective half-tread" or track width as applied to a trike.
Weight distribution is easier for the EV. Ideally, you want 1/3 of the weight on each wheel. Your ICE trike appears quite tail heavy. You could place batteries ahead of the front axle of the EV editions to balance them better. With the CAD, you can fool around with it and really dial it in. That's cool.
Where that cg winds up (and particularly how low it is) will largely determine how narrow your front axle can safely be. Like me, you are pursuing a narrow track, which will take some doing to keep stable. The best primer on the subject is in Walter Korff's book "Designing Tomorrow's Cars" from 1980. Korff patented the reverse-trike-made-from-a-motorcycle-in-back design (called the DuoDelta) that has been copied so many times since. There are also some good resources at the RQ Riley home page about trike stability.
I especially love the way you can use curved tubes with your CAD designs. I wonder how the classic small-tube "birdcage" concept would look and perform if treated to this CAD-enabled bending of the tubes. It could go from "birdcage" to "birdnest" and really be something sensational, but I digress...
Anyway, very tidy work. I sure would like to follow along and see how something like this goes from renderings to fabrication. I understand how your software can assist in the process of producing cut, bent tubes, brackets and so forth, but can it also help in jigging them together- like making temporary bulkheads, formers or the like? Could you even do up a companion chassis jig in CAD, that presumably would be made of straight pieces with simpler alignment issues, and then fabricate that first? Its a very interesting process to me, and even in the design stage, it sure does produce beautiful, finished work.
Good show,
TomA
Two factors that contribute to stability are worth considering carefully. The first is weight distribution, the second is "effective half-tread" or track width as applied to a trike.
Weight distribution is easier for the EV. Ideally, you want 1/3 of the weight on each wheel. Your ICE trike appears quite tail heavy. You could place batteries ahead of the front axle of the EV editions to balance them better. With the CAD, you can fool around with it and really dial it in. That's cool.
Where that cg winds up (and particularly how low it is) will largely determine how narrow your front axle can safely be. Like me, you are pursuing a narrow track, which will take some doing to keep stable. The best primer on the subject is in Walter Korff's book "Designing Tomorrow's Cars" from 1980. Korff patented the reverse-trike-made-from-a-motorcycle-in-back design (called the DuoDelta) that has been copied so many times since. There are also some good resources at the RQ Riley home page about trike stability.
I especially love the way you can use curved tubes with your CAD designs. I wonder how the classic small-tube "birdcage" concept would look and perform if treated to this CAD-enabled bending of the tubes. It could go from "birdcage" to "birdnest" and really be something sensational, but I digress...
Anyway, very tidy work. I sure would like to follow along and see how something like this goes from renderings to fabrication. I understand how your software can assist in the process of producing cut, bent tubes, brackets and so forth, but can it also help in jigging them together- like making temporary bulkheads, formers or the like? Could you even do up a companion chassis jig in CAD, that presumably would be made of straight pieces with simpler alignment issues, and then fabricate that first? Its a very interesting process to me, and even in the design stage, it sure does produce beautiful, finished work.
Good show,
TomA
todayican2
100 W
- Joined
- Apr 22, 2009
- Messages
- 139
Good to be back! I built a new computer a while back and for the life of me could not find my damn password, hows the trike building going guys?
chaster
10 W
todayican2
100 W
- Joined
- Apr 22, 2009
- Messages
- 139
Very cool Chaster! whens the "skeleton drive"? 
bigmoose
1 MW
I scanned through your thread and didn't see any mention of the Shrike:
The home page is http://nortonshrike.com/shrike.htm
Dave Norton first built this IIRC, about 20 years ago. He has written an ASME paper on trike stability. I tried to find the paper in the open literature to no avail; but I bet an ASME member could get it.
I had exchanged correspondence with Dave once when he was still in CA, but after the move to Oregon, he didn't return correspondence.
Dave's Shrike and his ASME paper may be of help. The cornering performance and stability of the design seem pretty good.
The home page is http://nortonshrike.com/shrike.htm
Dave Norton first built this IIRC, about 20 years ago. He has written an ASME paper on trike stability. I tried to find the paper in the open literature to no avail; but I bet an ASME member could get it.
I had exchanged correspondence with Dave once when he was still in CA, but after the move to Oregon, he didn't return correspondence.
Dave's Shrike and his ASME paper may be of help. The cornering performance and stability of the design seem pretty good.
chaster
10 W
todayican2 said:Very cool Chaster! whens the "skeleton drive"?
It'll be a while. We're pretty busy here with the xenoDisplay project, and the SPARC still needs a fair amount of work (installation of drive system and whatnot) before I can take her for a spin. I'll get her running with the tilt locked out (the vehicle is actually designed as a tilter, but the tilting system is somewhat unique, and I don't want to have DMV give me a hassle when I go to license it - so the tilt can be locked out and the vehicle steered like a standard car). Once that's sorted, and the vehicle is registered & licensed as a non-tilting trike, I'll begin work in earnest on the tilting system.
I'm going to try to blog regularly about the project on our site (or at least, in the forum on the site) instead of here on E-S. I frequent too many sites to keep all of them "up-to-date" with progress, so please stop by our site (or grab the RSS feed) if you're interested in progress. :wink:
Cheers!
Eric
Yes, the Shrike is cool, and one of the best sorted and documented RTs.
I don't think about it much as a starting point, though, because its a performance ICE machine with relatively low efficiency.
It gets 30-40mpg. Bodywork would improve that considerably, but its still a heavy muscle machine compared to where I'm headed.
For sure, though, the background RT vehicle considerations and methodology are impressive and useful, and I have to say this may be the safest light RT out there.
Its a great vehicle...
TomA
I don't think about it much as a starting point, though, because its a performance ICE machine with relatively low efficiency.
It gets 30-40mpg. Bodywork would improve that considerably, but its still a heavy muscle machine compared to where I'm headed.
For sure, though, the background RT vehicle considerations and methodology are impressive and useful, and I have to say this may be the safest light RT out there.
Its a great vehicle...
TomA
Just thought I'd add some designs to your discussions. Hunt around this a little. IT's EV based. You will find some ICE drives around in there as well.
http://sketchup.google.com/3dwarehouse/search?tags=detalidon
http://sketchup.google.com/3dwarehouse/search?tags=detalidon
Ok - so finally have read the whole thread and have time to properly write up. This thread has been a total delight as especially TomA's concept is very close to the ideas I have been spinning in my head.
My (current) idea is:
- As low windage and resistance as other parameters allow
- Fiberglass foam core shell with inner chromoly frames to share point loads and help crash safety.
My latest idea is to have shell made of two halves that are combined leaving opening in the front, around driver and in the rear. Subframe would be split to 3-4 pieces so that they can be inserted inside the combined shell and bolted up. (this doesn't sound too far from what was brought up earlier on this thread. Except I would probably steer away from CF except maybe as localized reinforcement. From what I have read using CF in wet layup is sort of a waste anyway. Foam core should help in crumbling in case of collision. One layer of kevlar would probably be feasible though to enhance impact strength.
- 50 mile range at higher cruising speeds or mixed city driving - with enough physical space reserved to later upgrade for a bigger pack if one so will.
- 6hp constant 15hp peak is around what I have been thinking but the acceleration might be pathetic.
- "outboard" front wheels to allow superior handling and narrow main body.
- Sketches are with 19" rims but aerodynamically that is probably a bad choice. Also motorcycle wheels are not designed for lateral forces so they might not hold up in hard swerves. I would assume the bigger the rim the bigger this issue is.
- custom double a-wishbone suspension. I have access to TIG and will start practicing soon. Spindles etc. probably from a quad. I do have a friend with quite well equipped machine shop but ebay parts are always cheaper than making anything.
-roadster configuration - rather big top opening for easier entry but probably a 'lid" around the driver kind of like on the mango velomobile. Alternate lid with canopy could be considered.
My biggest issues are the safety - in terms of visibility - I ride motorcycles so I understand that there are risks. However a small and low trike is even more invisible than a motorcycle yet not as powerful and nimble for getting away from trouble.
The visual design is very much work in process. The longer nose is for better head on collision safety. Front axle is probably way to front for any kind of sensible weight distribution - I weigh 200-210 lbs and I am 6'4" - not the smallest driver.
[youtube]WsfiDKmXi_k[/youtube]
I am working on somewhat easy setup in 3d-app to test different steering geometries. I can do it pretty well but I have to rebuild the rig every time the dimension change.
[youtube]emZuiUYTAfA[/youtube]
My (current) idea is:
- As low windage and resistance as other parameters allow
- Fiberglass foam core shell with inner chromoly frames to share point loads and help crash safety.
My latest idea is to have shell made of two halves that are combined leaving opening in the front, around driver and in the rear. Subframe would be split to 3-4 pieces so that they can be inserted inside the combined shell and bolted up. (this doesn't sound too far from what was brought up earlier on this thread. Except I would probably steer away from CF except maybe as localized reinforcement. From what I have read using CF in wet layup is sort of a waste anyway. Foam core should help in crumbling in case of collision. One layer of kevlar would probably be feasible though to enhance impact strength.
- 50 mile range at higher cruising speeds or mixed city driving - with enough physical space reserved to later upgrade for a bigger pack if one so will.
- 6hp constant 15hp peak is around what I have been thinking but the acceleration might be pathetic.
- "outboard" front wheels to allow superior handling and narrow main body.
- Sketches are with 19" rims but aerodynamically that is probably a bad choice. Also motorcycle wheels are not designed for lateral forces so they might not hold up in hard swerves. I would assume the bigger the rim the bigger this issue is.
- custom double a-wishbone suspension. I have access to TIG and will start practicing soon. Spindles etc. probably from a quad. I do have a friend with quite well equipped machine shop but ebay parts are always cheaper than making anything.
-roadster configuration - rather big top opening for easier entry but probably a 'lid" around the driver kind of like on the mango velomobile. Alternate lid with canopy could be considered.
My biggest issues are the safety - in terms of visibility - I ride motorcycles so I understand that there are risks. However a small and low trike is even more invisible than a motorcycle yet not as powerful and nimble for getting away from trouble.
The visual design is very much work in process. The longer nose is for better head on collision safety. Front axle is probably way to front for any kind of sensible weight distribution - I weigh 200-210 lbs and I am 6'4" - not the smallest driver.
[youtube]WsfiDKmXi_k[/youtube]
I am working on somewhat easy setup in 3d-app to test different steering geometries. I can do it pretty well but I have to rebuild the rig every time the dimension change.
[youtube]emZuiUYTAfA[/youtube]
I have been thinking about something like this, and doing some research I found something funny.
Although I'm sure almost everyone is already aware of the BugE, I'm wondering about this picture:
The "shock" looks an awful lot like a battery
On a serious note, I like the BugE. It seems reasonably priced, no unnecessary components. Where to improve, on this?
Although I'm sure almost everyone is already aware of the BugE, I'm wondering about this picture:
The "shock" looks an awful lot like a battery
On a serious note, I like the BugE. It seems reasonably priced, no unnecessary components. Where to improve, on this?
Kerosene:
Very interesting design. I'm curious to know what you think the gross weight of your vehicle will be. My WAG is about 600lbs, depending on how much steel, motor and batteries you are throwing at it.
Some notes:
1. Your Cg is probably too far rearward. Depends on the drive package you are using, but it looks like 50% or more of the weight will be on the rear wheel. Should be no more than about 35%.
2. I personally don't like steerable wheel pants, but that's just me (and maybe the ghosts of Alex Tremulis and Frank Lockhart, if you believe in such things) talking...
3. You're right about CF- not a good material in hand lay-ups. Absorbs too much resin. S-2 glass is a better choice for this construction technique. I may also reinforce with kevlar tape, in spots, but not carbon fabric.
4. "Superior handling" is going to be a major challenge with quad parts, and a skinny 19" front wheel/tire package. I'm using only the quad spindles and hubs. My a-arms are fabbed heim-jointed CrMo. I'm also using Wilwood brakes, custom wheels, scooter tires, buggy steering, air assisted shocks from a CB900 Honda motorcycle, and a custom snowmobile-based anti-roll bar.
5. I'm right there with you on visibility. It is the biggest road-use problem for a vehicle in this class. I think Doug Malewicki addressed it best with his California Commuter, putting all the lighting on a pylon up at the other drivers' eye level. He has apparently never had a collision with this setup. I'll probably do something very like it, and add some strobes and noise (air horns) so I can command attention.
6. Depending on where you are going to license your trike, there may be issues with ride height, seat height, motorcycle and quad (off-road) parts, lighting, etc. Do your homework.
7. At this weight, collision safety is a very difficult problem. 'Nuff said.
I'm really looking forward to following your build. I wish I had your CAD skills, but I'm old school (measuring and marking the garage floor, making models in wood and plastic, etc.) which has its rewards as well as its drawbacks. Anyway, welcome aboard!
Dozentrio:
The BugE is cool, and in fact several owners have significantly improved it with battery, motor, systems and aero upgrades. Personally, I want something lighter and faster.
AriLea:
WOW! I absolutely love your OSCSV1S-RWD Open Source Design. The exterior envelope is very similar to what I'm doing for my Moonray. If you want to collaborate on taking a shape like this, tweaking it up, transferring it from the screen into an assembly jig, and actually getting it on the road, let me know- especially if you're in or near New York.
TomA
Very interesting design. I'm curious to know what you think the gross weight of your vehicle will be. My WAG is about 600lbs, depending on how much steel, motor and batteries you are throwing at it.
Some notes:
1. Your Cg is probably too far rearward. Depends on the drive package you are using, but it looks like 50% or more of the weight will be on the rear wheel. Should be no more than about 35%.
2. I personally don't like steerable wheel pants, but that's just me (and maybe the ghosts of Alex Tremulis and Frank Lockhart, if you believe in such things) talking...
3. You're right about CF- not a good material in hand lay-ups. Absorbs too much resin. S-2 glass is a better choice for this construction technique. I may also reinforce with kevlar tape, in spots, but not carbon fabric.
4. "Superior handling" is going to be a major challenge with quad parts, and a skinny 19" front wheel/tire package. I'm using only the quad spindles and hubs. My a-arms are fabbed heim-jointed CrMo. I'm also using Wilwood brakes, custom wheels, scooter tires, buggy steering, air assisted shocks from a CB900 Honda motorcycle, and a custom snowmobile-based anti-roll bar.
5. I'm right there with you on visibility. It is the biggest road-use problem for a vehicle in this class. I think Doug Malewicki addressed it best with his California Commuter, putting all the lighting on a pylon up at the other drivers' eye level. He has apparently never had a collision with this setup. I'll probably do something very like it, and add some strobes and noise (air horns) so I can command attention.
6. Depending on where you are going to license your trike, there may be issues with ride height, seat height, motorcycle and quad (off-road) parts, lighting, etc. Do your homework.
7. At this weight, collision safety is a very difficult problem. 'Nuff said.
I'm really looking forward to following your build. I wish I had your CAD skills, but I'm old school (measuring and marking the garage floor, making models in wood and plastic, etc.) which has its rewards as well as its drawbacks. Anyway, welcome aboard!
Dozentrio:
The BugE is cool, and in fact several owners have significantly improved it with battery, motor, systems and aero upgrades. Personally, I want something lighter and faster.
AriLea:
WOW! I absolutely love your OSCSV1S-RWD Open Source Design. The exterior envelope is very similar to what I'm doing for my Moonray. If you want to collaborate on taking a shape like this, tweaking it up, transferring it from the screen into an assembly jig, and actually getting it on the road, let me know- especially if you're in or near New York.
TomA
chaster
10 W
TomA said:
I was thinking the same thing, but I notice that he doesn't show where his motor and some other heavy components are going. If he puts the motor up front (somehow) and/or move the batteries forward (stacking them up in the front half), the weight distribution might not be as bad as it appears..
With vacuum bagging, the amount of excess resin absorbed in any composite layup can be minimized. CF is no different than 'glass in this area. That said, CF is expensive but using judicious amounts at critical junctures where stiffness is called for is not a bad idea. Kevlar is really what most people probably want for body parts because people are usually wanting toughness more than stiffness for most body panels. Too bad Kevlar is just as expensive as CF...
I was with you all the way until you said "scooter tires"... Is your vehicle a tilting vehicle? Sounds like it is not. Scooter tires on a non-tilting vehicle are going to have VERY poor traction and handling.... All of your high quality suspension & braking components benefits will be nullified by scooter tires (IMHO)...
Yeah, me too on the visibility issue. I have been joking around with my friends that I will put LED Christmas Light strings all around my vehicle... The "TRON LIGHTCYCLE" effect... LOL..
Wow, lighter than the BugE? 225 lbs without batteries? Highway capable with cro-moly frame and full body?
That will be awesome! 
The SPARC XEV target weight is 700 lbs (with 150+ lbs of batteries), and I think that's pretty darn light... I can't wait to check it out! Eric
Time, Money, and other priorities, like 3 60' trees that fell on my house 3 weeks ago.
No excuses. I'm making progress, but I work slowly and pretty methodically. The plan is to be operational next spring. See my blog:
http://the-moonray.blogspot.com/
No excuses. I'm making progress, but I work slowly and pretty methodically. The plan is to be operational next spring. See my blog:
http://the-moonray.blogspot.com/
chaster said:
I'm not vacuum bagging in the traditional sense. Its too expensive, and requires tools and materials I don't have. I'll be using the "lovac" system pioneered by the Cozy Girrrls and others. My brother-in-law has a Long-EZ, and works on it, and he's a great source of home-built composite information. The amount of Kevlar reinforcement I'll be using will probably add only a modest cost to the project. In several different trials I've seen, S2 glass is just the best performing material overall for a project like this. Kevlar and CF cloths are sexier, but S-Glass with some Kevlar reinforcement is probably a better technical compromise for my purposes, and not simply because it is cheaper to do it that way. But, yes, cost is part of the compromise...
Yes, I think about this. My vehicle is not a tilting design. There are a few things to say:
1. I can always buy 10" car tires if the fattest scooter tires don't work out. If I can't tune my way into something acceptable, I'll punt and buy two Yokohama A008s, but...
2. I actually want the front end to push (understeer) relatively early. I'm using a rear wheel that probably can't take much side loading, so if the vehicle doesn't develop much in the way of lateral g forces before it pushes, that's probably better for me.
3. This isn't a roundy-round racer or even a sports machine. Its a super-efficiency runabout. Lateral forces are almost entirely avoidable, and I'm the only pilot it will have.
4. The scooter tires are going to be much lighter and more efficient than any car or trailer tire, and they are better matched to my GVW.
5. I'm going to have full adjustability of the caster, camber, toe, ackerman, spring, damping and anti-roll settings. By the time I'm through fooling around with all that, I will really know whether the scooter tires are workable or not.
Still, I hear you, Eric, but I'm going to try it...
TomA
chaster
10 W
TomA said:
Hey, the Cozy Girrrls site is one I hadn't seen before. Thanks for mentioning it! I hear you on the cost issues with vacuum bagging. For pieces that are tubular (like my A-pillars) I plan to use a method which is used by model Rocketry builders and CF bike builders (I have a CF recumbent bike project that I started with this technique, but put on hold because of the SPARC XEV project): the "Food Saver" bagger technique. Basically, you use a Food Saver which has the manual option (i.e. it has a button to control the vacuum pump instead of an automatic pressure sensor) and bag the piece in the food saver bags (which are limited in width, but can be quite long since the bags come in rolls). When you have the piece vacuum bagged down, you just use the Food Saver sealer to close the bag and let it dry. Works like a charm for long and relatively skinny pieces. For other body pieces that can't be bagged with this technique, I was planning on doing some experiments with "weight bagging" (my term, not anything official). The idea would be to take pieces of stretchable rubber/plastic bag and stretch them over a given large piece (with the necessary layers of release and absorber mat) and then hang weights at strategic locations to provide pressure on the piece to squeeze out the excess resin. Not sure it will work, but I thought it would be worth a try before turning to more expensive routes.
Good points. Particularly #1 and #3. Worse comes to worse, you can always swap the tires out for "regular" car tires. And since you're not trying to out handle a Porsche, I agree, understeer at the limit is a desirable thing.
Eric
michaelplogue
10 kW
TomA said:
Wow! That really sucks - sorry to hear that. Hope insurance is covering it.......
I haven't had any juice to think trikes or electricity lately.
But I did find this:
http://www.filestube.com/82a7e72037c9789503ea/details.html
"Racing and Sports Car Chassis Design, costin"
amazon link with reviews
http://www.amazon.com/Racing-Sports-Car-Chassis-Design/dp/0837602963
a pdf version of hard to get (100+ dollars if you find one) vehicle chassis design book. Very cool - well written and 60s high end is still pretty valid - physics hasn't changed.
But I did find this:
http://www.filestube.com/82a7e72037c9789503ea/details.html
"Racing and Sports Car Chassis Design, costin"
amazon link with reviews
http://www.amazon.com/Racing-Sports-Car-Chassis-Design/dp/0837602963
a pdf version of hard to get (100+ dollars if you find one) vehicle chassis design book. Very cool - well written and 60s high end is still pretty valid - physics hasn't changed.