vtsnowedin wrote: Of course if we get $10.00+ gas and 0.40/KWH electricity such a vehicle might get pressed into 90 percent of your driving, especially if it can be charged by your off grid roof top solar panels.
vtsnowedin wrote:It sounds like you are working yourself up to a Ford Lightning F-150 or one of it's competitors. If Biden gets half his proposed chargers installed cross country trips will be no problem.
vtsnowedin wrote:The light , evolved golf cart or hightec. trike of the future might run in the $4000 to $12,000 range and be an addition to your garage not your primary or foul weather vehicle.
Of course if we get $10.00+ gas and 0.40/KWH electricity such a vehicle might get pressed into 90 percent of your driving, especially if it can be charged by your off grid roof top solar panels.
The_Toecutter wrote:I have in mind building a "car" that is suitable for a single person, that is so light and efficient that energy costs, no matter what they might become, will remain a non-issue. So efficient, you could put a bicycle drivetrain in it and with the motor disabled you could pedal it to near-highway speeds(at least on flat ground), or while using the motor, cruise highway speeds with a small amount of pedaling akin in effort to walking accounting for nearly 1/3 of the amount of the energy used to move the vehicle. And it will be fast enough to out-accelerate vehicles with 15-20x its horsepower with the motor in use.
Best of all, my vehicle concept uses a lot of low-tech and dumb-tech.
AdamB wrote:
So...those of us who want to put 4 people in an EV, heat it and cool it, winter and summer, and don't care that instead of spending $0.50/charge we spend $1.50/charge for all this convenience, are you going to build one for us?
Or will your design stay with something a lazy bicyclist would love, who upon impact with a run of the mill 4000# SUV will die heroically in the name of efficieny uber alles? You haven't mentioned much about how many airbags your better design will have? I would really like to survive even a moderate collision in my EV, and I imagine most users might feel the same.
The_Toecutter wrote: Can you imagine what 0-120 mph acceleration in 4 seconds would be like!?
AdamB wrote:Yes. But only because Elon built a damn fast version of the S, which my wife's boss owns, and it can't accelerate that hard. 0-120 in 4 seconds, which is what, 1.35G's of acceleration? That is going to require something you haven't mentioned yet, and that is traction. Strap a 800HP Ferrari to 4 bicycle tires and that 800HP ain't going much of anywhere, regardless of the power to weight ratio.
Alfred Tennyson wrote:We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.
vtsnowedin wrote:As toe-Cutter's concept car is refined and commercialized would not AI safety features like automatic emergency breaking be employed to the degree that the need for airbags and other weighty safety features is reduced?
I would not be a fan of any pedaling requirement
but for those that want it would it be possible to turn a generator by pedaling to charge the battery pack with the car either in motion or stopped at say a traffic light?
Would the in-out efficiency of that be less then the direct pedal to drive sprocket of a bicycle?
I have to doubt Toe-Cutters 100 miles per KWH but as he doesn't provide the weight of the vehicle or say how much pedaling contributed to the figure it remains plausible.
Consider the Tesla Model S with a curb weight of 4883 pounds and a 1200 pound battery pack holding 80KWH at full charge . It uses 30 kwh per 100 miles or 0.3/mile.
That battery pack consists of 16 modules each weighing 75 lbs and holding 5.3KWHs.
If you built a car around two of those modules keeping the curb weight to battery weight ratio the same you would get an ultra light 610 lb vehicle with the same 300+/-range as the model S. Hopefully for a lot less then the S's $80K price tag.
theluckycountry wrote:An ICE motorcycle like mine has 200Hp, can carry a decent amount of groceries and achieves around 6L per 100km. That's like $20 a week in gas for hundreds of km in pleasurable trouble free motoring.
Why would you bother making some niche trike for commuting to the store aside from your own love of bicycle projects?
Sure you can fit a roll cage but that wont be of much use when a 5 ton truck rolls over you. Some would say my liter bike is just as dangerous but it has the power, and more importantly, the handling (maneuverability) and braking to get me out of those sort of scrapes.
The_Toecutter wrote: Having a motor in each wheel with instantaneous slip detection will allow the tires to be used for everything they are worth, so for the vehicle's parameters regarding weight distribution, mass, torque curve, ect. I'll get the maximum possible acceleration from that setup, whatever it happens to be. It's just that theoretically, with perfect traction, the math does suggest 0-60 mph under 2 seconds with that sort of wild and crazy setup.
The_Toecutter wrote:And having such low drag, that acceleration would carry over into the second half of that delta given how little power would be needed to maintain the max speed for that delta relative to the power available.
The_ToeCutter wrote:So basically, a 100-120 lb "car" may be able to be made to reliably output close to 150 horsepower, without shit breaking.
Tanada wrote:Seems to me a lot of folks are making the perfect goal the enemy of what you could do right now. For example Lit Motors has had their concept out there for about a decade now, it had great reviews and so far has not had a noticeable impact.
The_Toecutter wrote:Mine brakes and maneuvers just fine. It's more agile than any car I've driven(I have a Triumph GT6 EV conversion and have driven a V8 Mazda Miata conversion), and it will soon have more than enough power to accelerate away from trouble once I perform the upgrades I intend. I'm soon looking at the possibility of 0-60 mph < 7 seconds using a cheap $250 Chinese hub motor that weighs a grand total of 16 lbs, if I can get sufficient traction.
AdamB wrote:Elon does something similar, but a motor for each wheel isn't required if you just split a single motors output and modulate it independently.
I can see the branding already though, "ToeCutter Motors".
theluckycountry wrote:I think it's a good project you have there, What sort of tires do you run?
I like the Bafang mid-mount motor design as it allows for steep climbing without straining the motor. My 750W with it's big rear cluster will literally climb trees!
Of course these motors put a lot of strain on the chain, which are designed for human power levels, 250W, 500W max?
I envisage a day, possibly, when these sort of bikes might be a practical alternative to petrol vehicles, but that wouldn't happen until petrol vanishes or is severely rationed.
The_Toecutter wrote:vtsnowedin wrote:As toe-Cutter's concept car is refined and commercialized would not AI safety features like automatic emergency breaking be employed to the degree that the need for airbags and other weighty safety features is reduced?
I'm not sure they'd be of much help in my vehicle, especially against a collision caused by a much older/heavier vehicle that doesn't have these things. It might take 20 years for the current vehicle fleet to turn over before these items are commonplace enough to matter to the safety of the trike operator as well.I would not be a fan of any pedaling requirement
I designed mine with a functional bicycle drivetrain in order to get around licensing/insurance/registration requirements. Thus far it has worked.
I plan to eventually build a car version without a bicycle drivetrain.but for those that want it would it be possible to turn a generator by pedaling to charge the battery pack with the car either in motion or stopped at say a traffic light?
Generators add significant weight, and they are inefficient compared to a bicycle drivetrain. Further, you cannot run the vehicle directly off of pedaling if the bike is set up for your pedaling to run a generator. If the battery runs dead, you're stranded. I like the redundancy of two drive systems. I can pedal mine with the EV drivetrain completely disabled because I retained a bicycle drivetrain, and once I install a Schlumpf drive, I'll have gearing to allow my pedaling to account for some of the thrust to move at 100+ mph after doing the upgrade I'm planning on.Would the in-out efficiency of that be less then the direct pedal to drive sprocket of a bicycle?
Greatly so, plus the penalty of added mass. A bicycle drivetrain is about 95-98% efficient. A generator, typically around 50-80%.I have to doubt Toe-Cutters 100 miles per KWH but as he doesn't provide the weight of the vehicle or say how much pedaling contributed to the figure it remains plausible.
That figure is at 35 mph cruising speeds and light pedaling. The vehicle weighs 90 lbs. But it is the aerodynamics, and moreso than the weight, that allows this efficiency. With zero pedaling, using throttle-only, it can hold 30 mph with 400W drawn from the battery, or about 0.013 kWh/mi, but with ~150W of pedaling that drops to about 0.007 kWh/mi.
This body shell is nowhere near as efficient as the next one will be. My unmotorized Milan SL can do 30 mph on about 150W of pedaling, and I bought it to reverse engineer to improve my own design. Without a motor, I can almost reach 50 mph in the Milan on flat ground.
With the sort of aerodynamic slipperiness I'm after combined with low weight, it is theoretically possible to build a vehicle that can cruise 70 mph using only 0.015-0.020 kWh/mi, and not even need the motor on at all to do 30 mph on flat ground with light pedaling. I'm not there yet with my prototype, even though it is usable at much lower speeds than 70 mph on a daily basis, with over 65,000 miles on it now.Consider the Tesla Model S with a curb weight of 4883 pounds and a 1200 pound battery pack holding 80KWH at full charge . It uses 30 kwh per 100 miles or 0.3/mile.
That battery pack consists of 16 modules each weighing 75 lbs and holding 5.3KWHs.
If you built a car around two of those modules keeping the curb weight to battery weight ratio the same you would get an ultra light 610 lb vehicle with the same 300+/-range as the model S. Hopefully for a lot less then the S's $80K price tag.
You also need to consider aerodynamics matter greatly more than weight at the highway speeds the Tesla's range is obtained at. It is CdA that is the determinant of how far you go for a given battery(CdA = drag coefficient multiplied by cross-sectional area).
vtsnowedin wrote:
So the vehicle weighs just ninety pounds? Does that include the battery?
How about your own mass? After all it is the curb weight plus the passenger or passengers plus the cargo/ groceries that has to be lifted over the next hill plus the rolling resistance.
Could not the drive motor or one of them in a multi motor set up be capable of being both a motor and generator as needed to not add any additional weight to the vehicle? They are very much alike in construction and might just need the right chip in the control center.
I can envision being at zero battery, out in the boondocks, on a dark night, far from the end of any extension cord and just pedaling away while watching a two hour movie to get me going again and off to grandma's house.
If you go back to the Tesla figures which some would say are the state of the art at present, you could calculate that you could double the weight of your light vehicle to 1250 pounds and cut it's range to 150 miles without making it's drag coefficients any better or worse.
You could probably make a vehicle at that weight safe enough for you to put your wife and children in it.
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