[piersdad]

Electric commuter car design



As I watch the huge number of new designs come out I wonder if they have actually lost the plot.
Artistic, streamlined, fast, slow, and darn site ugly etc none really practical as a mass commuter car.
If we look at the race car of 100 years ago and look at what they have today.

It is obvious today that fat tires, space frames, and totally enclosed passenger space were the way to go, but not 100 years ago.

So what do we want today in a dedicated commuter car that needs only get to the city speed limit of 50 km to 60 km/h and 2 people to the 60 km daily commute.
It need not be the family car as it would only be used by the worker of the family and the other car can be any that suits the family situation.

It has to be safe and with the racecars they have what I call deflection safety where components like wheels etc are sacrificed to protect the driver.
VW had this with a solid metal central frame and it tended in a head on crash to push the car to one side allowing the mudguard and wheel to deflect the crash.
I have not seen a VW with a direct head on crunch. Always a sideswipe.

So the chassis of an electric car has to have substantial beams or construction in the front that allows approaching solid objects to deflect the cars front from the passengers.
In the 1970s a research team used foam filled alloy box or shapes as part of a car and tested them to destruction.
The result was a huge amount of energy adsorption for the weight and size of the foam filled light alloy components.
An ideal aerodynamic front for any car which becomes a bumper as well.

The battery box then would be the main object to have in front
( batteries are cheaper, can be insured, but dead humans are difficult to replace)

So a solid battery box with a foam filled impact streamlining front nose cone.

This should not be fiberglass as this is both heavy and brittle so at least a alloy foam filled box . The alloy having crunching energy adsorbing ability.
Behind the battery is the passenger’s compartment.
Now who wants to crawl down to the level of a snake and wriggle into a super slim car?
No we need to approach the car and lift a gull wing door that enables one to walk into the car with dignity even with a child or carry cot in arms.
The next thing is the holding of the passenger in place by the seat belts.
These should have a attachment that has some limited give so that the passenger in a crash is decelerated slower than the car.
The car will be a total mess after a crash but the passengers are more important

These are the obvious things in their design and to date only one, near impossible to make , design has a walk in door.
All seem to be artistic and good looking or practical and darned ugly.

My own design from 1978 has all the features I mentioned.
Is made from 3 sheets of alloy
And tubular frame
It is pleasant to look at but the design could be better looking with combinations of different materials.
Alloy where best used.
Fiberglass where prettiness is needed.
Steel or alloy box section or tube where strength is needed.
So here is my original design

And here is the sketch of the newer chassis we never got to produce as we went on then to make an electric truck and all the buyers wanted a 2 seat electric commuter
Oh well we all make mistakes
.


this is an approximate drawing of the layout of the production car chassis
not a very good drawing as made from memory of 30 years ago but the general layout is shown

The use of a foam filled front and the batteries behind it meant most of the cars weight was in front of the passengers and adsorbed a crash energy
so with a air bag system in a modern version there would be a viable car suitable for today’s traffic

mobility scooters copied car design 100 years ago and still, believe it or not, all have the stupid tiller steering and no bonnet.

Lets hope that electric cars do not follow gas car designs and fail horribly in their practicality.

 

[TomA]

I'm not so sold on your assessment of modern vehicles.

Especially in crashworthiness and passenger protection, their performance is quite remarkable. That's the result of serious engineering, because safety sells and will justify the expenditure, and there's no substitute for an OEM's resources there.

Modern cars are also superb at sealing out wind and water, and lasting a long time. Again, those are things a solo designer or small engineering team with limited resources can never hope to replicate. Ever been in a gullwing kit car in a rainstorm? Name me one that doesn't leak. Even Ferraris (308, 412, 456) that cost a ton of money leak air and water because they just aren't up to the engineering standards the public now rightly expects in a $15k economy sedan. Its an ugly little secret you don't see written about in car magazines very often- many cool expensive cars leak, rust and have major wear issues.

If you want pretty one-off or bespoke EV design, expect big compromises in safety, durability, sealing and ergonomic performance. If you want quality in those areas, buy a Toyota Yaris or Nissan Cube and convert it to electric power. You won't be able to build a better chassis, period.

Beyond that, I guess I just don't understand what you mean by "Lets hope that electric cars do not follow gas car designs and fail horribly in their practicality..."when your average small late model sedan is actually a triumph of practicality, particularly for the money.

Just my opinion, I suppose...

TomA

 

[piersdad]

thanks for the feed back
if we combine the latest in car design with a more sensible layout we might get a car that is very safe cheap and reliable

how do you protect a driver if the battery weight in in the rear or under the seat the sensible place is in the front.

i see what you mean about gull wings leaking but there are some simple solution to that and to hinge the door at a slight angle across the top
this makes the water proofing almost the same as the sunroof designs we now have on vans etc

there will always be a market for the super slim--super fast--extra luxury electric car but they will only just equal the costs or excede the same in a fuel car.
and appeal to the rich and famous.

the every day folks car has to be different and simple
even if the entire car is stamped from a sheet of metal and put together with robots the layout should definately have the batteries in the front.

so i welcome comments on this

 

[sunworksco]

With Doppler/Radar accident avoidance systems,there is no longer a need to drive around in Sherman Tanks!
Give me an Indy race car CF cockpit and a www.alulight.com epoxy-bonded/rivet screw/chassis,
pin-drive/center-lock wheels and I would be happy!
Regards,
John

 

[piersdad]

With Doppler/Radar accident avoidance systems,there is no longer a need to drive around in Sherman Tanks!
Give me an Indy race car CF cockpit and a www.alulight.com epoxy-bonded/rivet screw/chassis,
pin-drive/center-lock wheels and I would be happy

exactly what i mean there are some fantastic new materials
the foam filled nose cone i used in the above car took about 15 minutes to make and with a can of hard fill foam was finished in 1 hour.
it had the lightness and impact resistance as well as cheapness.

as for the 4wd tanks that drive around.
in my city they are 1 in every 7 vehicles on the road here.
none ever seem to have driven off road

the indy car tech needs to be applied cheaply to the commutor car
where safety and lightness and cheapness can be combined.

i still shudder when an electric car design copies a golf cart or a lamborgini
nether is a candidate for a everyday safe commutor

many of the ev convertions put the battery in the bonnet on top of the motor but the fronts of these cars were designed for a petrol motor gearbox so they have to compromise.
the ideal is 2 motorised wheels in the rear, with the battery in the front.
this makes the structure of the front very much simpler as well the rear wheel motors will make the rear chassis a lot simpler.

what do they say KISS (keep it simple stupid)
thanks for the feed back

 

[sunworksco]

www.fiberforge.com has made the CF process inexpensive and production speed capabilities vastly improved.
http://www.youtube.com/watch?v=GPldvWbOQS0
Regards,
John

 

[piersdad]

thanks for the links there is some terrific materials out there
if my car was built from fibreforge materials it would be the same weight
my car weighed 300 lbs with out batteries

whew when the utube guy hit the moulded bowl of carbonfibre and it rang like a bell i was simply astounded at its strength .

too late for me but if i had that material 30 years ago and a set of modern brushless motorised wheels who knows what may have happened

 

[TomA]

the ideal is 2 motorised wheels in the rear, with the battery in the front.

You may believe that, but its just a choice among many possible compromises. Configuration is far less important than execution. It just isn't as simple as "these wheels should be powered," and "the battery should go here."

In the Solectria Sunrise, for example, the batteries are lengthwise in a central tunnel that runs most of the chassis. That's pretty ideal, too...

Over & out,

TomA

 

[piersdad]

the central tunnel was tried out in my NEEV electric truck ( we built 9 )

http://www.storydad.com/forum/index.php/topic,130.0.html

the rear deck gave very good access to the batteries but a central tunnel
would encroach on the available space for the passengers in a commutor car.

The morris mini did away with the centre transmission tunnel and see how
much room that added to the interior.

so a battery in the front and even a golf cart sort of standard transmision in
the rear would be great
or even a single wheel in the rear like the morgan cycle car

 

[sunworksco]

I'm designing my reverse trike off of the Palatov race car and suspension.I'm using Alulight aluminum foam panels.It will weigh 800lbs. with batteries included.I'm using Ducati 1098 wheel hub design for all 3 uprights with the Brembo brakes.It will be front-wheel-drive with Honda LSD inner components with custom case.Using the 1098 rear single-sided swingarm.
Regards,
John

 

[piersdad]

love it
some one else that thinks out side of the box.
good luck and i hope the tech details dont stop you

 

[sunworksco]

I have them all sorted out .Have been designing this trike with some of the most brilliant engineers in the world of EV.Dennis Palatov is building the custom suspension with the Ducati uprights.I will be using the AC-50 BL motor with Lithium batteries from ThunderStruck-EV.
The wheels are CF http://www.blackstonetek.com/
Using Michelin motorbike touring tires.
Regards,
John

 

[piersdad]

good luck
i wish i had more support 30 years ago but the biggest computors then filled a room and all communication was by snail mail or midnight phone calls to the other side of the world.
so now all i can do is hope some one will produce a really practicle commutor car

 

[sunworksco]

BTW,I love Morgans!
Regards,
John

 

[piersdad]

me too morgans were the practicle tricycle.
and th cars were way ahead of their time
i made an adult push tricycle with steerable/king pinned front wheels
and it was the most stable adult trike you could ride.
you could at speed even lean into the turn and run of two wheels.
it was a real fun trike

 

[Woodsmith]

I love Morgans too, for lots of reasons.

I have read this thread a couple of times and I am not sure I follow you in terms of the 'really practical commuter car'.

Your solutions wouldn't suit my commuter needs for example.
I have to drive 30 miles each way at 70mph almost door to door. Though I travel alone (ignoring other's suggestions that I need a 'honey' seat) I also need to carry bags and tools so a single seater with large luggage space is better.
I am sure I am not alone in having a different cummuting need to what you have considered.
The 'really practical' aspect seems to apply only to what you think a commuter should be doing. It is a bit like environmentalist who think all people can take the bus and work within 5 miles of home carrying no more then a small bag and commute at convenient and flexible times.

The gull wing door doesn't work for many people, many parking spaces or low height garages would pose problems foro access. Sliding doors might be better.

You say 'All seem to be artistic and good looking or practical and darned ugly.' but that is very subjective and not really meaningful.

What is 'darned ugly' to one person is beautiful to another, what is practical to one is pretty useless to another.

The battery location is important. Insisting that they would/should be in the front with rear wheel drive isn't good. They need to be in the right place for the design and that could be anywhere.
If an electric car was mass produced then the batteries would be located to make manufacture easiest. If the batteries were swappable then they would be in an easily accessible position for swapping. That could be at the back, under the floor, in a central tunnel accessible from one end, anywhere that works.

There is no one size fits all and making big bold statements suggesting that everyone else (large manufacturers? Small manufacturers? DIYers?) have got it wrong despite all their market research is, perhaps, a little arrogant, maybe?

However, good on you for trying to find a solution that fits your needs and having developed some designs and solutions.

 

[piersdad]

perhaps, a little arrogant, maybe?

not really i have left this car design in the cupboard for 30 years and waited and waited for a more complete approach to EV design.

all seem to build for a narrow customer base.

on our car we hinged the doors 1/2 way and on an angle across the roof and when opened they protruded no more than the width of the human body into the parking area.
then when it was open the driver/passenger was able to easily step/walk into the car and sit down.(5ft 8inch stud)

we tried it with many different people from a child to a 90 year old frail lady and all thought it was the best access they had tried to get into a car.
no more squatting sliding just walk in and sit with dignity.

The basic layout with even a standard tube/box/rail -whatever chassis with perhaps easily lengthened or shortened to suit different peoples desires or designs

i say the battery shoud be in the front as it becoms easily serviced and the space above it could also be luggage space if there is enough room.

have to drive 30 miles each way at 70mph almost door to door.

why i suggest 30 to 40 mph is that up to this speed the aerodynamics are not so important and above this you have to slim the car down with batteries down the centre or packed where you can.

i shudder when a rich guy says "my car can do 250 mph"
ok the speed limit in my country is 62 mph so where will he use this car with out breaking the law except off road.

so by sort of rabble rousing and getting feed back here people will really look at what is needed and not follow a design that has evolved for a heavy motor and light weght fuel tank.

here is a link to what i wrote about our design in 1978

http://www.storydad.com/forum/index.php/topic,529.0.html

The following are the features of this car

1 steering column folds out of the way to allow ease of entry and exit
2 steering column also acts as hand brake and power disconnect for the batteries.
3controlls and indicating lights are on the steering wheel.
4 steering wheel has rose colored mirror for the ladies (Ahemm!)
5 dash board is of soft alloy to adsorb energy in case of crash
6 when the gull wing door is open it acts as shelter in case of rain.

etc

so not to be arrogant just want good back feed from users as if nothing is done about what is really needed the basic design of EVs could get in a time warp like mobility scooters have (they still all have tiller steering from copying cars of 1901)
so thanks for your post it is well recieved

 

[Woodsmith]

Your ideas are good and reasonable for the applications that you envisaged and a lot of effort seems to have gone into resolving issues that were/are important.

However, 35 years have passed and although many of your specifications are still sound, and that shows the worth of your designs, not everything has remained the same.

The 'arrogance' I refer to may be a bit too strong a word but you make some strong statements in reference to modern car design and what is practical but I don't see the evidence to support it.
I only see your opinion worded to subjectively support your design solution.

Much of your original post I would agree with, back in the 1970s. I probably thought as much myself back then. But I have learnt a great deal and adjusted my views a lot since then.

What I know is that there is no 'one size fits all' solution.
What is right for me isn't going to be right for all others.

Do you still think a rose coloured mirror on the steering wheel 'for the ladies' is a good idea worthy of note in the future of personal transport?
I'm not sure your front suspension design would be safe at higher urban speeds with modern tyres, I can see the body swinging out and moving the CoG to a point where the front axle tips (Ralph Nader and the Corvair springs to mind here).
A leaning body shoud really lean into the bend rather then swing out of it.


So, respectfully considering your experience and time served in designing your vehicle, what new ideas are you able to share with us given the use of modern cars for conversion and modern designs for scratch building?

I'm truly sorry if I seem harsh but you sound a little like me 30 years ago when I thought I had all the answers. You have offered a 35 year old view and personal opinion, show us your current view and opinion.

 

[piersdad]

no offence taken
your comments are exactly what i want to be aired
and the rose colored mirror was just a joke then
but i re wrote exactly what was on the gestetner page written way back then.
a serious discussion about the design of future EVs has to be aired to stop designs that were exquisitly designed for one purpose are not inappropiately used just because they are available.
our pendulum suspension worked very well up to 50 km/h but may not work well say on a race track.
i tried the similar suspension design on a mobility scooter and it was absolutley fantastic.
i was able to take a roadside 100mm curb at full speed (12km)on an angle and apart from a noise there was no indication i have actually crossed a curb
when in switzerland i noticed that one railway station had an exclusive EV park with power points and the commutors arrived from the nearby villages from up to 30 or more km away parked their cars and rapid transport into Zuric.
every one of those commutors would have chosen a 50 km/h 50 km+ range EV.
the future trend in cities is to have rapid transport and parking with in a radius of 30 approx KM of the residential areas some thing i predicted 30 years ago.
this makes best use of evs and best use of rapid transport.
so the commutor gets the more leasurly trip to the station and company to the city.
however there is always the trades person that has to commute with lots of luggage so the more substantial EV is needed here.

so even when i had the conzept car, i also had a hybrid electric sports car for long distance demos of the car.
so even i needed 2 sorts of vehicle to suit my style

 

[henson2491]

The space frame concept is good! An "exoskeleton" design can be strong and light at the same time. My approach is to fill the spaces between the tubes with urethane foam and then do an overlay of epoxy and fiberglass. This requires a lot of hand finishing but it is easily accomplished in my home garage. This picture is a mock-up with a 15KWh battery arrangement. The 35KWh approach takes up all the available space outside the passenger compartment. I would need a small tunnel for the wiring from front to rear. My approach uses a single speed (11:1) reduction gearbox so no shifting! (No clutch. no transmission!) Simple and efficient! Street legal in California if homebuilt. With a total curb weight of about 1600 pounds acceleration should be OK while still allowing for a top speed of 70 mph or so. Any thoughts?