Years of my babbling about vehicle design: http://www.eternalmachinery.com/ecar/
- includes a video loop panning around this car.
This is more simple and fun than my previous plans. I guess I want to show people that electric cars can be fun, to encourage them to switch. Plus, have a fun car, that I understand and can fix every last bit of. And enjoy the process of making it.
I'd appreciate all kinds of feedback.
I realize this is an ambitious project, likely to take years. I'm planning to weld the frame myself, and I haven't even welded.
NetGain Warp 9 motor: $2,074 (just behind rear axle)
Soliton 1 controller, 1,000 amps continuous: $2,899 (behind rear axle)
48 160ah prismatic lithium cells, 144v = $9,627 (front, yellow block)
Lots more than I'd like to spend. I think I'll save buying those parts till the end.
Those three components plus the driver are positioned so that the weighted average of their locations is centered between the two axles. For 50:50 axle balance, therefore balanced steering at the limits of traction. (Passenger will bias the weight toward the rear. And of course there's all kinds of stuff I haven't accounted for.)
One of my higher priorities is being able to spin the tires. But I want to bolt the motor directly to a rear differential, so I'm a little concerned about having enough torque without a transmission.
Motor goes up to 5,000 RPM. The most reduction I've seen in a diff is 4.9:1, which works out to 96mph max, which sounds fine to me. Does that leave me enough torque to spin the tires from stopped? I'd prefer more gear reduction. 5.9:1 would give me a max of 80mph. I wonder how NetGear feels about doing different windings for more torque (more winds and fewer turns = more torque).
has the same components (slightly smaller pack), can spin the tires, and will go 90 miles when babied. But has a transmission. But probably also weighs more?
I really don't want a front bumper, but that seems to be required by New Hampshire law. Although it looks like they can be very minimal, like a bit of 1" thick pipe
. I was thinking about putting bumpers on the fronts of the fenders, since the nose doesn't stick out past them. But I think it might be better to extend the body out past the fenders, and put something like 1" thick by 4" tall rubber across the front. I'd really like ideas here.
Looks like all New Hampshire law relevant to titling a car is here: http://www.gencourt.state.nh.us/rules/state_agencies/saf-c3200.html
I need to work out the suspension details (arm angles). I'm thinking dual wishbone, with push-rods to cantilevers to inboard coilovers (formula 1 style). I'd like to get the uprights / knuckles (and disc brakes) from a junk yard, but needing to attach fender supports might require fabricating them.
How should I do the windshield wiper? Windshield is an inconvenient shape. I could get the thing to rotate the right way with two rods attached at wider points at the base.
Which kind of welding should I use? For a square tube space frame. TIG is sexy, slow, and expensive. Stick... would probably work just fine?
I'm thinking of pivoting the hood and the canopy both just above where the firewall would be, between the driver and battery pack. Make the whole front end pivot up, for easy access.
I know I could really easily significantly improve the aerodynamics, especially at the front end. (I know about laminar vs. attached flow, and Sears-Haack bodies.) But... I keep coming up with stuff that's insanely difficult to make, or ugly. I like the way this one looks. Gives me shivers.
How does this have anything to do with a T-bucket? Take a T-bucket, remove the bucket / seating. Add tandem seating and a full length body. Add a roof. Replace Model T frame with space frame. Convert to electric. (I still need to lower the seating position because there's no-longer a drive shaft in the way.)
My last ancient thread
, never built anything.
I need to re-read that, lots of good stuff there.
Stuff in that thread was structurally complicated and efficient. My new one is structurally much simpler and more fun.
So much to learn.
I've been doing my modeling in blender, which is free. I wish solidworks wasn't $4,000.