Electrathon America Forum

Members Login
Username 
 
Password 
    Remember Me  
Post Info TOPIC: Prone... Why is it a No-Go?


Member

Status: Offline
Posts: 13
Date:
Prone... Why is it a No-Go?
Permalink  
 


So I just randomly thought it might be cool to make an electrathon vehicle with a prone driving position. Several possible advantages come up with some different challenges to overcome. However, I read carefully through the core rule book to see if it was legal. As it turns out... title "Driving Position" on page 11 under rule #22 says that only upright reclining positions are allowed and arms and legs must remain inside the vehicle at all times.

I understand the arms and legs rule but why not prone or "face forward" designs? We have ATVs and motorcycles/trikes in the real world racing environment that have face forward driving positions.

The only main concern I may see with having a face forward design is keeping the users head/neck safe during serious collisions; which, to me, doesn't seem like a hard thing to accomplish. With a 5 point belt (strap-able by the driver) and a structure around the helmet that should be easy enough to accomplish. A sufficient shell/structure would still be required of course, but that still doesn't negate the possibility of a safe prone position vehicle.

What do you guys have to say about this? What are the main reasons behind this rule?

Thanks,

Zach



__________________
I Love Electric Vehicles!
Ron


Veteran Member

Status: Offline
Posts: 52
Date:
Permalink  
 

The rule was written in this way for safety (and keeping insurance company happy)

Besides, what would you hope to accomplish with a "head forward" design? smaller frontal area?

out here in the northwest there are some cars that are "reclining" so far that the drivers are nearly lying down...
if they were "face forward" they "MIGHT" be 1 1/2 to 2 inches shorter...

in my opinion there is not enough improvement in aerodynamics to warrant the extra weight to make a "safe" face forward car...

the only other reason I can think of is to lower the center of gravity of the car...

these same "reclining driver" cars I spoke of are also at the "lowest" that the rules allow for "body to ground" distance, their stated reason is

"to lower the center of gravity so we can corner faster, and for less frontal area for lower drag"

well I'll give them the lower drag... (they are 1/2 as tall as my car)

BUT:

my car has over 3 inches ground clearance and I regularly corner as fast or faster than they do...

yes they are more aerodynamic and probably would conserve batteries better than my car IF we had perfectly flat tracks...

but we don't... and in my opinion the "scraping" they do on the pavement on bumpy tracks costs them as much power as my lack of aerodynamics.. 

 as far as I have seen driving smoothly is more efficient.... unless of course you have the best of BOTH worlds...

a good SMOOTH driver AND a great aerodynamic car (Hi Shannon... yes I'm talking about you...   You too Zane...) that is "tough to beat" combination..

 

however the main reason for me would be....

  I don't want my face to be the first part of my body to be at the "point of impact" in a crash...

Ron J

Safety marshal
Tech inspector
driver car #13
Northwest Division



-- Edited by Ron on Saturday 12th of March 2016 06:44:35 AM

__________________


Senior Member

Status: Offline
Posts: 163
Date:
Permalink  
 

I think another problem is you can't put your harness on and off

__________________

Electrathon Of Tampa Bay executive board member



Veteran Member

Status: Offline
Posts: 35
Date:
Permalink  
 

All to do with crush zones. In an accident, you're most likely travelling forwards with speed at the moment of impact, so the frame will take the brunt of the force. Although you don't realise it, the frame always deforms under impacts; it's just whether it stays deformed (plastic deformation) or returns (elastic deformation).

Gladly enough in a reclined position, when/if the chassis deforms, your knees, ankles and hips have a good capacity to flex and allow things in the frame to bend and absorb the impact energy; likely up to half a meter if things are very, very dire; you'll definitely have minor injuries though! If the first point of contact is the face, unfortunately that same amount of deflection would have your head at about your kidneys... likely less ideal.

Also, if you use pedals for control, pressing on the brake will push your weight forward as the vehicle decelerates, meaning you'll come away from the pedal, so you'll need to push harder on the pedal, making the problem more pronounced. Steering would be the same issue, where your hands would pull away from the steering. The feedback of a feet-first position makes controls intuitive.
To meet Regulation 9.5, you need to be able to decelerate by an average of just over 0.5g. In a recumbent position, your harness and seat take most of the load and the rest is like doing a squat. But in a prone orientation, your whole body wants to come forward and press your face against the front of the car.

Bikes and ATVs are quite different; in an accident, you evacuate the vehicle and therefore use a race suit and armour to be able to slide along the track and away from the vehicle. Ours you're contained and you can't avoid the energy of the vehicle, so it's quite a different predicament.

There's only been one wheeled sport I know of that it's allowed; it's been used to good effect in International Human Powered Vehicle racing at Battle Mountain, but that's on closed roads looking for top average speed where they have absolutely minimal control requirements, brake very slowly at the end of the course and have virtually nothing to strike in an accident. And of course the Skeleton in the Winter Olympics allows it too... but they're totally crazy.



-- Edited by Brendan_Smith on Tuesday 15th of March 2016 05:59:48 AM

__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.