looking to change front bumper again.. better approach angle

[NevadaZielmeister]

That bar is designed to be a crash bar. It's meant to lower the bumper height making it safer if we hit a pedestrian or a car. On my 14 it was decently attached.

This is EXACTLY correct. The auto manufacturers were required to follow the standards set forth to reduce injury to pedestrians upon impact. The idea being to allow the pedestrian to suffer reduced injuries to the head and lower extremities by using soft crash bars. That is probably why Jeep went to a slightly less reinforced "crash bar" so to allow the pedestrian to decelerate prior to hitting their head on the hood.

 

[jnabird333]

This is EXACTLY correct. The auto manufacturers were required to follow the standards set forth to reduce injury to pedestrians upon impact. The idea being to allow the pedestrian to suffer reduced injuries to the head and lower extremities by using soft crash bars. That is probably why Jeep went to a slightly less reinforced "crash bar" so to allow the pedestrian to decelerate prior to hitting their head on the hood.

The guy I talked to didn't mention squat about pedestrian safety and if he had I would waive the bull-shit flag. While the bar is not that strong, It's still strong enough to break a human bone easily. Furthermore, by the time this bar would be involved (and remember from the factory there is a plastic funnel on it) The pedestrian would already have some body part under a tire or be getting clobbered by the axle and steering parts. I can't see a single instance this bar would help with a low speed impact of anything. The crush cans and Tupperware bumper would be far more in play.

 

[Jk909]

+1^^^^^ what he said

 

[NevadaZielmeister]

The guy I talked to didn't mention squat about pedestrian safety and if he had I would waive the bull-shit flag. While the bar is not that strong, It's still strong enough to break a human bone easily. Furthermore, by the time this bar would be involved (and remember from the factory there is a plastic funnel on it) The pedestrian would already have some body part under a tire or be getting clobbered by the axle and steering parts. I can't see a single instance this bar would help with a low speed impact of anything. The crush cans and Tupperware bumper would be far more in play.

+1^^^^^ what he said

I understand how difficult the concept might be regarding crash safety. People hated airbags when they first came out, but eventually people learned to accept them. Pedestrian strikes are something the government is looking at.

But don't take my word for it, please review this:

https://en.wikipedia.org/wiki/Pedestrian_safety_through_vehicle_design

or here:

http://www.edmunds.com/car-safety/protecting-pedestrians-through-vehicle-design.html

And if you have a bunch a time, this one is a primary source on the subject:

http://www-nrd.nhtsa.dot.gov/pdf/esv/esv19/05-0105-O.pdf

Happy reading friends!!

 

[jnabird333]

I understand how difficult the concept might be regarding crash safety. People hated airbags when they first came out, but eventually people learned to accept them. Pedestrian strikes are something the government is looking at.

But don't take my word for it, please review this:

https://en.wikipedia.org/wiki/Pedestrian_safety_through_vehicle_design

or here:

http://www.edmunds.com/car-safety/protecting-pedestrians-through-vehicle-design.html

And if you have a bunch a time, this one is a primary source on the subject:

http://www-nrd.nhtsa.dot.gov/pdf/esv/esv19/05-0105-O.pdf

Happy reading friends!!

All these links prove is that you can use Google. You are missing my point that the bar in question is vastly behind the initial point of impact and not significantly low enough to help any of the factors written about in the links you provided. Especially when you consider the bar is covered with a plastic guard that would funnel a pedestrian UNDER the Jeep.

 

[NevadaZielmeister]

All these links prove is that you can use Google. You are missing my point that the bar in question is vastly behind the initial point of impact and not significantly low enough to help any of the factors written about in the links you provided. Especially when you consider the bar is covered with a plastic guard that would funnel a pedestrian UNDER the Jeep.

I am, by far, NOT an expert. So I am not explaining exactly how Jeep designed the bumper and why. I am only giving some possibilities as to why they designed the bumper this way or that. It is an interesting field and one I follow as a course of my employment. However, I have not hired an expert in this field because by the time we are looking at the damages to the pedestrian, it is already too late and usually liability is clear, that being completely on the driver.

I am not here to prove anything. Only to assist. Remember, we are talking about a STOCK jeep. Looking at stock Jeeps, the pedestrian would not get funneled underneath. They would be impacted right where the knee bends, then giving them a chance at a reduction of a femur fracture. Most vehicles have bumpers heights right where our knees are. And I agree, that deals more with bumper height. But making that bumper softer, with less reinforcement behind it, would give the pedestrian less acceleration of their head into the hood. If it was a slightly softer blow, then their head would not get up to speed as much, thus reducing the amount of force the head would have to endure when the pedestrians body lays over the head. I believe that the links went into this detail quite well.

Does that make sense? Maybe I am not explaining it correctly?

 

[jnabird333]

Does that make sense? Maybe I am not explaining it correctly?

Yes, but you are missing that everything you just said pertains to the factory bumper and not the bar we are talking about that the lower air-dam mounts to. This bar is too far back and tucked up to be a factor for a pedestrian strike.

The bar we are talking about is roughly located where the red circle is.... The Green arrow is the air-dam. See how it would actually push a person down and into the axle should they get under the point of impact (the bumper)?

 

[noroad]

I have the crawler concepts skinny stinger and like it!


(picture taken by Wayalife)

 

[NevadaZielmeister]

Yes, but you are missing that everything you just said pertains to the factory bumper and not the bar we are talking about that the lower air-dam mounts to. This bar is too far back and tucked up to be a factor for a pedestrian strike.

The bar we are talking about is roughly located where the red circle is.... The Green arrow is the air-dam. See how it would actually push a person down and into the axle should they get under the point of impact (the bumper)?

View attachment 161725

First off, awesome photo. I like it. However, I am not sure that the "crash bar" is that far back. I just could not find any other photos of the front of a Jeep torn down to show the exact placement. Maybe the "crash bar" has nothing to do with "crashing". The factory bumper, I agree, would take the brunt of the force imparted to the pedestrian. Maybe there is another reason for how Jeep set this up?

Anyone else?

But based on your photo, the pedestrian would never be pushed underneath. His/her center of gravity would be high, such that his/her hip would hit the grille and then the head would whip around and into the hood. There were some claims where I found hair of the victim in the windshield. I rarely had situations where the pedestrian went underneath a car. Those situations normally involved a child. (And those sucked.)

 

[jnabird333]

Well, here is another view of it on my Jeep. I may have been off by an inch or so but I retain my thoughts. Also my Poison Spyder Brawler Lite sits back farther than the stock bumper's crush-can bump outs but the bar still sits back and too high to effect a pedestrian strike.




Something else I will point out that is more on topic though is notice how close to the face of my tires the bar is. While I have rubbed the bar some, the Bumper itself is the determining factor in approach not the bar. Both could be easily avoided by slightly turning one tire into a rock as Eddie suggested.