Front Underrun or Underride Guards

NHTSA has been lying to the American public since 1992.

Most victims are killed in front underride crashes.

NHTSA’s lies about front underride are used to make other underride guards not practical.

If you walk or ride a bike in America it is just about side underride guards! False.

Front underrides are only high speed occurrences due to the closing speed of both the car and truck. False.

Additive speeds are so high they are not survivable. False.

NTSB – 60% of pedestrian fatalities are to the front of the truck.

NTSB – 31% of cyclist fatalities are to the front of the truck while 40% are to the right side of the truck.

 

When we crash test guards at 30 to 35 mph we get guards for 50 years that perform at 30 to 35 mph.

The FHWA Office of Safety considers that a 100 km/h (62.2 mph) crash test is representative of worst case run-off-road crashes. We agree, real world fatal crashes happen on 50 mph roadways and between 50 and 60 mph. If we test at real world crash speeds we will get underride protection that performs at these speeds.

Scorpion Truck Mounted Attenuator – Saving Lives (English) Youtube Video (Warning – upsetting crash pictures and video) Protects government employees at higher speeds than guards to protect the general public do. Extending guards 900 mm or about 3 feet increases the effective crash speed protection to about 67 mph or 107 km/h.

 

Chalmers Car-to-Truck Frontal Crash Compatibility

Increasing the length of the HC (HoneyComb shaped front nose underrun guard)
increases the critical impact speed

To 95 km/h (59 mph) with a 300 mm – length HC structure (+27%)
To 102 km/h (63 mph) with a 600 mm – length HC structure (+36%)
To 107 km/h (67 mph) with a 900 mm – length HC structure (+43%)

 

ECF Position on Safer HGV Cabs
NHTSA – THE HEAVY GOODS VEHICLE AGGRESSIVITY INDEX
fka – Concept Design of a Crash Management System for Heavy Goods Vehicles
fka – Design of a Tractor for Optimised Safety and Fuel Consumption
Volvo European Accident Research and Safety Report 2013

 

A LOOK AT THE NHTSA MINIMALLY COMPLIANT UNDERRIDE GUARD AT IMPACT SPEEDS ABOVE 30 MPH – John E. Tomassoni

“Comment: It is clear that offset impacts will result in greater underride magnitudes than in centric impacts, all else being the same. Underride is also expected to increase with increasing offset. But impacting vehicle rotation will also occur in offset impacts. This will, of course, depend upon the amount of offset and the interacting structural properties. It is very likely that the occupant responses will be less than with centric impacts, but this will be only if the occupant head and torso are not contacted by the intruding structure. Injury measures, however, will be greater for the occupant on the impacted side. It is possible that vehicle rotation can be either clockwise or counterclockwise depending upon the strengths of the interacting vehicle front structure and the guard. If the guard offset strength is less than the engaged portion of the car crush strength then the guard will deform and may cause the car to rotate with its front deflecting somewhat away from the centerline. On the other hand, if the. guard offset strength is greater than the car crush strength, then car rotation will be in the opposite direction where its rear end will displace away from the centerline. See offset impact data contained in Refs 5, 6 and 8 which indicate that a guard total strength of greater than 45,000 pounds is needed for adequate offset impact protection. It is expected that certain offset conditions could result in car rotation such that the passenger compartment may beneficially avoid intrusion entirely. The performance of the MCG has not yet been demonstrated by test for offset or angle impacts.”

 

NRC-CNRC: Side Guards for Trucks and Trailers Phase 1: Background Investigation

“In Canadian urban collisions involving heavy vehicles, bicyclists and pedestrians, the front of the heavy vehicle (front, right front and left front) was the initial point of impact in 42.9% of the cases for bicyclist fatalities and 45.8% of the cases for pedestrian fatalities. The right side of the heavy vehicle (right middle, right rear and entire right side) was the initial point of impact in approximately 28.5% of cases for bicyclist fatalities and 6.3% of cases for pedestrian fatalities.”

“The front of the vehicle was the initial point of impact in 48.5% of the cases for bicyclist fatalities and 71.6% of the cases for pedestrian fatalities in the US heavy truck-VRU collisions. The right side of the vehicle was the initial point of impact in approximately 22.5% of cases for bicyclist fatalities and 7.9% of cases for pedestrian fatalities.”

 

Monash MUARC Front Energy absorbing barrier Recommendations from:
REVIEW OF TRUCK SAFETY:STAGE 1: FRONTAL, SIDE AND REAR UNDERRUN PROTECTION

A stroke equal to the maximum possible without leading to impacts on the steering wheels or axle and preferably 500 to 600mm.

A road clearance of not more than 350mm.

Full width out to the outer edge of the tyres or mudguards.

An energy absorption capacity of 100kJ.

A frontal projection of at least 300mm to provide a buffer space in impacts with the sides of cars, and hence reduce the opportunity for direct head and body contact.

Curved at the ends to reduce concentrated loads being applied in angled collisions.

A layer of progressive crush material applied to hard surfaces.

Progressive crush of the energy absorbing barrier which starts off “soft” for impacts with unprotected road users and the side of cars, and increases progressively to suit frontal impacts with a range of cars.

Residual strength after full energy absorption, as set out below:

P1  400 Kn       P2  300 Kn        P3  200 Kn

 

ECE R93 The European Front Underrun Protection Device Regulation PDF

Download (PDF, 869KB)

 

EU Directive 2005 66 Front Protection and Bull Bars

Download (PDF, 1.26MB)

 

Results from VC-COMPAT

The analysis revealed that about 11 % of the fatally and 30 % of the seriously injured car occupants could be saved if trucks were equipped with energy absorbing front underrun protection systems (e.a. FUPS) instead of rigid FUPS, and that approximately 57 % of the fatalities and 67 % of seriously injured could be prevented from their injures due to improved rear underrun protection systems (RUPS). The report closes up with the major conclusion that improving rear underrun protection systems show a comparable reduction potential as for improving front underrun protection systems.

“Plans are underway to extend the front of the truck 300mm to 500mm or more to create a crash zone or deformable soft nose that would absorb crash energy and might reduce serious injuries and fatalities another 10% from the current standard on trucks with energy absorbing guards, and survivable speeds would be increased to 80 to 90 km/h (56 mph).”

“the energy absorbing capability and capacity of passenger car front structures has improved to such an extend that impact speeds up to 64 – 75 km/h (Approx. 40 mph to 47 mph) may well be survivable for passenger car occupants in collision with rigid FUPs.”

 

pedestrian nosecone smallNosecone designed to be integrated into the truck body and underride
prevention systems that will divert bikes and pedestrians at low speeds and
divert cars at higher speeds, low-weight and low-cost were design factors.

 

APROSYS – “It is shown that the risk for injuries to head and lower extremities may be reduced by up to 97% at impact velocities of up to 40 km/h. (25 mph)” Big city bike riders, do we have your attention now!

Front low-speed crashes with VRU (Vulnerable Road Users) are quite survivable with proper design. Unlike NHTSA’s poo-pooing of front underrun protection, victims are save-able and it is indeed worth doing.

 

AP SP2 WS on VRU Protection for HGV smallSven Faßbender, IKA, Aachen, Germany

 

In total, 90 front-end geometries were tested numerically and finally a shape was found not only decreasing the risk for run-over, but decreasing the severity of the secondary and primary impact too. The risk for run-over decreased by more than 85% when fitting the “nosecone” to the HGV. Finally the nose-cone was designed in detail in a CAD-environment and then tested in a FE-code (by hemispherical impactors).
Faßbender stressed, that the nose cone is not intended to be retro-fitted to HGV, but should be integrated in future truck designs. Beside of improved partner-protection, the nose-cone might contribute to improved aerodynamics and less fuel-consumption.

 

Download (PDF, 3.41MB)

 

We now have crash evidence that low and high-speed crashes into curved underride guards or nosecones can deflect cars or VRU ie. bikes and pedestrians. The crash energy instead of being absorbed by the car and victims is deflected into a different direction and is dissipated harmlessly in the friction of the car spinning on the road. NHTSA performed crash tests in 1992 at around 30 mph showing the car could be spun away from the truck using aluminum honeycomb guards with curved ends. NHTSA stopped all future research by stating the car might hit another car. Remember the disappearance of the safety cars with giant bumpers and electric cars that disappeared. If NHTSA has an outcome that is unfavorable to industry they just poo-poo it or make it disappear.

NHTSA “High speed crashes are un-survivable so high-speed guards make no sense and are not practical” or something similar. End of discussion. They forget most car crashes into trucks are on high-speed roadways, or more likely they fail to share this sad fact. End of discussion. Do not try to manufacture working guards in front, back, or rear of trucks. It is not practical, crashes are not survivable anyways.

Safety groups are planning an underride conference in the coming months and excluding front underride. Why is this important, remember, high-speed crashes are not survivable. You cannot exclude front underride. Bike riders remember, front underride is more fixable than side underride and is just as important. Most fatal car crashes are to the front of the truck. We must talk about front underride, we can divide roadways while were at it.

“The size of an energy-absorbing truck front structure directly correlates to the survivable closing speed between car and truck in head-on collisions (e.g. 75 km/h (46 mph) survivable closing-speed requires a 400 mm long energy-absorbing structure, 90 km/h (56 mph), requires 800 mm (2.6 feet)).” From Volvo Report

Look at the rounded nose cones shape and how it extends two to three feet to the front of the truck. Now imagine we can place light-weight plastic pistons in that area to absorb energy maybe to 90 km/h or 56 mph or higher. Now imagine the curved shape deflecting the vehicle so it does not have the full force of the impact. Imagine your bike being deflected away from the truck rather than underneath or the impact softened by the softened nose cone.

 

Underride Network position on high-speed crash tests:

NHTSA crash tests new cars to rate their safety in crashes and publishes performance based on a star system thru their NCAP rating for new cars.  You might buy a car that is 5 star crash rated that passed with flying colors the 35 mph offset crash test. Why are trucks exempted? Undo influence from lobbyists?

When we crash test guards at 30 to 35 mph we get guards for 50 years that perform at 30 to 35 mph. When you try something over and over and over again and get a negative result, why would you continue this activity. If we crash test guards at high speeds perhaps we will see guards that perform at high speeds. The FHWA tests crash attenuators in 62.2 mph crash tests (Real World Crash Speeds) and attenuators protect cars and trucks in crashes at 62.2 mph and more!

The FHWA Office of Safety considers that a 100 km/h (62.2 mph) crash test is representative of worst case run-off-road crashes. We agree, real world fatal crashes happen on 50 mph roadways and between 50 and 60 mph. If we test at real world crash speeds we will get underride protection that performs at these speeds. When guards fail tests at real world speeds manufacturers will finally feel public and political pressure to increase crash effectiveness. We must see real world tests of guards at 50 and 62.2 mph such as tests at FHWA for crash attenuators. We must use more extensive crash test criteria such as those used in the AASHTO Manual for Assessing Safety Hardware (MASH). MASH tests cars to 100 km/h or 62.2 mph and big trucks at 80 km/h or 50 mph. MASH tests crash attenuators at various speeds and we should do the same for underride guards to give the public a real world picture of their safety.

The Underride Network supports a similar criteria for underride guard crash tests as those submitted by Prof. Raphael Grzebieta and (Adj) Associate Professor George Rechnitzer and Transport and Road Safety (TARS) Research Centre in Australia based on the criteria used for MASH crash tests in the AASHTO Manual. We would submit requiring multiple speed tests to include real world crash speeds and would not limit extension of guards to increase crush or stroke distance to increase guards effective speed while diminishing deceleration forces. Tests might be performed at 44 mph and 50 mph and 62.2 mph to test minimally compliant guards in low-speed test and using higher speed tests to monitor performance at real world crash speeds. We support testing for Practical Worst Case (PWC) scenario crashes that happen in the real world just as MASH includes PWC in it’s crash test series. We must include tests of offset controlled after crash direction of vehicle spin or VRU (Vulnerable Road User or bikes and pedestrians) after crash spin to assess high-speed crash avoidance for cars and prevention of running over VRU users in frontal crashes. John E. Tomassoni “It is expected that certain offset conditions could result in car rotation such that the passenger compartment may beneficially avoid intrusion entirely”. WE would encourage annual NCAP type testing of truck and trailer underride guards to encourage industry improvement of guards on an annual basis such as crash performance of cars improves on an annual basis using publication of the results of NCAP tests for cars to increase sales of better performing products.

 

Chalmers Car-to-Truck Frontal Crash Compatibility

Increasing the length of the HC (HoneyComb shaped front nose underrun guard) increases the critical impact speed

To 95 km/h (59 mph) with a 300 mm – length HC structure (+27%)
To 102 km/h (63 mph) with a 600 mm – length HC structure (+36%)
To 107 km/h (67 mph) with a 900 mm – length HC structure (+43%)