Posts Tagged ‘forensic engineering’
Researchers from Stanford University are experimenting with a new technology that is aimed at reducing injury severity caused by bicycle helmets. Current bicycle helmet design consists of a hardened foam or plastic shell that covers the upper half of a rider’s skull and reduces the impact forces present during a head to ground impact. New helmet technology includes the use of inflatable air bladders that cover the head in a similar fashion to most traditional helmets. The inflatable air bladders, similar to automotive airbags, cushion the head during an impact with a pillow of air. Current testing by Stanford researchers has shown that airbag helmets can reduce head impact forces by as much as five to six times over forces present in impacts with traditional helmets. Most foam bicycle helmets have been shown to significantly reduce significant impacts, reducing the likelihood of cranial fractures, concussions, or other head injuries. Airbag helmets are a promising step in the direction of reducing such injuries even more.
Much of the current research done at Stanford consists of properly understanding the mechanics behind brain injuries due to impacts with the ground or other hard surfaces. Research into the damage to brain tissue has shown that concussions occur when brain cells stretch or twist torsionally. During an impact, the brain may collide with the side of the rider’s skull, causing a collision within the head between the skull wall and the brain itself. Energy is absorbed by the brain in severe impacts by the brain matter itself. Obviously damage to the brain can occur if the impact is severe enough. Helmets capable of reducing impact severity, such as the airbag helmet, are already hitting the market in some European countries.
One main potential drawback to the airbag helmet design as a mainstream product is due to the fact that an airbag helmet’s effectiveness at reducing injury is only as good as the amount of cushioning provided by the airbag. If the airbag is not properly inflated with high-pressure air prior to impact, the helmet becomes significantly less effective at absorbing impact forces. Proper inflation of the airbags is therefore extremely important. Current versions of airbag helmets are not consistently providing sufficient air pressure to the airbag, rendering the helmets less effective at preventing injury.
The future of airbag helmets will rely on more thorough testing of the helmets that are more representative of actual impacts. Current testing procedures do not effectively model the occupant’s head, neck, and associated mechanics thoroughly enough to gain proper testing data. Further testing and development of the airbag inflation devices is also necessary to create a product that ensures proper inflation and a more robust inflation rate.
from Science Daily
Federal regulators and the auto industry are taking a more lenient approach than safety advocates would like when it comes to phasing in automatic braking systems for passenger cars, according to records of their private negotiations. The technology automatically applies brakes to prevent or mitigate collisions, rather than waiting for the driver to react. While such systems are already available in dozens of car models, typically as a pricey option on higher-end vehicles, they should be standard in all new cars, according to safety advocates. But instead of mandating it, the government is trying to work out a voluntary agreement with automakers in hopes of getting it in cars more quickly.
The Associated Press has obtained the Meeting minutes from three of the meetings that NHTSA has held with automakers since October which show that the government is considering granting significant concessions. Records of the third negotiating session, on Nov. 12, show that automatic braking systems would be allowed that slow vehicles by as little as 5 mph before a collision. Furthermore, manufacturers may be allowed to exempt 5 percent of their vehicles from the standard with an additional exemption for models that manufacturers intend to phase out or redesign. The minutes don’t specify a model year by which the technology would have to be included in cars, but the group did decide that discussion of any deadline would begin with “the latest date submitted by any automaker” for when they would be ready to make the change.
Meeting participants included NHTSA, 16 automakers, two auto industry trade groups and the Insurance Institute for Highway Safety (the insurance industry’s safety research arm). Representatives from Transport Canada, the Canadian government’s auto safety regulator, also attended.
NHTSA estimates show that there are about 1.7 million rear-end crashes a year in the U.S., killing more than 200 people, injuring 400,000 others and costing about $47 billion annually. More than half of those crashes could be avoided or mitigated by automatic braking or systems that warn drivers of an impending collision. NHTSA announced last year that it will include automatic braking and other collision-avoidance technologies in its five-star safety rating program to encourage automakers to more widely adopt the technology.
In an unusually pointed criticism, the National Transportation Safety Board, which investigates accidents and makes safety recommendations, said in a report last year that “slow and insufficient action” by NHTSA to develop performance standards for automatic braking and collision warning systems and to require the technologies in cars and trucks “has contributed to the ongoing and unacceptable frequency of rear-end crashes.”
NHTSA released its latest crash data statistics in two separate publications.
The first is titled “Early Estimate of Motor Vehicle Traffic Fatalities for the First Nine Months (Jan-Sep) of 2015” . This document provides a “statistical projection of traffic fatalities for the first nine months of 2015.” The report estimates that 26,000 people lost their lives in motor vehicle traffic accidents in that time period. This is an estimated increase of 9.3% when compared to the same time period in 2014. During the first nine months of 2014, there were an estimated 23,796 deaths.
The second document is titled simply “Quick Facts 2014 (DOT HS 812 234).” The purpose of this document is to provide a quick reference sheet covering the most commonly asked questions relating to motor vehicle traffic accidents and fatalities.
In a letter to Google’s Chris Urmson, the director of the company’s self-driving car project, the National Highway Traffic Safety Administration (NHTSA) concludes that it would consider the company’s self-driving vehicles (SDVs) as having a driver under federal regulations, despite being controlled by a computer. This means that self-driving or autonomous vehicles are a step closer to America’s highways. NHTSA posted a detailed response on its Web site.
Google’s SDVs are fully autonomous, meaning that the operations of these vehicles are controlled exclusively by a self-driving system (SDS), according to the search giant. The SDS is an artificial-intelligence (AI) driver, which is a computer designed into the motor vehicle itself that controls all aspects of driving by perceiving its environment and responding to it.
Now, according to the NHTSA, that’s enough to qualify for driving.
“NHTSA will interpret ‘driver’ in the context of Google’s described motor vehicle design as referring to the (self-driving system), and not to any of the vehicle occupants,” according to the NHTSA, which was released this week. “We agree with Google its (self-driving car) will not have a ‘driver’ in the traditional sense that vehicles have had drivers during the last more than one hundred years.”
Google’s cars are designed to perform all safety-critical driving functions and monitor roadway conditions for an entire trip.
“The next question is whether and how Google could certify that the (self-driving system) meets a standard developed and designed to apply to a vehicle with a human driver,” according to the NHTSA.
NHTSA says a badly-designed automatic shifter is confusing drivers, causing them to exit a vehicle that’s still in gear. 121 crashes and 30 injuries have been reported.
This past summer the National Highway Traffic Safety administration opened a preliminary investigation into just over 400,000 Jeep Grand Cherokees after some owners alleged their vehicles would roll away after being shifted into Park. Now, the NHTSA has more than doubled the number of Jeep, Dodge and Chrysler vehicles being investigated and the agency now blames the problems on a confusing shifter design that doesn’t adequately indicate to drivers that they haven’t engaged Park.
The Detroit News reports that the NHTSA is conducting an engineering analysis on more than 856,000 Fiat Chrysler vehicles. The agency has received reports of 314 roll-away incidents, involving 121 crashes and 30 injuries, caused when drivers exited a vehicle after they thought they’d shifted into Park. And while the initial investigation treated the issue as a mechanical defect, it’s looking more and more like the problem has at least something to do with driver error due to a poorly-designed shifter.
The investigation involves 3.6-liter V6-powered 2014 and 2015 Jeep Grand Cherokees, 2012-2014 Dodge Chargers and 2012-2014 Chrysler 300s—all of which use a push-button console shift lever that looks like a traditional PRNDL shifter. But in operation, the electronic shifter works more like a joystick, returning to its center position once you’ve selected your gear. There is no gate around the shifter; the lever itself moves through somewhat subtle detents, and the whole range of motion is incredibly short compared to a traditional mechanical shifter, perhaps two or three inches from end to end.
The console shifter on a 2014 Jeep Grand Cherokee. The Dodge Charger and Chrysler 300 models included in the investigation use an identical shifter.
It’s worth pointing out that the aforementioned Fiat Chrysler vehicles are not the only ones that use this shifter, which is called the Monostable and is produced by transmission supplier ZF. As an example, Audi A8 uses an identical shift knob, with the thumb button on the left and a PRNDS gear pattern with no separate button for Park.
In testing, NHTSA found that the electronic gear shifter’s operation is “not intuitive” and offers “poor tactile and visual feedback to the driver, increasing the potential for unintended gear selection.” In Fiat Chrysler vehicles equipped with this shifter design, opening the driver’s door when the car is not in Park triggers a chime and an instrument cluster alert, and the engine cannot be turned off with the car in gear; however, NHTSA says “this function does not protect drivers who intentionally leave the engine running or drivers who do not recognize that the engine continues to run after an attempted shut-off.”
So while it may seem silly that drivers could be confused by the operation of an automatic transmission, the reality is that this shifter design operates differently enough to require more concentration than a traditional shifter. Folks who’ve been driving for years, who are used to the way a mechanical PRNDL shifter operates, probably don’t think consciously about the act of shifting—it’s the kind of act we’ve committed to muscle memory years ago.
NHTSA has upgraded its treatment of this problem in FCA vehicles from an investigation to an “engineering analysis,” though no plans for a recall have been announced at this time. FCA went to a different shifter design in model-year 2015 for the Dodge Charger and Chrysler 300, and changed the Jeep Grand Cherokee shifter for 2016.
via Detroit News
Friday, February 5, 2016
Contact: Gordon Trowbridge, 202-366-9550, Public.Affairs@dot.gov
The U.S. Department of Transportation’s National Highway Traffic Safety Administration today announced its latest estimate of traffic deaths, which show a steep 9.3 percent increase for the first nine months of 2015. The news comes as the agency kicks-off its first in a series of regional summits with a day-long event in Sacramento, Calif., to examine unsafe behaviors and human choices that contribute to increasing traffic deaths on a national scale. Human factors contribute to 94 percent of crashes according to decades of NHTSA research.
“For decades, U.S. DOT has been driving safety improvements on our roads, and those efforts have resulted in a steady decline in highway deaths,” said U.S. Transportation Secretary Anthony Foxx. “But the apparent increase in 2015 is a signal that we need to do more. The safety summits that NHTSA is kicking off today in Sacramento will provide us with new approaches to add to the tried-and-true tactics that we know save lives.”
NHTSA estimates that more than 26,000 people died in traffic crashes in the first nine months of 2015, compared to the 23,796 fatalities in the first nine months of 2014. U.S. regions nationwide showed increases ranging from 2 to 20 percent.
“We’re seeing red flags across the U.S. and we’re not waiting for the situation to develop further,” said Dr. Mark Rosekind, NHTSA Administrator. “It’s time to drive behavioral changes in traffic safety and that means taking on new initiatives and addressing persistent issues like drunk driving and failure to wear seat belts.”
The estimated increase in highway deaths follows years of steady, gradual declines. Traffic deaths declined 1.2 percent in 2014 and more than 22 percent from 2000 to 2014.
Today’s summit in California is the first in a series of cross-cutting regional summits being held across the country, capped by a nationwide gathering in Washington, to gather ideas, engage new partners, and generate additional approaches to combat human behavioral issues that contribute to road deaths. These summits will address drunk, drugged, distracted and drowsy driving; speeding; failure to use safety features such as seat belts and child seats; and new initiatives to protect vulnerable road users such as pedestrians and cyclists.
A new study conducted by the Insurance Institute for Highway Safety (IIHS) has found that vehicles equipped with front crash prevention systems are far less likely to be involved in a rear-end accident than those vehicles without such systems.
Though not a shocking conclusion, the results show that there is a real benefit to front crash prevention systems. According to the study, automatic braking systems reduce rear-end collisions by about 40 percent on average. Forward collision warning systems, which warn drivers of an impending impact but don’t apply the brakes, were found to reduce rear-end crashes by 23 percent. The IIHS estimates that if all vehicles were equipped with automatic braking systems there would have been 700,000 fewer rear-end collisions in 2013.
“The success of front crash prevention represents a big step toward safer roads,” says David Zuby, IIHS chief research officer. “As this technology becomes more widespread, we can expect to see noticeably fewer rear-end crashes.”
Moreover, the study found that rear-end crashes involving vehicles equipped with auto braking had a 42 percent decrease in reported injuries. That figure jumps to 47 percent with Volvo’s City Safety system.
“Even when a crash isn’t avoided, systems that have auto brake have a good chance of preventing injuries by reducing the impact speed,” says Jessica Cicchino, the study’s author and the Institute’s vice president for research.
Forward collision warning systems alone, however, didn’t have a measurable effect on injuries. The study found that such warning systems reduced injuries by only 6 percent, which isn’t statically significant. “It’s surprising that forward collision warning didn’t show more of an injury benefit, given that HLDI (Highway Loss Data Institute) has found big reductions in injury claims with the feature,” said Cicchino.
Although auto brake systems are clearly beneficial, IIHS notes that such systems are often bundled with other technologies like adaptive cruise control, so their exact effectiveness is difficult to track.
The IIHS along with the National Highway Traffic Safety Administration announced last year that they has reached an accord with automakers to make auto braking standard across all vehicles, but a date for that implementation has not been set.
Read more: http://www.leftlanenews.com/front-crash-prevention-systems-reduce-crashes-injuries-iihs-study-90863.html#ixzz3yf5zFj27
The Insurance Institute for Highway Safety (IIHS) is a non-profit organization that performs testing and research on new cars in order to assign safety ratings. The IIHS conducts various crash tests on new vehicles and assigns ratings based on how they do. They have five main tests to determine crashworthiness: Moderate overlap front, small overlap front, side, roof strength and head restraint. They then rate the vehicles as “good,” “acceptable,” “marginal,” or “poor” in each test.
While there are undoubtedly numerous factors in addition to vehicle design which effect a vehicle’s crash worthiness, the IIHS tests have proven to be fruitful. Their ratings help consumers make better informed decisions and have pushed automakers to produce safer vehicles. A comparison of death and injury reductions for vehicles with a “good” versus a “poor” rating in IIHS tests shows the following:
- Front offset with moderate overlap test: Fatality risk in head-on crashes is 46% lower
- Side Impact Crash Test: Fatality risk in side impact crashes 70% lower
- Rear Impact Test (seat only): Neck injury risk in rear crashes is 15% lower and the risk of neck injury requiring 3+ months treatment is 35% lower