Highway 401 – Median Barriers, Construction & Other Complaints Are Studied
What decisions do drivers make when their lane is ending and they are traveling at highway speed? Gorski Consulting has conducted testing with traffic cameras on Highway 401 to find out.
At highway speeds, with high traffic densities and a sudden emergency, drivers need to make quick decisions that could cost them, or drivers around them, their lives. Decades of research has helped to create the roadway environments that reduce the need to make those sudden decisions. Yet, unexpected events can occur.
Highway 401 in southern Ontario has received its share of complaints. From Windsor to Montreal this super-highway carries the highest numbers of Canadian drivers, by far, than any other. Its character changes greatly whether it contains multiple express and collector lanes in Toronto, or whether it contains only two lanes without a median in areas east of Kingston or close to Chatham.
Construction, maintenance and policing activities become a problem when traffic volumes increase. Often lanes become closed for these activities and drivers must make adjustments in their speed and lane travel. Numerous collisions occur in construction zones when closed lanes cause drivers to change lanes or bring traffic to a halt. Many collisions occur when unsuspecting drivers approach the stopped traffic at highway speed but are too late in their detection that traffic is stopped. This is more problematic when heavy trucks are loaded with cargo but their braking systems make if difficult to stop as quickly as passenger cars and light trucks. Numerous problems like these require objective data in order to develop counter-measures that provide realistic solutions to the problem.
Recently Gorski Consulting has been conducting observations along Highway 401 to gather the objective data that may form the grounds for improvements in the future. The use of synchronized, multiple, video cameras, placed in a short-range environment, allow for data to be collected about driving patterns and drivers’ actions.
The most recent observations were conducted on October 30, 2018 on Highway 401 near the Westminster Driver overpass on the outskirts of London, Ontario. This location has moderate traffic volumes that allow a relatively free flow. Considerable construction activities are currently taking place between Chatham and London however, at the time of the observations, no such construction activity existed in the vicinity.
The typical procedure is to paint markers at 100 metre intervals along the road edge. A video camera is pointed at the marker and it documents when vehicles pass that reference point. At the next 100 metre location another video camera captures the same vehicle. By knowing the time interval that it takes a vehicle to pass between the two markers an average speed is obtained. Other information such as the following distance of one vehicle behind another is also obtained.
Video cameras placed along the side of the highway document vehicles as they pass by paint markers and traffic cones placed at 100 metre intervals. This method provides information about the average speed of the vehicles.
The Westminster Drive site is particularly useful because the westbound lanes of Highway 401 become reduced from 3 lanes to just 2. This produces observations of drivers who must change lanes. Information about how long drivers wait to change lanes before reaching the end of the lane can be useful as failures in this decision making can be the source of collisions. Information is also obtained about how other drivers react to a vehicle attempting to cross into their lane and if they are accommodating and helpful or otherwise.
Panoramic views along the highway are also taken from the Westminster Drive overpass with cameras pointing east and west. This provides an additional perspective of the traffic.
View of two video cameras positioned on top of the Westminster Drive overpass and pointing at traffic east and west of the location.
Decisions regarding when to make a lane change are still far away from being completed by self-driving vehicles. While an algorithm developed through substantial research may provide the correct response in high percentages of instances, there are still situations where a human driver may be able to foresee something that the computer cannot, thus requiring human control to change the vehicle’s motion.
In this view the driver of the red car has succeeded crossing out of the ending lane at the very last instance. Decisions such as these can be problematic when traffic volumes are high and opportunities to make that lane change are limited.
The study of human decisions and how they drive can be beneficial to the creators of self-driving vehicles because, even if self-driving cars fully populate the road system there will still be a long ramp up process when self-driving cars will need to live among human decision makers.
Farm Tractor Lighting – Not Enough, Too Much or Too Confusing
Farm tractor lighting can lead to collisions when drivers do not understand their difference from typical motor vehicles.
When approaching a farm tractor from the rear drivers often assume that the lighting and its meaning is predictable much like city traffic. There are differences that could prove deadly. The lighting on the tractor in this photo is partially obscured making it appear that the vehicle will be making a right turn.
Farm tractors, much like construction equipment, often contain extra, flashing, lights that are located at portions of the vehicle that are not common. Drivers from urban areas who are not familiar with approaching such vehicles can obtain the wrong information about what the lights mean. Many farm vehicles are equipped with flashing amber lights that appear to be the same as the turn signal lights of urban vehicles. When a full view of the lighting is not observed a driver may believe the farm vehicle will be travelling straight ahead or making a right turn and attempt to pass. At the last moment the opposite may be true.
Because the left turn signal is obscured an approaching driver might begin to pass the tractor without knowing that the tractor is preparing to make a left turn.
This is something to think about next time you approach farm vehicles.
OPP Speed Enforcement on Hwy 401 – Actual Observations Indicate Greater Problem
View of Highway 401 near Elgin Road (Highway 73) in Middlesex County where an observational study was conducted to estimate the average speed of vehicles travelling in the median (fast) lane.
The OPP reportedly conducted a two-day “aerial blitz” of speeding vehicles along Highway 401 last week. The number of charges are far below the actual number of speeders that could have been ticketed. It was reported that 72 charges were laid, 38 of which were for speeding. Observations of the speed of drivers conducted by Gorski Consulting indicate that this must have been a very short or very selective enforcement because of the actual number of speeding drivers that actually exist.
In the Gorski Consulting study conducted in November of 2016, near the interchange of Highway 73 east of London, Ontario, westbound traffic was documented with multiple video cameras for slightly less that 8 minutes. In that time 62 vehicles were observed travelling along the fast lane, or the lane closest to the median. Twenty-four, or 39%, of those vehicles were observed to be travelling over 120 km/h. Matching this data to the 38 speeding charges by the OPP, and assuming the location of their blitz was at a similar traffic volume, it would suggest that the OPP observed less than 15 minutes worth of traffic during the blitz. The OPP were quoted as saying this blitz was “designed to increase public compliance with safe driving measures”. This may help to publicize the extent of the problem but the blitz itself is unlikely to have had any effect on the speeding habits of drivers.
The difference in the numbers of observed speeders and what charges were laid outlines an obvious problem about the lack of enforcement of speed limits along Highway 401. The reality is that pulling vehicles over for a speeding violation along the Highway is a dangerous operation that could produce more harm because of the potential collisions that it can cause. While a “move over” law requires drivers to slow down and change lanes away from emergency vehicles the reality is that such changes in speed and direction are themselves the cause of collisions. In many instances speeding drivers cannot change lanes quickly enough because of factors such as visibility problems and traffic density. The sudden reduction in speed of vehicles causes speeding drivers to brake suddenly and cause problems for other speeding drivers around them. While it can be said that this is the fault of those speeders it never-the-less does not prevent the causation of serious consequences.
The other reality is that there is likely not enough police available to deal with the speeding problem. Enforcement could reduce the speed of vehicles over an extended time when drivers begin to recognize that police are monitoring drivers’ speeds on a regular basis. But this takes manpower that our society is presently unwilling to pay for.
Under these difficult realities technological advances such as the implementation of automatic emergency braking cannot come fast enough, particularly for heavy trucks and buses. While this may not be a panacea in itself, early findings indicate it could make a large difference in the types and severity of collisions that occur on high-speed freeways like Highway 401.
Extreme Case of Bumper Over-Ride Highlights A Common Safety Issue
Sometimes eye-catching photos of extreme bumper over-ride can draw the public’s attention to more meaningful consequences.
An extreme case of bumper over-ride was published on the OPP’s West Region twitter account today. The front end of a tall pick-up truck was shown on top of the hood and windshield of a small passenger car and the incident reportedly occurred in the area of Norfolk County, Ontario. OPP reported no one was injured from the incident and that is good news. More importantly these views may have caught the attention of many persons who would ordinarily be too busy with seemingly more important matters in their lives – until they are caught up in a major collision that threatens them.
While the view of one vehicle on top of another appears dramatic, a closer analysis reveals a relatively, low severity event. But it raises awareness to other issues.
Views from this present incident indicate that it was more eye-catching than life-threatening. There is minimal crush visible on both vehicles. Even the interior of the car shows minimal potential for intrusion into the driver’s space and the air bag did not deploy. That is the goods news. But this scenario outlines much more serious concerns.
Even though the left front wheel of the pick-up truck is partly onto the car’s windshield there was minimal structural intrusion into the driver’s space and the air bag did not deploy.
Even a quick glance at my reference library shows a copy of a Society of Automotive Engineers (SAE) manual from 2005 entitled “Vehicle Aggressivity and Compatibility in Automotive Crashes”. This is a compendium of research papers related to collisions similar to what is shown in the above photographs. Even early in my career, in the 1980s while I was conducting investigations of over 100 major collisions a year, I had developed a theory from studying the results of hundreds of head-on collisions including a specific study of Light Truck and Van (LTV) collisions that was conducted over a period of over 3 years. The theory I developed was that, if one wanted to survive a major head-on impact at relatively low cost, one should buy a four-wheel-drive, Chevrolet Suburban. The Suburban was stiff, it had a wide stance and its bumper was taller than most passenger cars. My studies demonstrated that, in a head-on impact, the vehicle that rode over top of the other vehicle’s front end resulted in a better chance of survival for the over-riding driver. That observation was true in many ways for many years.
Not long after the owners of pick-up trucks began placing lifters on their suspensions and the bodies of their trucks began to rise higher. Even manufacturers began building light trucks with higher suspensions. It can be seen of the Chevrolet Silverado in the above example that its body is well above the typical height of an old-style truck of the 1980s. The advantage of a higher body was often seen in Jeeps which also had a stiff bumper/frame that was higher than typical passenger cars. The drawback of Jeeps however was that they had a smaller wheelbase and track width than a Suburban and were more prone to instability, particularly after the initial head-on impact. And this leads to another issue regarding survivability, height and instability that few would expect.
As I originally observed “height wins”, But not in all facets. Height wins during the initial 110 milli-seconds as two vehicles reach they point of maximum engagement (maximum crush) and the stiff bumper area of the taller vehicle drives through the softer upper regions (hood, fenders, etc) of the vehicle beneath. But often the vehicle collision does not end there. In most instances a head-on collision involves 60 percent or less of a vehicle’s front end. This means the vehicles’ centre-of-gravity do not line up and that the collision is not “central” but is off-set. This means that, although much of a vehicle’s velocity could be lost in the initial impact, the vehicle may also have additional, residual velocity after the initial impact. This is more true of taller vehicles because they are also likely to be more massive and they are less likely to be stopped by the lower, less-massive, collision partner. The bottom line is that this taller vehicle which rides over the top of the lower vehicle now becomes destabilized. That destabilization often involves the lifting of only the struck half of the vehicle such that, upon leaving the area of impact this taller vehicle has a greater tendency to begin to rollover rather than slide on its wheels to final rest.
So, having survived the initial impact because of the vehicle’s superior body height and mass, this driver is now faced with a possible substantial, post-impact velocity while commencing a rollover. This may not sound threatening because we know that, as long as the driver is properly restrained in a seat-belt, and stays within the safe confines of his/her vehicle, the deceleration rate of about 0.5 g will be of minimal consequence. But that is not the only issue.
In a major head-on impact there is a higher probability that the direct contact damage and crush is to the left front and thus a varying amount of deformation can occur which can exist as far back as the driver’s door without producing any serious structural intrusion. Meanwhile, near the end of this same impact, after the air bag starts to deflate and the driver is out of position, the relationship between the restraint system may not be ideal and the various components such as the door, side window or window sill may not be of the same shape as it was pre-crash. There is no guarantee therefore that a driver will stay comfortably confined by the restrain system, in a properly seated position, while the vehicle goes through a post-impact rollover with a substantial post-impact velocity. Partial ejection of the upper torso and head during these occasions have resulted in deadly consequences.
Too often the public has seen TV commercials demonstrating how a vehicle occupant is ejected clearly out of their vehicle and sustained their fatal injuries from striking the exterior environment. While this is one mechanism by which fatal injuries occur it is by no means the only mechanism. Whether it is full ejection or just partial ejection the body of the ejected occupant is in the vicinity of the vehicle when that vehicle is rolling over. The result is that the rolling vehicle may actually crush the ejected occupant’s body several times during the rollover before both come to their rest positions. Thus the lucky driver whose taller and heavier vehicle allows he/her to survive an initial impact may sustain fatal injuries from the seemingly less dangerous post-impact motion to rest.
Another important issue that is illustrated by the above photographs is air bag deployment. Note that the air bag in the small passenger car in the above photos did not deploy. Certainly this could be for a reasonable and foreseen eventuality programmed in the algorithm of the air bag control module. But one really knows. The triggering of air bags and the algorithms of how that is done is considered proprietary information that is only available to the manufacturer. I belong to several internet chat group of over 1000 international reconstructionists and there are many occasions where such investigators pose the question: ” Should the air bag have deployed in this described case?” or conversely “Should the air bag have not deployed considering the the low severity of this described case?” While a number of experts are willing to propose various reasoning for why the deployment should nor should not occur, the reality is that, without the details of the decision-making continued in the control module, it is only conjecture.
When vehicles of very different heights come into a head-on collision it becomes problematic, not only for the manufacturers to detect when an certain scenario requires air bag deployment, but investigators outside of the manufacturers also have a greater difficulty in making a correct determination of what should have happened. The reality is that the decision to deploy an air bag has to be made in a very short of time of 25 to 50 milli-seconds and that is well before there is enough information to know how the complete collision will eventually unfold. Much of the decision-making is made about the rate at which the velocity is changing. In fact the decision is made partly on the rate at which the acceleration is changing, which is referred to as Jerk. But no one can be sure what additional factors are taken into account or how. So the above photos help to bring attention to this fact that vehicles of different heights cause problems when they collide because the sensors that are positioned to capture the typical collision may not sense a collision in sufficient time to make a proper decision about air bag deployment.
In the end it does not create much harm when the OPP place photos on their Twitter account of a seemingly harmless and meaningless collision that catches the public’s attention. It gives me the opportunity to catch the public’s attention and discuss some consequences that could be major factors in their lives or of those near to them.
School Buses and Seat-Belts – The Issue Is Not So Clear-Cut
The Canadian Broadcasting Corporation (CBC) has recently broadcast a documentary (The Fifth Estate) and published articles discussing its investigation into an alleged improper decision by Transport Canada to prevent school buses from being equipped with seat-belts. An article published on the CBC website on October 14, 2018 claimed that “thousands of injuries” and “numerous deaths” would have been prevented if school buses were “on school buses”.
While I respect the CBC’s many admirable documentaries that enlighten Canadians about important issues, this latest discussion has missed the mark and may be more misleading than it is helpful.
As an example, the CBC website article showed photographs submitted by Kirsten Hodgeson of a 2008 school bus collision near Rimbey, Alberta where the bus was rear-ended by a gravel truck resulting in the death of a 17-year-old passenger. Two photos of that rear-ended bus are shown below.
In this 2008 rear end impact it was claimed that the deceased passenger of the school bus would have been saved if she was not ejected from the bus and it was the ejection that was the cause of her death.
Keenen Clark, a student who survived this crash, claimed that it was his ejection from the bus that caused his major injuries.
Keenen Clark, a student who survived the crash was quoted as saying “if seatbelts would have been on the bus, Jenny (Noble) probably would have stayed on the bus. Everything that happened to me happened after I fell out of the bus”. Referring to the crash the CBC seemed to agree, noting “..the need for seatbelts seems obvious”.
The need for seat-belts is a separate issue, but the discussion of this rear-ended school bus incident is misleading and harmful to the understanding of the important issues. The school bus was reportedly stopped in fog when it was struck by a gravel struck which glanced off the right side of the bus and came to a stop a short distance ahead. The impact was of a narrow offset such that one can see that the main structural components of the bus, such as its frame, were not deformed and were not involved in the dissipation of the truck’s kinetic energy. In short, the collision was not one where the bus sustained a large change-in-velocity. Change-in-velocity is what is used to determine the severity of an impact and its potential to cause injury. The primary issue in this crash was that the relatively soft structure of the bus was crushed resulting in substantial intrusion into the passenger compartment. This intrusion can be seen in the above photo where the seats of the bus have been deformed and displaced. The fact that some passengers were ejected from the bus was not the primary issue as their ejection from the stopped bus should have been at low speed and of minimal injury potential. For this collision the important factor that would lead to injury/death is the structural intrusion and not the change-in-velocity or the ejection. Seat-belts are often of minimal effectiveness when there is substantial structural intrusion into where the occupant is seated, as was likely the case in this school bus crash. While Keenen Clark may have an opinion he is not an expert in injury caution and his understanding of what caused his injuries is in error.
Never-the-less the issue of whether seat-belt use by children on school buses is an important one and not easily or clearly resolved.The authors of the CBC study suggested that Transport Canada deliberated hid the the fact that seat-belts on school buses could have prevented many injuries and deaths. That statement is true but it is also false. It is false because it fails to underline the important cautions in the Transport Canada study: that seat-belts can also be the cause of injuries and fatalities to children. The CBC authors failed to understand and properly inform the public just how precarious it is to restrain children of various sizes and ages into standard seat-belts than may not properly accommodate their anatomy. Even if there was a properly trained adult on board a bus who could initially place a seat-belt into a proper position on a child, anyone ought to know that children will not stay seated in an ideal posture for any extended time. Yet this is what is needed to ensure that the restraint system will function as it should. The CBC authors failed to understand why it is that booster cushions are required for certain ages of children – precisely because adult restraint systems do not fit a child properly. The authors fail to understand the large danger when the lap portion of a restrain system is not sufficiently tight and is not positioned below the child’s illiac crests (the frontal bony structure of the pelvis below the soft abdomen). Those who are familiar with injury assessment and seat-belt effectiveness know the tragic results when a child suffers fatal abdominal injuries in relatively moderate crashes because the lap belt was not in a proper position and the child “submarined” under the lap belt. The installation of 3-point restraints will not guarantee that such submarining will be prevented as the primary issue is the initial position of the lap with respect to the pelvis and the ultimate geometry of the restraint system.
I am not surprised that Transport Canada officials remained tight-lipped about discussing their findings or that they appeared to be hiding their research results. I am certain that they are aware of the dangers that could be introduced if un-monitored seat-belt use became prevalent on school buses. It would only require one incident where a school bus sustained an impact involving a major change-in-velocity and the bus was fully-loaded with a wide array of children of different sizes “wearing” their seat-belts. We would see the tragedies that would unfold. Numerous children would suffer abdominal injuries, some of these fatal, and there would be an outcry about the dangers of seat-belt use. If you could pick which collision a bus would be involved in then it would be simple to select the safety measures that could protect the occupants. But reality is not like that. Knowing the dangers of mis-used seat-belts researchers attempted to minimize the problem by introducing the idea of compartmentalization, that is, keeping children within the confines of where they are seated and using designs to minimize the injuries resulting from children being “bounced around” during an impact.
What the CBC authors failed to understand is that there has been substantial research into identifying the typical collision in which a school bus is likely to be involved. While not fool-proof such research has identified that in most cases a large school bus is more likely to be involved in an impact with a smaller vehicle such as a passenger car or light truck. Therefore the expected change-in-velocity of the bus is likely to be low because of the large mass difference between the striking vehicles. Seat-belts are helpful in reducing the forces in such larger changes-in-velocity but they are of less need for lower severity impacts such as rollovers. Rollovers can be dangerous if occupants are ejected however they can be of moderate injury potential if occupants are confined within the cage of the vehicle interior because in a rollover the change-in-velocity is very gradual and far less severe. Yes, children can be injured while tumbling inside a bus that is rolling over but this is a matter of severity of injury. It is the difference between sustaining lacerations, contusions and less severe concussions from tumbling versus sustaining potentially massive tears of major adominal organs from a mis-positioned seat-belt. When multiple children sustain those major injuries it would be virtually impossible to transport them in time to surgery and deal with those injuries when there are immediate requirements of multiple patients and only a limited number of surgeons. These are the types of complex issues that are involved.
I have no doubt that researchers have explained the issue to administrators at Transport Canada and these persons recognize that they car caught “between a rock and a hard place” such that there are no easy alternatives. The issue of abdominal injuries caused by seat-belts has been a difficult one even for adult occupants. When there is no easy solution yet you are the administrator or researcher who must make a difficult decision it is often believed to be best if the problem is not discussed. Thus the reason for Transport Canada’s apparent silence. Full disclosure of the real problems is complicated when the explanation requires a substantial technical understanding of the details that cannot efficiently passed onto a public that has a short attention span and is more interested in an explanation that is simple and fits their biases .Thus when these issues are often misrepresented to the public there is no guarantee that the correct message will be delivered as it should be.
While I am not in a position to know for certain, a compromise might be reached with improving the compartmentalization of children by equipping school buses with air bag curtains much like those in passenger cars. This might improve the chances that children might remain contained inside the school bus interior when it is involved in a side impact or as it rolls in a typical, lateral fashion. I am certain that researchers more familiar with the issue have already thought about this possibility. The potential costs of fitting a large school bus with sufficient lengths of side curtain and the subsequent costs of re-fitting a school bus after the bags go off would appear to be major drawbacks to this idea.
Regardless, this discussion outlines the extreme importance of conducting thorough documentations of school bus collisions by unbiased experts who can also properly and fully pass the results of those investigations openly to whoever needs to know. This is a continual problem that prevents many safety issues from being resolved promptly and efficiently.
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