Googling truck and bus accident images will throw up horrific scenes. Mangled remains of trucks by the roadside; burnt buses displaying their raw structure; head-on collisions between a truck and a bus, or between a pickup and a car appear in quick succession. If they bring to mind the three laws of Sir Isaac Newton, and how they seemed to have found application, it is at once clear that safety is not to be taken lightly. May it be on the move or even when stationary. Not in an active sense or in a passive sense either. It is therefore not surprising to find OEMs and suppliers testing new safety systems on test tracks almost tirelessly. At the same time, engineers and designers in front of large computer screens toil to develop new safety apparatus, and better what has already been developed. As the quest for autonomous driving vehicles and zero accidents gains force, active and passive safety systems get a shot in the arm. And, irrespective of whether a collision mitigation system will work on an Indian truck or a bus. In India, the latest developments in the area of safety include a government order to fit a certain class of trucks and buses with ABS. The developments also include a mandate for Bus Code, which speaks about the use of approved materials and
coach work.
Active safety
Defined as a system that is activated in response to a safety problem or an abnormal event, active safety in an automobile could mean a function as simple as good steering and good brakes. Starting with a good steering and good brakes, active safety has gone much beyond however. It has come to include mechatronic developments like brake assist, traction control, electronic stability, etc. Employing sensors that interpret signals to help the driver control the vehicle, active safety systems have also come to include advanced driver assistance systems like adaptive cruise control and collision mitigation systems. In the development of such systems are involved tier 1 suppliers like Wabco, Knorr Bremse, Bosch, Continental and many others. They continue to work closely with OEMs to turn out systems that make an automobile safe. At the risk of reducing the driver to a mere passenger almost.
What works in USA or Japan may not work in India however. It does not come as a surprise therefore when Jacques Esculier, Chairman and CEO, Wabco Holdings Inc. opines that it is not desirable to introduce collision mitigation system in India because one is always prone to a collision due to the heavy traffic. “You may need a different kind of functionality depending upon the speed itself. This is the work that we are doing right now to provide the best optimised system that will benefit the Indian market,” he adds. Wabco commands a large chunk of the commercial vehicle market in India for brakes. The company, based at Chennai, also supplies ABS to most commercial vehicle manufacturers in the country. Apart from collision mitigation system, some of the active safety systems that Wabco has been working on, include AMT, which Esculier claims, helps the driver concentrate on the road better. Describing ABS as a major cornerstone to enhance safety, Esculier drew attention to the need to manage energy without challenging the safety of the vehicle. Especially in the case of hybrid vehicles that are emerging. India will also get them, albeit later than that of Europe
or USA.
If the Freighliner autonomous truck has demonstrated that it can drive itself without the help of a driver under varying conditions, the success marks the rise of active safety systems to the next level. Passive safety systems can’t be ignored either. In case a collision is unavoidable, they reduce
the damage.
Passive safety
Aimed at reducing damage, passive safety systems include seat belts, airbags, safety seat structures, head restraints, crumple zones and energy absorbing body structures. Passive safety systems protect vehicle occupants from injury in case of a collision. They are engineered such that they create a safe zone for vehicle occupants in case of an impact. Ensuring that the vehicle occupants remain in the safe zone throughout the crash, they work such that a seat belt, airbag and headrest will keep the driver and passenger safe by limiting him to the safety zone. Reduce the risk of serious injury.
Also a part of passive safety are measures like the positioning of fuel tank in a truck or a bus. Engineering a collapsible steering column. The engineering of crumple zones, and the design of the cab. A part of the cab design are issues like the view outside. In other words, providing the driver of a truck or bus with unobstructed, long-range visibility of both the road and approaching obstacles. This could be done with the help of full close- and long-range rear view mirrors; large, well-positioned and adjustable mirrors, and advanced alternatives like, camera systems with full-frontal display monitors. When driving at night, automatically levelling headlights help to enhance safety. Also, directions indicators, position lights and side indicators improve safety. Not just for the driver of a truck or bus, but for other road users. Even technologies like auto transmission and Automated Manual Transmission (AMT). The driver of a CV is able to focus more on driving rather than split his focus between the road and the controls. In case of automatic transmissions, supplementary safety features like door integration (gears cannot be engaged when the door is open; door will not open when the vehicle is in motion) and no roll back when in drive-mode also help to enhance safety.
New developments
New developments continue to emerge in the area of commercial vehicle safety. Airbags do not just inflate out of the steering column but also appear along the side-panels and even around the knees. Advanced seat belts moderate the amount of tension across a person’s body, and reduce instances of seat belt-related injuries. A major safety application that enhances safety, but is yet to reach out to Indian CVs include tyre pressure monitoring systems, camera monitor systems, adjustable steering and steering mounted controls to operate the vehicle features to avoid distraction of drivers. Tyre pressure monitoring systems, monitor tyre pressure and alert the driver via a display and an audible alarm in case the pressure in the tyres depletes beyond a certain limit. Capable of monitoring tyre temperature, the systems warn the driver when there is a fire hazard or a tyre burst risk.
Camera monitor systems are said to provide the same level of functionality that traditional mirrors provide. Interest is therefore growing in Europe and USA towards this technology. Indian CV manufacturers are prioritising driver safety and overall drive enhancement of CVs. They are likely to embrace these new technologies that promise greater safety, just as we saw the acceptance of ABS and Bus code.
Indian safety requirementsCommercial vehicle safety in India is mainly governed by regulatory requirement – AIS 029. As a part, the cabin of a truck is subjected to frontal impact test, roof strength test and rear wall strength test. Other than these tests the truck is also tested by loading it to the maximum. Test are also conducted to avoid small vehicles and pedestrians coming under the wheels of the trucks. Under run safety provisions are made. This includes UPDs (Under run Protection Device) like, SUPD (Side), RUPD (Rear) and FUPD (Front). This devices are added to the trucks in India under AIS(069), IS:14812 and IS:14682. Lighting, primarily at the rear-end, forms one of the core requirements of the passive safety. However, rear lighting systems alone are not enough to make a truck visible. It is also mandatory to have conspicuity marking under the regulation AIS 090. International studies revealed that the presence of reflective tapes can result in 41 per cent fewer rear end collisions and 37 per cent fewer side collisions. Mandatory conspicuity markings under AIS 090 comprise of colour and width of marking. For side to be marked in yellow, the width is 50 mm. Rear should have red reflective tapes of 50 mm width. For vehicles exceeding 2.1 metres width at the rear, a red full contour marking is mandatory. Similarly vehicles exceeding 6000 mm in length should have partial yellow contour marking. Roll Over Protection (ROP), mostly for buses, comes under (AIS 031). Bus rollover is one of the most serious types of accidents. ROP ensures adequate strengthening of the bus frame to maintain life space (occupant space) and minimises occupant injuries.
The Scania Metrolink bus, for example, is equipped with a Fleet Management System (FMS), fire detection and suppression system, six emergency exits with twelve hammers, emergency doors and flight like safety video to educate passengers on do’s and don’ts, at the time of emergency. All the Scania products also comply with R66 standard which is formulated to ensure, best possible safety even in case of vehicle roll over and accident, tested and certified by TUV, Germany. To reduce the wear and tear of the braking system, Blended Retarder (BR) in the Scania products improves safety by keeping the service brakes cold for full emergency performance, and also adds on to the stability of the vehicle while braking. The engine and bus body is built with 100 per cent fire retardant material. Other advantages such as shorter turning radius for easy manoeuvring and Scania Opticruise, a fully automated manual gearbox, helps the driver concentrate better.
Volvo too has introduced several new concepts and technologies like the Volvo Electronically Controlled Suspension (ECS), Electronically Controlled Brakes (EBS), Volvo Engine Management System (EMS), ABS, kneeling mechanisms in city buses, FUP/FIP safety systems in all coaches, and bus multiplexing. With the introduction of each of these technologies, Volvo raised the benchmark in terms of safety, performance and reliability. Monocoque coach construction specialist Corona who has delivered the company’s Majestic AC sleeper coach to the North West Karnataka Road Transport Corporation (NWKRTC) and the North East Karnataka Road Transport Corporation (NEKRTC)claims that the space frame structure, increases passenger safety.
