Windscreens: The future of glass replacement
30 October 2015
The advent of new in-car safety equipment means that fixing cracked windscreens is no longer simply a case of swapping panes of glass, as Christofer Lloyd reports from a recent Autoglass conference
Windscreen repairs are something of a necessary evil for fleet managers, but the process could become much more complicated in future as modern in-car safety technology will need to be recalibrated following a windscreen replacement - adding extra time and cost.
Speaking at Autoglass's 'Window to the Future' conference on 8 October, Chris Davies, head of technical superiority at Belron - Autoglass's parent company - highlighted how the move to autonomous cars and use of advanced driver-assistance systems (ADAS) is making windscreen replacement an increasingly complex job.
While the process traditionally involves nothing more than swapping the damaged pane for a new one, modern in-car safety kit - which often relies on cameras mounted behind the windscreen - can necessitate a recalibration process to make sure that the car's safety kit continues to work properly.
This could be a static process with the car parked in front of a recalibration screen or require the vehicle to be driven for around 15 to 30 minutes on the road - depending on the manufacturers' stipulations - with Audi, Mercedes and Renault models needing a static calibration and others including BMW, Ford and Volvo models requiring 'dynamic calibration'.
Reinforcing the importance of adjusting safety kit after fitting new glass, Neil Morgan, legal director for Belron, stated that even slight movement of a windscreen-mounted camera could result in a dramatic shift in what it sees.
This potentially affects how effectively safety kit such as automatic braking systems can operate - something that is particularly important as drivers are unable to view a camera's output and determine whether it is properly adjusted for themselves, meaning that "failure to calibrate could result in a safety risk", according to Morgan.
Showing the extent to which this is a growing issue, Davies pointed out that while just 1% of the company's windscreen replacements involved ADAS-equipped cars in 2014, this figure is predicted to rocket to 40% by 2020, partly thanks to European crash test body EuroNCAP encouraging the use of camera-reliant safety systems.
With the addition of calibration to the windscreen replacement process, installing new glass will become a more lengthy affair, requiring technicians to wait an hour after fitting for the new windscreen adhesives to seal before taking to the road for a 'dynamic calibration'.
"Once that's happened we can plug in the diagnostic tool and then we have to drive for a certain amount of time," stated Davies. "Usually we say that's a minimum of 15 minutes but it depends on the time of year, the traffic conditions, what road you're on, because the camera system basically needs to look for enough street furniture - lampposts, bollards, white lines."
Meanwhile, vehicles that allow static calibration will have to be taken to an Autoglass site to be calibrated in the short term, with the company planning to make this a mobile service, once it manages to scale down the kit needed.
Davies added: "The main challenges are having a suitable flat surface and also the correct lighting because the camera needs to see the target correctly." As a result, a longer term option could involve a mobile self-levelling platform that cars can be driven onto, Davies claimed.
The windscreen repair and replacement firm is currently carrying out static calibrations in six sites across the country, with a plan to provide a mobile service to its customers, following its move to make all of its fittings mobile based on feedback from customers. Dynamic tests, meanwhile, will be possible countrywide by the end of 2015.
Why you need to recalibrate a windscreen
Windscreens have gone from being a simple sheet of glass in years gone by to an integral part of a car's technology, often featuring heating elements and facilitating the use of sophisticated safety systems that are reliant on a range of cameras and sensors.
And this is ignoring the future prospect of a windscreen becoming a car's dashboard, displaying a raft of live driving information and even satnav instructions.
However, replacing a windscreen can throw all of these systems out of kilter if they're not recalibrated to work with new glass, which could stop the associated safety kit from working properly and could even cause the systems to misread the road ahead and potentially activate when they shouldn't or fail to compensate for approaching hazards.
Kit that relies on a precisely fitted windscreen includes automatic braking systems, active cruise control that maintains a safe distance behind the vehicle in front, pedestrian-detection systems, traffic sign recognition, lane-departure warnings and even automatic windscreen wipers and headlights, which activate by reading the light and rain levels through the glass.
With cameras offering a wider range of abilities than individual sensors, Chris Davies - head of technical superiority at Belron, Autoglass's parent company - predicts that cameras will be used more and more heavily as cars move towards being fully autonomous, meaning that an increasing number of vehicles will need to be recalibrated following a windscreen replacement.
What 'static calibration' and 'dynamic calibration' involve
Autoglass has trained 125 of its technicians in how to carry out calibrations and invested several hundreds of thousands of pounds in calibration kit, which the company's operations and supply chain director says is "more than anyone else in the industry".
Static calibration - which is currently available in Birmingham, Leeds, Norwich, Rochester, Warrington and Watford - involves a car being parked on a mat in front of a carefully set-up vertical board, which lets the technician check whether the alignment of advanced driver-assistance systems (ADAS) kit has been shifted in the windscreen swap process.
Dynamic calibration, however, requires technicians to drive a car on public roads, with the camera logging a certain amount of 'road furniture' to ensure that it angled properly.