Driver assistance technologies aim to make the vehicle capable of perceiving its surroundings, interpret them, identify critical situations, and assist the driver in performing driving manoeuvres. The object is, at best, to prevent accidents completely and, at worst, to minimise the consequences of an accident for those concerned. Matthew Beecham talked with executives of TRW about their driver assistance technologies and how the global market is shaping-up.
just-auto: Radar-based safety technologies such as advance collision warning and blind-spot detection are becoming common place as optional equipment on new vehicles. While the possibilities to “assist the driver” seem endless, is there a risk of information overload?
TRW: As Driver Assist Systems (DAS) are designed to help a driver in potential emergency situations, any warnings given by the system must be clearly understandable to the driver in order to allow them to react quickly and correctly in a potential “high-stress” situation.
Like Electronic Stability Control, some Driver Assistance Systems can operate autonomously and therefore no input needs to be provided to the driver. For example with an Automatic Emergency Braking system, data from a forward looking radar and video camera can be combined to provide a real time image of the road ahead. If a potential collision situation is detected and the driver does not react sufficiently to steer or brake to avoid the collision, the AEB system can automatically apply the vehicle brakes to help mitigate the impact.
Other DAS systems provide feedback to the driver, but they are designed to actively ‘coach’ the driver to help avoid a critical situation – providing subtle feedback when they need to be more alert. For longitudinal support this could be a virtual ‘brake pedal tap’ or a quick deceleration of the vehicle if it is deemed to be approaching the vehicle in front too fast. This type of feedback is intended to instinctively warn the driver that they need to brake, and coaches the driver to automatically look forward. Alternatively, for lateral support, TRW’s lane guide technology provides a torque overlay to the steering to gently guide the driver back towards the centre of the lane if the vehicle is about to inadvertently leave its lane on a highway – rather than simply sound a warning tone that the driver needs to correctly interpret before responding.
I guess that there is a fine line between helping the driver steer clear from trouble and doing too much?
In Europe in 2009 there were almost 35,000 road fatalities and 1.5 million injuries, the majority of which were due to driver error – and this is what we are trying to address. The driver needs to of course maintain control of the vehicle, but the point of the DAS system is to intervene when the driver is not fully attentive and/ or in full control of their vehicle, acting as a “safety net” in the same way that ESC does.
DAS systems can be designed to prevent over-reliance on the technology – for example, a lane keeping system can sense when the driver has taken their hands off the steering wheel and send audible and visual warnings to the driver to retake control of the vehicle.
Now that the National Highway Traffic Safety Administration has made collision warning and lane departure alert part of the New Car Assessment Programme requirements for a five-star safety rating, I guess that the market for such technology in North America will grow?
Until recently, the DAS market in North America has been led by European and Japanese premium vehicles, but the domestic automakers are catching-up quickly and now starting to take the lead in terms of bringing DAS technology to mass-market vehicles.
Historically, vehicle manufacturers have approached the North American market cautiously due to potential liability concerns (for example, they have implemented warning only DAS systems in the US market compared to fully active systems in Europe or Japan). There has been a significant increase in activity in the industry over the last year however, as many vehicle manufacturers selling in the US market are actively developing DAS systems to meet the NCAP Lane Departure Warning (LDW) and Forward Collision Warning (FCW) requirements.
To what extent does driver acceptance of radar safety systems vary from one geographical market to the next?
The DAS market originated in Europe, with Japan following and then the US (although as the US market is more cost sensitive, adoption rates have been lower). There has been no significant difference in driver acceptance across these markets – the bigger challenges have been raising consumer awareness of DAS systems capabilities to stimulate demand, along with making the systems affordable for mass-market vehicle buyers.
For some time, advanced driver assistance systems were the sole preserve of the luxury vehicle class yet nowadays features such as adaptive cruise control and lane departure warning systems are being offered on the Ford Focus. How do you see the roll out of such ADAS technologies across all vehicles in Europe?
DAS technologies are becoming increasingly common in the European mass-market ”C” and “D” segments – for example TRW’s Lane Keeping camera system in the Lancia Delta hatchback and ACC radar system in the VW Passat – but do not appear in the “A” and “B” segments today.
We expect to see a wider rollout of DAS technology in European “C” segment vehicles in the next 2-3 years, as new product launches such as TRW’s 24GHz forward-looking radar continue to drive down the cost of DAS technology. Other European market drivers include potential regulations for DAS systems following the truck and bus regulations already in place, and the introduction of insurance incentives – which would assist in bringing DAS even to the lowest cost “A” and “B” segment vehicles.
To what extent has the trend toward global platforms enabled new technologies to be introduced in low-tech markets?
The trend for global platforms certainly opens up opportunities for the implementation of DAS technologies in new and emerging markets; global OEMs can develop DAS systems for their home markets, and then roll out and adapt their offerings to meet regional requirements as the new markets develop.
For this reason, it’s important that suppliers can offer ‘scalable’ product portfolios in order to suit the needs of different markets. TRW offers a number of scalable technologies including its video cameras, 24GHz radar sensors and scalable airbag control units.
We are experiencing strong demand in China for Adaptive Cruise Control (ACC) – as high tech features are desirable on premium import vehicles.
As we understand it, traffic sign recognition is a relatively new function for camera platforms. While this functionality starts with speed monitoring, could it be developed to embrace other derivatives?
In addition to monitoring existing speed limits, Traffic Sign Recognition can also be used for the detection of “Give Way” and “Stop” signs – which can be linked to AEB systems to automatically slow or stop a vehicle if it would unintentionally pass these signs.
With the improvement of ADAS, I guess map data and positioning information of navigation systems require more accurate and extensive location information? e.g. detailed road shape such as curvature, gradient, number of lanes, crossing, lamp, and so on.
Improving the accuracy of map data can provide enhanced safety through features such as curve speed warning: if approaching a tight bend too fast, the system can warn the driver to slow down, and automatically brake the vehicle to reduce speed if the driver does not respond and there is a risk of the vehicle running off the road.
An enhanced map database can be compared with (real-time) camera lane data to confirm road geometry, but can also assist DAS systems by providing advanced information of road geometry changes (e.g. curves ahead beyond the range of a camera), or intersections to help the camera more easily determine the actual environment in front of the vehicle. This can also improve the long range tracking performance of an ACC or AEB radar, for example by helping to confirm if vehicles ahead are changing lanes or simply entering a corner.
Could you give us an idea of the type of technical advances you are making in the area of navigation-based ADAS? i.e. maybe in terms of the fusion technology of radar and vision sensors which complements the accuracy of ADAS.
TRW is integrating digital map data with its ‘Active Control Retractor’ seatbelt system – helping to pretension the seatbelt and pull the driver into an optimal position in relation to the airbag enclosure if a vehicle is approaching a curve too quickly. TRW can also use GPS data together with its radar and camera sensors to enhance the performance of automatic braking systems. By using the digital map data, the ESC system would know that a bend is coming up long before the vehicle gets there and can therefore start to brake sooner than with a camera sensor working alone.