TRW Automotive is one of the world’s largest suppliers of electric steering systems. Its steering system product range includes power and manual rack and pinion steering gears, linkage systems and components, electrically-assisted steering systems, such as electrically powered hydraulic steering and electrically powered column and belt drive steering systems. The company serves the OE and aftermarket. In this interview, Matthew Beecham talked with Charlie Cregeur, director of product planning, TRW Automotive about the company’s latest developments in the electric steering arena.

just-auto: As I understand it, Ford is increasingly using electric steering in its models not just to enhance driving comfort and improve fuel economy but open the door to driver-friendly features such as parallel parking assist.  Could electric steering technology act as catalyst for a number of other driver-enhanced features? How do you see the market evolving?

Electrically Powered Steering (EPS) opens the door for many additional features that can be added via the steering system.   Parallel park is one such feature and there are several others including Lane Keep Assist, Lane Guide, side wind compensation, nibble suppression and vehicle stability enhancements (in conjunction with the braking and in some cases passive restraints systems).  The market for these features is expected to grow as EPS fitment becomes more standard and certainly as fitment reaches into the high end cars and SUV markets.

just-auto: I guess EPS systems are pushing hydraulic steering-assist systems off the road. How do you see the hydraulic steering sector evolving over the next few years?

Hydraulic Powered Steering (HPS) systems are in fact in decline in both North America and Europe.  We still see some modest growth in HPS in emerging markets such as China; however those markets over the longer term will also move to full electric steering as market pricing for EPS matures and scale is achieved.

just-auto: If EHPS systems are a bridging technology, the question is how long do you define that transition period?  Will that period reach into 2015 or 2020 or will it end in two years time?  I guess it depends on the platform that you have been introducing that technology? 

Electrically Powered Hydraulic Steering (EPHS) fitment rates are reducing, however the market still remains interested in this technology as a cost effective way to support lower volume platforms requiring fuel economy improvements and CO2 emission reductions.   Hybrid Electric Vehicles (HEVs) are a good example - a conventional platform with an HEV variant can use EPHS on both types.   There is CO2 emission legislation pending for light commercial vehicles in Europe that will be another avenue for additional EPHS fitment.  

just-auto: Is there an appetite for expensive EPS in some emerging markets such as Eastern Europe, India and China? I guess in terms of functionality then I would presume that that there is. However, I would imagine that you have to consider the robustness of the application and the workshops in the different emerging markets and whether or not electric components might be a challenge for the workshops.  How do you see this application being used in emerging markets?

Emerging markets like China, India, Russia and Brazil all desire the benefits EPS offers.  In the case of the first three, it comes down to affordability compared to traditional HPS/EPHS systems.  Brazil is a market largely driven by follow sourcing from Europe vehicle manufacturers.  China will be a leader in localization and volume ramp up of EPS in the coming years.  In all these emerging markets, one of the key success factors will be the ability to find and develop local suppliers with the appropriate skills and process controls to make components for EPS systems.

just-auto: Some analysts estimate that by 2015, we could expect the European steering market to see fitment rates of 25-30% HPS 55-65% EPS and 5-10% EHPS.  How do you see the market growing over the next five years? 

Our analysis indicates the Europe market to be closing in on 80% EPS fitment for light vehicles by the 2015 time horizon.  It is reasonable to assume there will always be HPS fitment for small volume programs and specialty vehicles where the development cost to launch an EPS system is not practical, or in some cases EPS will not package or is not electrically powerful enough.   As noted previously, the opportunity for additional EPHS fitment for light commercial vehicles exists if the pending CO2 legislation is ultimately passed.

just-auto: While some people see an even stronger link with advanced driver assistance systems, others believe that this may not be before the link braking, steering, and suspension is mature in production; developments are taking place for certain future cognitive safety features.  What is your view on this link?

There is progress in both areas.   Steering integration with Driver Assist Systems (DAS) is progressing, albeit at a rate commensurate with radar and camera fitments and those are largely driven by net cost to the platform as well as what can be sold as marketable features.   At the same time, steering integration with other chassis systems is also progressing.   TRW’s advanced safety, algorithm expertise and integration capabilities allow us to participate in both areas.   It comes as no surprise that the chassis integration part can go more rapidly because of the existence of the enabling hardware; and with the addition of smart algorithms in the braking controller it is quite practical to send signals to the steering system as part of an overall stability improvement solution. 

just-auto: As I see it, steer by wire is still an advanced technology with limited application potential. Sure, you can prove and realise all sorts of advanced features with it but to bring it into the vehicle will cost the OEM an immense amount of money.  So I guess the question here is: will the end customer be willing to pay for it if he / she could get nearly the same functionality with an AFS and EPAS combined?

Steer-by-wire is certainly constrained by the hardware redundancy costs necessary to ensure a robust vehicle safety case.  Active Front Steer continues to be an alternative used by premium car makers to access those enhanced features without the added cost of full redundancy.   Until the time comes that the cost of those redundancies is driven to below what an AFS solution can offer, full steer by wire is likely to remain an advanced concept.  For clarity, it is important to note that TRW and certain competitors have steer-by-wire know-how.  The constraint is the cost of the redundant hardware.

Whether or not end consumers be willing to pay a premium to get the other features AFS offers is difficult to answer.   Typically advanced features like the addition of DAS radar or camera can be sold as an options package on the vehicle.   Benefits of adding radar to offer Adaptive Cruise Control or a camera to add Lane Guide - or both sensors to enable Automatic Emergency Braking - are more easily understood benefits to a car buyer.   AFS versus steer-by-wire is not as easily differentiated by the average car buyer.

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