Engine house

The unveiling of an English Heritage Blue Plaque in London’s Bloomsbury seems an unlikely time and place to discuss the latest advances in engineering technology.

But as the plaque is for Sir Harry Ricardo, founder of automotive consultants Ricardo and pioneer of the internal combustion engine, it is in fact highly appropriate. Sir Harry developed the single-cylinder variable compression engine and the concept of toluene (later octane) numbers for rating fuels. During World War II he also helped Sir Frank Whittle with the design of the combustion chambers and fuel control system for his jet engine, and developed an oxygen enrichment system for the Merlin engines of the RAF’s Mosquito night fighters, which transformed their ability to intercept incoming bombers.

So Ricardo the company was founded on cutting-edge engine R&D and this work continues today, according to its chief executive-in-waiting and managing director of international operations, David Shemmans. The company carries out what it describes as ‘technology roadmapping’ in an attempt to forecast future trends in the automotive industry and decide where to focus its R&D, he said.

‘We’ve put a lot of research into improving the carbon dioxide and NOx performance of diesel engines over the last couple of years, so we now have technologies that can meet Euro V legislation ahead of the game,’ said Shemmans.

Ricardo has built a demonstrator vehicle with a 1.9-litre 16V diesel engine, which it claims meets the Euro V legislation, due to be outlined this autumn and to come into force in 2010, without impacting on driveability or performance. Although not yet defined, the legislation is expected to be tough, possibly limiting diesel engine NOx emissions to the Euro IV petrol engine levels of 0.08g/km.

‘We are really homing in now on very low levels of emissions, almost at the level where the measurement techniques are as challenging as the emissions control systems themselves,’ said Shemmans.

The project was supported by the Dutch Ministry of Housing and the Environment and Fiat-GM Powertrain, which provided the C-segment car used in the programme. The engine has an increased rate of exhaust gas recirculation (EGR), and a lower compression ratio to promote premixed combustion, while the company’s engineers made small geometry changes to the combustion bowl. The engine produces NOx emissions of 0.08g/km, and with the addition of a Lean NOx trap this is reduced further to 0.065g/km.

The company is taking the demonstrator around the world presenting it to car makers. ‘We’ve got some very good technologies meeting some of the aggressive targets without aftertreatment in many cases, which has got to be the name of the game because as soon as you start putting aftertreatments on to diesels you incur additional costs.

‘If you look at the technology to meet emissions legislation there are many ways of doing it, but the real challenge is how to do it in a costeffective way so that the car companies can make money. Just throwing technology at it isn’t the answer,’ said Shemmans.

In petrol engine research, the company is focusing on size reduction, turbochargers and direct injection technology.

Ricardo has also been working on a number of hybrid vehicle projects. These include a mild hybrid demonstrator developed with Valeo, called i-MoGen, in which a two-litre diesel engine was replaced with a 1.2-litre diesel and an electric motor. This resulted in 28 per cent fuel savings.

More recently the firm has been involved in a DTI-funded project with Ford to develop a Transit micro-hybrid, called HyTrans, in which the engine shuts down when the van is stopped in traffic. This eliminates fuel wastage during idling and reduces emissions, while some of the power is recovered through regenerative braking.

Finally Ricardo is involved in the Department for Transport’s Ultra Low Carbon Car Challenge, and is developing a full hybrid car with PSA Peugeot Citroën and Qinetiq. The £3m Efficient-C project is developing a C-segment passenger car, based on a   Citroën Berlingo with a highly efficient parallel hybrid powertrain.

Hybrids have faced a certain amount of criticism recently for their added cost and complexity, but Shemmans believes their popularity in Europe will rise. ‘In terms of complexity, I come from an electronics background and my view is that electric transportation and electric-driven powertrains are the purest form, and are simpler than a combustion engine that involves combustion, mechanics and electronics.

‘Blending the two together is complicated, but no more complicated than actually controlling the detailed in-cylinder combustion on a diesel engine,’ he said.

While engine research remains a major focus for Ricardo, just as it was in Sir Harry’s time, the company is also increasing its investment in areas such as electronics and active safety technologies. The latter is likely to increase in importance as car ownership in countries such as China expands. While there are 40,000 road-related deaths in western Europe each year, and a similar number in North America, there are 160,000 road-related deaths in China, in a vehicle population only a 20th the size, said Shemmans.

The company is investigating technologies such as active steer, steer- by-wire, active braking and collision avoidance. ‘We believe the technology is readily do-able. We certainly need to increase the processing power on-board the vehicle to make it happen in real time, but that’s well within our capabilities.’

The first step in Ricardo’s move into active safety is its torque vectoring technology, which works with a vehicle’s ABS system and actively transfers torque to individual wheels as it is needed. By increasing the rotational speed of one axle or an individual wheel, it allows the car’s handling to be altered in real time, and provides greater control during slippy conditions or when going into skids. ‘It’s more than just controlling the braking of the wheels, but actually controlling the torque split.’

The company believes the torque vectoring technology will prove particularly useful in SUVs, given the public’s concerns over how far their high centre of gravity and larger size affect their dynamic stability. The firm has built a demonstrator based on a BMW X5 SUV, which it has been presenting to car makers and Tier 1 suppliers, and during late February and early March this year the vehicle was put through its paces on a frozen lake at Arjeplog in northern Sweden. This cold climate testing allowed the company’s engineers to further develop the system callibration and control strategy, and the car’s turn-in response and yaw stability were improved.

Ricardo is already in discussions with car makers over a number of programmes to introduce aspects of the technology to vehicles. But ultimately it could form part of a wider safety system connecting the car with the road, said Shemmans.

‘If you link it in to telematics and road-sensing technology you can imagine a scenario where rather than the driver handling a situation, if the vehicle sensed it was about to go into a collision it could aid the driver by steering around and keeping the car stable.’