Jaguar X-type ergonomics

Jaguar applied extensive data on the human form to achieve ergonomic efficiency in the design of the X-type.

Achieving ergonomic efficiency has been a particular focus for the Jaguar X-type design and engineering teams. The car has been designed to accommodate a wide range of drivers, from a 95th percentile 1.9-m (6.3-ft) tall male with a mass of 106 kg (234 lb), to a 5th percentile 1.5-m (5-ft) tall female with a mass of 38 kg (84 lb), as well as for people outside those parameters. Because the car is a compact sport sedan, the challenge to achieve this efficiency has been considerable and the company is using a lot of internationally sourced data.

Mark Humphreys, one of Jaguar's senior ergonomics specialists, said X-type seat and steering wheel adjustments are extensive and that the position of all major and minor controls has received particular attention. But there is more to the work of the ergonomics teams than that. To achieve requirements, the company applies extensive data on the human form, including hand sizes. Jaguar studied 56 anthropometric dimensions for hands, including width, depth, circumference of fingers and thumb, grip widths, and wrist sizes. "These measurements may vary widely across the world's population," said Humphreys. Jaguar has also discussed ergonomic issues with BAE Systems' specialists at that company's Warton military aircraft facility in northwest England. BAE Systems is a partner in the multinational Eurofighter program.

All major and minor controls received extensive attention in the ergonomic design of the X-type interior.

"We have discussed ergonomics with BAE as a discipline rather than anything specifically production related," said Humphreys. "A lot of ergonomic work is psychology based, and members of the ergonomics team at Jaguar have studied psychology at some level."

Originally, ergonomics was about designing to achieve maximum efficiency and to avoid physical discomfort or pain in the working environment. But now, it is far more subtle and even extends to the ideal weighting of a car door handle and the tactility and sound of switch operation.

Jaguar has a Women's Committee that addresses the particular ergonomic problems females may experience when driving a car or using its systems, including carrying children and accessing the trunk. Women do not have "massively different" priorities when using a car to those of males, according to Jaguar, and often ergonomic problems are smaller stature issues rather than just female. Ford also uses a Women's Committee to advise on design and ergonomics. Jaguar can tap into that data where it is appropriate to a premium brand. Both companies underline the importance of considering the widest possible span of ergonomic issues from the earliest concept sketches of a new car.

- Stuart Birch

Delphi brings e-steering system to U.S.

Delphi's E-Steer Electric Power Steering System uses three primary inputs—steering wheel torque, steering wheel position, and vehicle speed— to determine via an electronic-control module the magnitude and direction of steering assist.

In January, Delphi announced plans to produce the E-Steer Electric Power Steering System at the Delphi Saginaw Steering Systems' Buena Vista complex in Michigan as part of a brownfield redevelopment project. The first U.S. production of E-Steer begins after factory renovations to 37,000 m² (400,000 ft²) are completed. Factory alterations also will address process improvements for other steering and driveline products.

E-Steer uses three primary inputs—steering wheel torque, steering wheel position, and vehicle speed—to determine via an electronic-control module the magnitude and direction of steering assist. Paul Tosch, Delphi Saginaw Steering Systems President and Delphi Automotive Systems Vice President, expects by 2005 more than $1 billion in annual sales for Delphi's electric steering systems, including rear steering systems.

E-Steer is standard equipment on Europe's 2000 Fiat Punto, and optional equipment on Volkswagen's 2001 Lupo 3L TDI.

- Kami Buchholz

Smarter glow-plugs via AFL

Advances in diesel-engine technology in terms of improved emissions, higher performance, and reduced noise have transformed the diesel's image and applications. Mercedes-Benz, Audi, and BMW each has a large capacity diesel engine fitted to its top models. The Mercedes S-Class's V8 turbodiesel technology includes a new generation of smart, solid-state output controller units to regulate the power of its glow-plugs in the pre-heat phase as well as during engine operation. Produced by AFL Stribel, part of AFL (Alcoa and Fujikura), the controller responds to signals from the engine-management system to switch on the glow-plugs, but otherwise acts independently. By controlling the electrical power of the glow-plugs, the new unit enables the diesel to be burnt more thoroughly, improving the energy efficiency of the car and cutting the levels of exhaust pollution, according to AFL Stribel. The car also benefits from a major reduction in pre-heat time and cold-start phase.

The controller communicates with the engine-management system via a one-wire serial datalink, exchanging information about the status of each glow-plug and system parameters such as voltage. The glow-plugs themselves can be used as an indicator to give the system information about the temperature within the combustion chamber. Self-test and analysis functions provide a full diagnostics interface that fulfills OBD requirements and allows the individual control of each single glow-plug. Additional routines built into the hardware and software of the unit protect the communications link against failure.

Integrated safety features are programmed into the unit, with online protection for shorts, overloads, and open circuits. If one glow-plug should fail, only that one would be disconnected. No additional fuses are required. The control unit is fully software configurable.

- Stuart Birch