Driver information delivery is focused on improving the human-machine interface (HMI). The instrument cluster is the traditional delivery method and is evolving to meet driver information needs. Clusters are gaining graphics capabilities and configurable displays are providing design and functionality flexibility. While the trend is a combined cluster design of analog and graphics displays, the ultimate configurable display may prove to be the head-up display (HUD).
Whether in a traditional instrument cluster package or an HUD, the configurable display HMI approach improves the ability to control the flow, prioritization and time of information being delivered to the driver.
A driver spends more time viewing the instrument cluster than any other part of the interior. Therefore, driver information must enhance safety, make transportation more efficient, driving more enjoyable and drivers more productive. Configurable displays provide designers with freedom to style the instrument cluster to better fit the interior vehicle style and alleviates the need to package as many non-critical components in the instrument cluster.
Currently, liquid crystal displays (LCDs) are the predominant trend in configurable display electronics and are used in two formats — dot matrix and thin-film transistor (TFT) displays.
Dot matrix displays, as seen in the Mercedes Benz E instrument cluster, allow features to be differently arranged. They are being used to differentiate driver information delivery between low/mid/high feature content vehicles by populating or depopulating information being displayed.
TFT displays have become prominent in secondary displays, often located in the center stack. As seen in the Audi A8 instrument cluster, TFT display material gives images and graphics a higher definition, has fast image switching times, good viewing angles and can be produced in large surface sizes. It is a more expensive approach, but TFT material prices have continued to decrease due to higher sales volumes and improvements in manufacturing technology.
Dot matrix and TFT displays can be found in the center of the instrument cluster. Positioning this driver information delivery solution between traditional analog gauges reduces glance times, while maintaining a sense of symmetry within the instrument cluster.
One step beyond the centered display is placing driver information in front of the driver in the optimum viewing area using HUD. In the future, HUD systems will continue to become more cost effective, dissipate less heat, more easily packaged, more reliable and better integrated into the vehicle's overall brand character. BMW has moved aggressively in the HUD direction and Siemens VDO Automotive is working with OEMs around the world on HUD solutions for next-generation vehicles over the next three years.
Configurable display technology has its challenges.Extremely cold temperatures affect dot matrix displays' delay switching times, forcing critical, immediate driver information to be communicated by other means. Also, delivering sharp color and contrast over a large viewing angle is a limitation of LCD displays. This challenge can be overcome when the display is in the instrument cluster.
The future of configurable display technology is being driven by automotive electronics and is getting brighter as added functionality and government regulations increase in-vehicle information. They have become the norm for most new domestic, European and Asian vehicles.
Active matrix displays are a cost-effective solution as display purchase volumes grow and styling and intelligent information delivery advantages are realized. Within the next two or three years, those who have not adopted reconfigurable displays will become hard pressed to control driver information delivery. Driver distraction in the form of information overload is becoming a reality.
ABOUT THE AUTHOR
John G. Sanderson is the president and chief executive officer of Siemens VDO Automotive Corp. He has the responsibility for the global automotive electronics supplier's North American business.