By Candace Stuart
Small Times Senior Writer
Feb. 15, 2002 — A U.S. congressional act that calls for tire monitor standards, which involves small technology, appears to be stuck in a political quagmire between federal regulators and the Bush administration.
The disagreement revolves around the Transportation Recall Enhancement, Accountability and Documentation Act, better known by its acronym, TREAD. It calls for automakers to install tire pressure monitoring systems in their 2004 models. In the meantime, some automakers already are incorporating microsystems into their tire systems to monitor pressure and temperature.
But if the White House’s Office of Management and Budget (OMB) prevails, a competing approach that gauges pressure by comparing the rotation of tires may win out. That could
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| Cycloid’s AutoPump ensures all tires are properly inflated. It uses tempera- ture and pressure sensors made by SensoNor to monitor tires and inflates them automatically through a wheel- mounted pump. |
U.S. Department of Transportation spokesman Tim Hurd said that federal regulators have no timetable for finalizing the rules. “It’s a regulatory process; there are always reviews,” he said. Typically the National Highway Traffic Safety Administration (NHTSA) and the OMB swap drafts and reviews before finalizing regulations. “This is not abnormal.”
The drafts and reviews are not made available to the public, according to Hurd.
Lawmakers passed the TREAD Act in 2000 after getting reports that Ford Explorers rolled over, sometimes fatally, when the treads on their underinflated Bridgestone/Firestone tires separated. The act calls for the installation of monitoring equipment to be phased in on all new vehicles, starting with the 2004 models. NHTSA was to determine what constitutes monitoring by the end of November 2001.
The Wall Street Journal reported Wednesday that NHTSA submitted a draft proposal to OMB in December. It didn’t specify when OMB responded.
The OMB also issued a news release Wednesday stating it favored what is called indirect tire pressure monitoring systems. NHTSA had recommended phasing in systems that monitor tire pressure directly.
Indirect systems typically are incorporated into a vehicle’s antilock braking system. They use wheel speed sensors to track the rotation of each wheel and detect deflation through rotational differences. Rotational speed increases as tire pressure decreases.
The indirect approach is less expensive and easier for automakers to incorporate, NHSTA said in a detailed analysis. But it said the indirect system also fails to detect pressure loss if all tires lose pressure at similar rates, fails to detect small pressure losses and cannot pinpoint which of the four tires are failing. Also, it said, vehicles need to be in motion for it to work, it takes minutes to detect underinflation and it’s inaccurate if the vehicle is being driven at high speeds or on rough roads.
Underinflation is a safety concern because tires kept below their ideal pressure heat up, making them prone to blowouts. Underinflation also adds to tire wear and lowers gas mileage. All tires lose pressure gradually and need to be inflated periodically.
Direct systems use sensors that measure pressure losses, even small ones, directly, instantly and on all road conditions. If operated by battery and linked to a display by RF devices or other technologies, direct sensors can alert drivers even when the car is still, and specify which tire is failing. But NHTSA points out that direct systems cost more, especially when display equipment and software are factored in. Also, it said, the sensors require a power source and are not as robust as indirect systems.
General Motors Corp. invested in the indirect approach in its more than 1.5 million vehicles equipped with antilock brake systems (ABS). Bosch is a leading supplier most of these ABS components.
A number of European, Japanese and American automakers have added direct sensors to their high-end vehicles. They are working with several small tech suppliers and systems designers, including SensoNor in Norway, Schrader Electronics in Northern Ireland, SmarTire Systems Inc. in British Columbia, BERU AG and Siemens AG in Germany, and Motorola Inc. and Cycloid Co. in the United States.
“The competitor for us is probably more NHTSA than anyone else,” said Grant Renier, Cycloid’s chairman and chief executive. Cycloid provides a device called the AutoPump, which ensures all tires are properly inflated. It uses temperature and pressure sensors made by SensoNor to monitor tires and inflates them automatically through a wheel-mounted pump.
Ford Motor Co. is negotiating with Cycloid to include the AutoPump on its Lincoln Town Car and other 2005 platforms — a year later than originally planned. Ford also awarded BERU AG and its U.S.-based partner, Lear Corp. a contract to supply a direct system for monitoring tires on it future Explorer sport-utility vehicles. BERU specializes in microsystems sensors and Lear in electronics.
OMB’s regulatory administrator, John Graham, was not available for comment Thursday. But in its news release, the OMB said it based its preference on safety and cost concerns. It said NHTSA’s proposal would serve as a disincentive for automakers to install antilock brakes, a safety feature that is not required under law. It said its proposal, which would allow automakers to exceed the standards by using the direct system if they wanted, would lower the cost of installing antilock brake systems by 22 percent.
Upgrading to the direct system is an option some automakers may consider, said Charlene Krepiakevich, spokeswoman for SmarTire. SmarTire’s products combine MEMS sensors and transmitters in tire monitors for trucks, industrial equipment and automotive suppliers. Even if the OMB succeeds, NHTSA’s analysis gives automakers and their customers information for future decisions.
“We’re delighted that they looked at it (direct systems) and said it can be done,” she said. “NHTSA did an excellent job at evaluating the technologies.”
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CONTACT THE AUTHOR:
Candace Stuart at [email protected] or call 734-528-6290.