Tire-pressure monitoring system
[1] A TPMS reports real-time tire-pressure information to the driver, using either a gauge, a pictogram display, or a simple low-pressure warning light.
This functionality first appeared in luxury vehicles in Europe in the 1980s, while mass-market adoption followed the USA passing the 2000 TREAD Act after the Firestone and Ford tire controversy.
Mandates for TPMS technology in new cars have continued to proliferate in the 21st century in Russia, the EU, Japan, South Korea and many other Asian countries.
[2] Aftermarket valve cap-based dTPMS systems, which require a smartphone and an app or portable display unit, are also available for bicycles,[3] automobiles, and trailers.
The following year (2000), Renault launched the Laguna II, the first high volume mid-size passenger vehicle in the world to be equipped with TPM as a standard feature.
The Firestone recall in the late 1990s (which was linked to more than 100 deaths from rollovers following tire tread-separation), pushed the United States Congress to legislate the TREAD Act.
The Act mandated the use of a suitable TPMS technology in all light motor vehicles (under 10,000 lb (4,500 kg)), to help alert drivers of under-inflation events.
After the TREAD Act was passed, many companies responded to the market opportunity by releasing TPMS products using battery-powered radio transmitter wheel modules.
These are most often first generation, purely roll-radius based iTPMS, which ensure that run-flat tires are not used beyond their limitations, usually 80 km/h (50 mph) and 80 km (50 miles) driving distance.
First-generation iTPMS systems are based on the principle that under-inflated tires have a slightly smaller diameter (and hence higher angular velocity) than a correctly inflated one.
Second generation iTPMS can also detect simultaneous under-inflation in up to all four tires using spectrum analysis of individual wheels, which can be realized in software using advanced signal processing techniques.
As iTPMS do not involve any additional hardware, spare parts, electronic/toxic waste, or service (beyond the regular reset), they are regarded as easy to handle and customer-friendly.
Although the systems vary in transmitting options, many TPMS products (both OEM and aftermarket) can display realtime, individual tire pressures whether the vehicle is moving or parked.
Some sensors utilise a wireless power system similar to that used in RFID tag reading which solves the problem of limited battery life.
When mounted on the inside of the rim, they are no longer easily accessible for battery change and the RF link must overcome the attenuating effects of the tire, which increases the energy need.
The significant advantages of TPMS are summarized as follows: Further statistics include: The French Sécurité Routière, a road safety organization, estimates that 9% of all road accidents involving fatalities are attributable to tire under-inflation, and the German DEKRA, a product safety organization, estimated that 41% of accidents with physical injuries are linked to tire problems.
[citation needed] The European Union reports that an average under-inflation of 40 kPa produces an increase of fuel consumption of 2% and a decrease of tire life of 25%.
[citation needed] In 2018, a field study on TPMS and tire inflation pressure was published on the UN ECE Working Party on Brakes and Running Gear (GRRF) homepage.
Main findings are that TPMS fitment reliably prevents severe and dangerous underinflation and hence yields the desired effects for traffic safety, fuel consumption and emissions.
In the early 2000s, numerous traffic accidents such as rollovers and tire blowouts occurred due to insufficient air pressure level.
