Aviation Stack Exchange is a question and answer site for aircraft pilots, mechanics, and enthusiasts. It only takes a minute to sign up.
Sign up to join this community
In this question the sensors to measure the tyre pressure are described.
But how do such sensors receive the electrical power they need, and how are the signal values transmitted back to the relevant computer systems?
Since the wheel rotates, one would presume that transferring power and data electrically with the reliability needed for aviation use would pose specific demands on the technology.
For small planes simple systems can be installed that fit on the inflation tubes and replace your standard cap. They use small batteries in the sender units and a little read out.
It looks like Boeing gets their tire pressure/break temp systems from Crane Aerospace. The latest and greatest systems are all wireless
The Crane 777 Tire and Brake Monitoring System (TBMS) provides continuous real-time monitoring of aircraft tire pressure and brake temperature. The design incorporates our SmartStem® wireless tire pressure sensor with integrated fill valve. The SmartStem uses sensing technology with triple redundant sensing channels to provide high reliability and accuracy. The Crane TBMS replaces TPMU and BTMU units (from the legacy system) with a single Tire and Brake Monitoring Unit (TBMU) that interfaces with the existing brake temperature probes. The existing wheel interface unit is replaced with an in-axle transformer and relay transformer hubcap assembly that allow the tire pressure signal to be transmitted magnetically with no physical contact between the components. Retrofit of the Crane TBMS requires no change to the AMC, EICAS, and CMC system interfaces.
That does not shed to much light on how it all works though. Their handheld system is RFID based and presumably their built in system is similar.
