Patent Description:
Tyre pressure monitoring systems (TPMS) typically comprise large and cumbersome sensing modules that must be fitted to a pneumatic tyre of a vehicle. In addition, a driver indicator unit is installed in the vehicle for notifying the driver of the pressures of gas retained in the pneumatic tyres (the tyre pressures).

In such systems, the sensing modules are configured to transmit an absolute value for the tyre pressure of each pneumatic tyre to the driver indicator unit. The driver indicator unit then displays the tyre pressures to the driver. The driver indicator unit also determines whether the tyre pressures are within limits set by one or more tyre parameters and informs the driver if that is not the case. The driver indicator unit therefore requires programming in order to determine the tyre parameters. Typically, this may require a user or fitter of the system to program into the driver indicator unit a number of pressure values based on, for example, the vehicle type, the tyre type, the location of the tyre on the vehicle, the tyre high and low pressure limits, etc. This is complicated, time consuming and is prone to error.

It is a requirement for drivers of fleet vehicles, such as vans, lorries and buses to check tyre pressures daily and before use of a vehicle. Ensuring that such checks are carried out involves significant burden and risk for fleet vehicle operating companies. <CIT> relates to a tire state monitoring device. <CIT> relates to a vehicle wheel monitoring system. <CIT> relates to a tire data collection and communication device. <CIT> relates to a TPMS sensor position setting method.

According to an aspect of the invention, there is provided a tyre pressure sensing module according to claim <NUM>. Also disclosed herein is a tyre pressure sensing module for fitting to a wheel of a vehicle comprising a pneumatic tyre, the sensing module comprising: a pressure sensor for sensing a pressure of a gas retained within the pneumatic tyre; a receiver configured to receive, from a user module, data indicating that the user module is proximal to the tyre pressure sensor; a transmitter configured to transmit to an apparatus, data indicating that the user module has been proximal to the tyre pressure sensor.

Use of the tyre pressure sensing module for determination of completion of a walk around check provides the ability to use an existing sensor arrangement to provide an additional benefit. Tyres of a vehicle are typically located at the corners of the vehicle and if a user visits tyre pressure sensing modules located at the corners of the vehicle, this can be considered a proxy for completion of a walk around check.

Optionally, the user module is proximal to the tyre pressure sensor when it is less than <NUM> away from the tyre pressure sensor, less than <NUM> away from the tyre pressure sensor; less than <NUM> away from the tyre pressure sensor, less than <NUM> away from the tyre pressure sensor or less than <NUM> away from the tyre pressure sensor.

Optionally, the user module comprises a pressure reader module, and wherein the receiver is configured to receive, from the pressure reader module, a request for tyre pressure data indicative of a the pressure of the gas retained within the pneumatic tyre, the tyre pressure sensor further comprising a pressure check register configured to store data indicating that the request for tyre pressure data was received, wherein the transmitter is configured to transmit to the apparatus, an indication confirming whether a tyre pressure check has been carried out based on whether the request for tyre pressure data was received.

Optionally, the transmitter is further configured to transmit the requested tyre pressure data to the pressure reader module.

Optionally, the tyre pressure sensing module is further configured to poll the pressure check register to determine whether tyre pressure data has been requested.

Optionally, the tyre pressure sensing module is further comprising a motion sensor configured to determine whether the wheel is rotating.

Optionally, the transmitter is configured to transmit the indication in dependence on the motion sensor determining that the wheel is rotating.

Optionally, the transmitter is configured to send a positive indication that the pressure reader module has been used if the request for tyre pressure data was received.

Optionally, the transmitter is configured to send a negative indication that the pressure reader module has been used if the request for tyre pressure data was not received.

Optionally, the transmitter is further configured to transmit, to the apparatus, tyre pressure data indicative of a the pressure of the gas retained within the pneumatic tyre.

Optionally, the apparatus comprises the user module and wherein the transmitted data indicating that the user module has been proximal to the tyre pressure sensor is configured to be forwarded to a further apparatus.

According to an aspect of the invention, there is provided an apparatus according to claim <NUM>. Also disclosed herein is an apparatus for use with a plurality of tyre pressure sensing modules, comprising: a receiver configured to receive, from a plurality of tyre pressure sensing modules, a plurality of indications of whether a user module has been proximal to each of the plurality of tyre pressure sensing modules; and a walk around check confirmer configured to determine whether a vehicle walk around check has been carried out based on the received plurality of indications.

Optionally, the user module comprises a pressure reader module and the plurality of indications indicate that the pressure reader module has been used on each of the plurality of tyre pressure sensing modules to check a corresponding tyre pressure, and wherein the walk around check confirmer comprises a pressure check confirmer configured to determine that a vehicle tyre pressure check has been carried out if all of the received indications are positive indications that the pressure reader module has been used.

Optionally, the plurality of received indications includes indications from all tyre pressure sensing modules fitted to a vehicle.

Optionally, the pressure check confirmer is configured to determine that the vehicle tyre pressure check has not been carried out if one or more of the received indications are negative indications that the pressure reader module has not been used.

Optionally, the apparatus comprises on of a driver indicator unit and a user equipment. Optionally, the apparatus further comprises a transmitter configured to transmit data confirming whether the walk around check has been carried out.

Optionally, if the apparatus comprises a the driver indicator unit, the transmitter is configured to transmit data confirming whether the walk around check has been carried out to a server connected to a network, and wherein if the apparatus comprises a user equipment, the transmitter is configured to transmit data confirming whether the walk around check has been carried out to a driver indicator unit and/or a server connected to a network.

Optionally, the walk around check confirmer is configured to control immobilisation of the vehicle based on the received plurality of indications.

According to an aspect of the invention, there is provided a tyre pressure monitoring system for fitting to a vehicle according to claim <NUM>.

Optionally, the tyre pressure monitoring system further comprises a pressure reader module and/or a user module.

According to an aspect of the invention, there is provided a vehicle according to claim <NUM>.

According to an aspect of the invention, there is provided a method according to claim <NUM>. Also disclosed herein is a method for determining whether a vehicle walk around check has been carried out, the method comprising: receiving, by a receiver from a user module, data indicating that the user module is proximal to the tyre pressure sensor; and transmitting, by a transmitter to an apparatus, data indicating that the user module has been proximal to the tyre pressure sensor. <NUM>-<NUM>.

According to an aspect of the invention, there is provided a method according to claim <NUM>. Also disclosed herein is a method for determining whether a vehicle walk around check has been carried out, the method comprising: receiving, by a receiver and from a plurality of tyre pressure sensing modules, a plurality of indications of whether a user module has been proximal to each of the plurality of tyre pressure sensing modules; and determining, by a walk around check confirmer, whether a vehicle walk around check has been carried out based on the received plurality of indications.

Exemplary methods and apparatus are described herein with reference to the accompanying drawings, in which:.

Generally, disclosed herein are tyre pressure sensing modules and driver indicator units that may form part of a TPMS. Exemplary sensing modules disclosed are configured not to transmit absolute tyre pressure values to the driver indicator unit, but to transmit alert signals notifying the driver indicator unit that a value related to the tyre pressure of a wheel is not within limits set by one or more tyre parameters. That is, in
exemplary arrangements, the sensing module is configured to determine whether the value related to the tyre pressure is within the tyre parameters, rather than the driver indicator unit.

The inventor has appreciated that by moving the determination of whether to generate an alert signal from the indicator unit to the sensing module, less data is required to be transmitted and the frequency with which data is to be transmitted from the sensing module to the driver indicator unit is greatly reduced. The sensing module only needs to transmit an alert signal when an alarm is necessary, which can be much simpler and more data efficient than transmitting an absolute tyre pressure value, which other systems typically send every five minutes continuously. This provides benefits in terms of reduced power consumption, which allows the battery of the sensing unit to be smaller for a given time sensing module battery life, reducing the need for replacement batteries, complicated instructions and structures for battery exchange, and enabling a low cost permanently sealed solution. This also has the added benefit of a lightweight sensing module which reduces stresses on the valve stem and prevents any possibility of effecting the wheel balance. Finally, a smaller sensing module is less conspicuous and therefore less liable to be targeted for theft.

In addition, the inventor has appreciated that by moving the determination of alert signals to the sensing module, the burden of programming the driver indicator unit may be removed. Exemplary sensing units may be configured to self-calibrate based on a tyre pressure sensed at the time of fitting the sensing module. The one or more tyre parameters may be calculated by the sensing unit based on the initial sensed pressure.

Further, the inventor has appreciated that it is desirable to ensure that a driver or other operative has completed a walk-around check of a vehicle before use. Such checks may be completed daily, for example. A walk-around check may include a check of the tyre pressures of a vehicle. Wheels are typically located at all corners of the vehicle and it is therefore necessary to walk around the vehicle to check the tyre pressures. In this way, confirmation of tyre pressure checks may be used as a proxy for confirmation that a walk-around check has been completed. More broadly, confirmation that a user, or specifically a user module (which may be a pressure reader module), has been proximal to a tyre pressure sensing module may be used as a proxy for confirmation that a walk-around check has been completed.

<FIG> shows a schematic diagram of a TPMS fitted to a vehicle <NUM>. The TPMS includes a driver indicator unit <NUM> and a plurality of tyre pressure sensing modules 104a-f. The driver indicator unit <NUM> is fitted within the vehicle and in view of the driver. Each of the sensing modules 104a-f is fitted to a wheel 106a-f of the vehicle <NUM> and each wheel 106a-f comprises a pneumatic tyre. The sensing modules 104a-f are configured to sense a tyre pressure of a corresponding pneumatic tyre, as explained in greater detail below. Each of the sensing modules 104a-f is also configured to determine whether an alert signal should be transmitted to the driver indicator unit <NUM> based on the sensed tyre pressure.

The vehicle <NUM> of <FIG> is a lorry or other goods vehicle, but it will be appreciated that the TPMS and any components thereof may be fitted to any type of vehicle, including towed vehicles, having at least one pneumatic tyre.

<FIG> shows a schematic representation of a tyre pressure sensing module <NUM>, which may be a sensing module 104a-f shown in <FIG>. The sensing module <NUM> comprises a transmitter <NUM> and a receiver <NUM>. The transmitter <NUM> and receiver <NUM> may be in data communication with other entities in a TPMS, such as driver indicator unit <NUM>, servers and/or functions in a telecommunications network and is configured to transmit data accordingly.

The sensing module <NUM> further comprises a memory <NUM> and a processor <NUM>. The memory <NUM> may comprise a non-volatile memory and/or a volatile memory. The memory <NUM> may have a computer program <NUM> stored therein. The computer program <NUM> may be configured to undertake the methods disclosed herein. The computer program <NUM> may be loaded in the memory <NUM> from a non-transitory computer readable medium <NUM>, on which the computer program is stored. The processor <NUM> is configured to undertake one or more of the functions of an alert generator <NUM>, an auto-calibrator <NUM>, a parameter determiner <NUM> and a pressure check register (or in some arrangements walk-around check register) <NUM>, as set out below. The sensing module <NUM> also comprises a pressure sensor <NUM>, an LED <NUM>, a motion sensor <NUM> and temperature sensor <NUM> and the processor may be configured to control one or more of these features.

Each of the transmitter <NUM>, receiver <NUM>, memory <NUM>, processor <NUM>, pressure sensor <NUM>, alert generator <NUM>, LED <NUM>, auto-calibrator <NUM>, parameter determiner <NUM>, motion sensor <NUM>, temperature sensor <NUM> and/or pressure check register <NUM> is in data communication with the other features <NUM>, <NUM><NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> of the sensing module <NUM>. The sensing module <NUM> can be implemented as a combination of computer hardware and software. In particular, the alert generator <NUM>, auto-calibrator <NUM>, parameter determiner <NUM> and/or pressure check register <NUM> may be implemented as software configured to run on the processor <NUM>. The memory <NUM> stores the various programs/executable files that are implemented by a processor <NUM>, and also provides a storage unit for any required data. The programs/executable files stored in the memory <NUM>, and implemented by the processor <NUM>, can include the alert generator <NUM>, auto-calibrator <NUM>, parameter determiner <NUM> and/or pressure check register <NUM>, but are not limited to such.

<FIG> shows a schematic representation of a driver indicator unit <NUM>, which may be a driver indicator unit <NUM> shown in <FIG>. The driver indicator unit <NUM> comprises a receiver <NUM> and may also comprise a transmitter <NUM>. The transmitter <NUM> and receiver <NUM> may be in data communication with other entities in a TPMS, such as sensing modules 104a-f, servers and/or functions in a telecommunications network and are configured to transmit and receive data accordingly.

The driver indicator unit <NUM> further comprises a memory <NUM>, a processor <NUM> and a display <NUM>. The memory <NUM> may comprise a non-volatile memory and/or a volatile memory. The memory <NUM> may have a computer program <NUM> stored therein. The computer program <NUM> may be configured to undertake the methods disclosed herein. The computer program <NUM> may be loaded in the memory <NUM> from a non-transitory computer readable medium <NUM>, on which the computer program is stored. The processor <NUM> is configured to undertake one or more of the functions of a display generator <NUM> and a pressure check confirmer (or in some arrangements a walk-around check confirmer) <NUM>, as set out below.

Each of the transmitter <NUM> and receiver <NUM>, memory <NUM>, processor <NUM> display generator <NUM>, display <NUM> and/or pressure check confirmer <NUM> is in data communication with the other features <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> of the driver indicator unit <NUM>. The driver indicator unit <NUM> can be implemented as a combination of computer hardware and software. In particular, the display generator <NUM> and/or pressure check confirmer <NUM> may be implemented as software configured to run on the processor <NUM>. The memory <NUM> stores the various programs/executable files that are implemented by a processor <NUM>, and also provides a storage unit for any required data. The programs/executable files stored in the memory <NUM>, and implemented by the processor <NUM>, can include the display generator <NUM> and/or the pressure check confirmer <NUM>, but are not limited to such.

<FIG> shows a flow chart for a method for monitoring tyre pressure. After a sensing module 104a-f is manufactured, it is in a sleep mode <NUM> during which the pressure sensor <NUM> senses the pressure to which the sensing module is exposed at predefined intervals. In exemplary arrangements, the interval may be in a range from <NUM> seconds to <NUM> seconds and in a specific arrangement may be <NUM> seconds. While the sensing module is not fitted to a pneumatic tyre, the pressure sensor <NUM> will sense atmospheric pressure. The sensing module 104a-f is configured to remain in sleep mode if the pressure sensor <NUM> senses atmospheric pressure.

Before fitting the sensing module 104a-f to a tyre, the tyre should be inflated to the correct pressure. Then, the sensing module 104a-f is fitted to the tyre <NUM> and after completion of the next interval period, the pressure sensor <NUM> senses the pressure of the gas retained within the tyre. This will be a pressure significantly greater than atmospheric pressure, for example, around <NUM> pounds per square inch (approximately <NUM> Bar). The auto-calibrator <NUM> is configured to calibrate <NUM> the sensing unit 104a-f in response to the pressure sensor <NUM> detecting the first pressure that is greater than atmospheric pressure, that is, the first time that a tyre pressure is sensed.

The sensing module 104a-f may comprise a fitment that is configured to allow the sensing module 104a-f to be fitted to a valve of the pneumatic tyre of each wheel. The valve may be a Schrader type valve and may comprise a screw thread. Therefore, the sensing module 104a-f may comprise a corresponding screw thread permitting the sensing module 104a-f to be screwed onto the valve. The fitment may also comprise a valve actuator configured to interact with the valve when the sensing module 104a-f is fitted to allow gas from within the tyre to enter the pressure sensor <NUM>. In this way the pressure sensor <NUM> is able to sense the pressure of the gas within the tyre.

Because the tyre has been inflated to the correct pressure before fitting the sensing module 104a-f, the initial pressure sensed by the pressure sensor after fitting is used to calibrate the sensing module 104a-f. The auto-calibrator <NUM> calibrates <NUM> the sensing module 104a-f by setting a calibrated pressure to be the initially sensed tyre pressure.

The calibrated pressure may remain the same until the sensing module 104a-f is removed from the tyre and the pressure sensor <NUM> senses atmospheric pressure again, after which the sensing module 104a-f is reset and enters sleep mode once again. The reset may be configured to occur when the journey has ended and the pressure sensor <NUM> senses atmospheric pressure. If the pressure sensor <NUM> senses atmospheric pressure during a journey then this may indicate a blowout.

Once the sensing module 104a-f has been fitted to the tyre and has been calibrated, the LED <NUM>, or another visual indicator, is configured to illuminate, for example by flashing a predetermined number of times. This provides a visual indication that the sensing module is operational and has sufficient battery life, without the need to transmit any data to the driver indicator unit <NUM>. In addition, this feature can be used as a sensor check on a vehicle, trailer, caravan etc. that has not been used for a long time. By removing and refitting the sensing module 104a-f, if the user observes the illuminated LED then they can have confidence that the sensor is still working.

Of course, in other exemplary arrangements, the calibrated pressure may be predetermined and programmed into the sensing module 104a-f during manufacture.

The sensing module 104a-f may then undergo a pairing procedure to register the sensing module 104a-f with the driver indicator unit <NUM>. This pairing may be done in a number of ways.

The parameter determiner <NUM> determines <NUM> a plurality of tyre parameters that may be used by the alert generator <NUM> to determine whether an alert signal should be transmitted to the driver indicator unit <NUM>. The parameter determiner <NUM> may be configured to determine at least the following tyre parameters:.

The high/low and very high/low pressure parameters may collectively be termed pressure parameters. The leakage parameter and the blowout parameter may collectively be termed rate parameters.

The pressure sensor <NUM> senses <NUM> the tyre pressure at intervals, for example every <NUM> seconds. The alert generator <NUM> compares the sensed pressure with the determined tyre parameters and determines whether an alert signal should be transmitted based on the result of that comparison. It is noted that in order to assess the sensed pressure against the rate parameters, one or more previously sensed pressures must also be used. These may be stored in the memory <NUM>.

If the sensed pressure or rate of change of pressure is not outside one or more of the determined parameters then no alert is generated and the tyre pressure is sensed again by the pressure sensor <NUM> after the next interval period. If the alert generator <NUM> determines that the sensed pressure or rate of change of pressure are outside one or more of the tyre parameters then the alert generator <NUM> generates <NUM> an alert signal and the transmitter <NUM> transmits <NUM> the alert signal to the driver indicator unit <NUM>.

The driver indicator unit receives the alert signal and the display generator <NUM> controls the display <NUM> to display <NUM> the alert to the driver. It is noted again that the driver indicator unit <NUM> does not receive an absolute value for the tyre pressure. Further, the driver indicator unit <NUM> does not store any information on what the calibrated pressure is (i.e. the correct pressure for the tyre) or what any of the tyre parameters are. The driver indicator unit <NUM> merely receives an alert signal and makes a corresponding indication to the driver. This reduces considerably the power consumption of the driver indicator unit <NUM> as large LCD screens are not necessary and allows the use of a solar panel to provide electrical power rather than having to connect the driver indicator unit <NUM> to an internal vehicle power source. Therefore, the driver indicator unit may comprise a solar panel on an upper surface thereof. The upper surface of the driver indicator unit <NUM> may also comprise an adhesive or other securing means for retaining the sensing module against the windscreen of the vehicle. In exemplary methods and apparatus, the driver indicator unit <NUM> may require <NUM>/<NUM>th the electrical power of a typical unit in known systems.

In the case of a high/low pressure alert, the alert generator <NUM> generates the alert if the sensed pressure is greater than or less than the calibrated pressure by more than the percentages mentioned above (e.g. <NUM>%). The high/low pressure alert signal may be transmitted by the transmitter <NUM> to the driver indicator unit <NUM> every <NUM> seconds for <NUM> seconds. The pressure alert signal is transmitted immediately upon determining that the sensed pressure is high/low and is transmitted in multiple frames, ensuring that the risk of transmission loss is all but eliminated. This high rate of transmission and immediate pressure alert transmissions may be favourably compared to known TPMSs, which may transmit typically just a one or two frames of pressure value and sensor ID once every <NUM> minutes or so. Exemplary methods and apparatus ensure that the driver is alerted quickly and with a high confidence that the alert will be received by the driver indicator unit <NUM>.

Known after sale (or retro-fit) TPMSs typically display the actual tyre pressure as a key feature. This means that the sensing module needs to update the driver indicator unit continually. Consequently, to reduce the power consumption of this regular transmission, only one or two frames is typically transmitted every five minutes and the actual tyre pressure is displayed by the driver indicator unit. For high and low pressure the driver indicator unit computes whether to alert the driver or not. This continual sending and updating of actual tyre pressure by the sensing module is energy consuming and hence the battery life is greatly reduced. There is also a high risk of delay of the transmission of the alert signal due to the time gap of <NUM> minutes. More seriously, due to the relative lack of robustness of sending the alert signal in just one or two frames, a major concern is that an excess of <NUM> or <NUM> minutes may pass before the receiver of the driver indicator unit adequately receives the data necessary to signal an alert to the driver to take evasive action.

Therefore, in exemplary arrangements disclosed herein, the sensing module <NUM> transmits the alert signal only when the sensed pressure is determined to be not aligned with one of the tyre pressure parameters, for example when the sensed pressure is determined to be high or low. When the sensed pressure is aligned with the tyre pressure parameters, the sensing module <NUM> may be configured not to transmit any data indicating what the sensed pressure is to the driver indicator unit <NUM>.

In conclusion, the further merits of allowing the sensing module <NUM> to compute the alert signal, combined with the realisation that displaying the actual tyre pressure at the driver indicator unit <NUM> is unnecessary, results in a more responsive, multiple-frame and concentrated alert signal which greatly improves the overall system safety.

In the case of a very high/low pressure alert, the alert generator <NUM> generates the alert if the sensed pressure is greater than or less than the calibrated pressure by more than the percentages mentioned above (e.g. <NUM>%). The very high/low pressure alert signal may be transmitted by the transmitter <NUM> to the driver indicator unit <NUM> every <NUM> seconds continuously for the remainder of the journey.

In the case of a leakage alert, the alert generator <NUM> generates the alert if the rate of change of the sensed pressure is greater than a specific percentage (e.g. <NUM>%) of the calibrated pressure within a specific period of time (e.g. one minute). The leakage alert signal may be transmitted by the transmitter <NUM> to the driver indicator unit <NUM> every <NUM> seconds continuously until the problem is resolved, for example by removal of the sensing module 104a-f from the tyre in question.

In the case of a blowout alert, the alert generator <NUM> generates the alert if the rate of change of the sensed pressure is greater than a rate associated with a drop from calibrated pressure to substantially atmospheric pressure within a specific period of time (e.g. <NUM> seconds). The blowout alert signal may be transmitted by the transmitter <NUM> to the driver indicator unit <NUM> every <NUM> seconds continuously until one of the following conditions occurs:.

In addition to the transmitted alert signal, the LED <NUM> may also illuminate <NUM> to indicate the sensing module 104a-f that has generated the alert signal. In exemplary arrangements, the colour and/or pattern (e.g. flashing rate) of the LED <NUM> may indicate the type of alert generated by the alert generator <NUM> of the sensing module 104a-f.

In exemplary arrangements, the sensing module 104a-f includes a motion sensor <NUM>, such as an accelerometer. The motion sensor <NUM> may be configured to detect when the vehicle <NUM> has stopped, for example if there is no detected motion for a specific period of time, such as <NUM> seconds or more. If the alert generator has generated an alert during the journey (i.e. before the motion sensor <NUM> detects that the journey has ended) then the LED <NUM> may be configured to illuminate when the motion sensor <NUM> detects that the vehicle <NUM> has stopped. In exemplary arrangements, the LED <NUM> may flash every <NUM> seconds for <NUM> minutes. The illumination of the LED <NUM> may end when the motion sensor <NUM> detects that the vehicle <NUM> has started moving again. The LED may be configured to illuminate for a maximum number of vehicle stops, e.g. <NUM>, in the same journey. If the sensing module 104a-f is not removed during the maximum number of stops then the LED <NUM> ceases to illuminate when the vehicle <NUM> stops in order to preserve battery life.

The motion sensor <NUM> may also detect the end of the journey by detecting no vehicle motion for at least a journey end period, e.g. <NUM> minutes. Movement after no vehicle motion for at least the journey end period signifies the start of a new journey. If a new journey starts and the tyre error is still the same for the sensing module 104a-f, then the LED <NUM> will repeat the above procedure for the maximum number of vehicle stops.

It is noted that journey end results in the tyre sensing module going into sleep mode. In sleep mode the tyre sensing module just has continual sensor monitoring of tyre pressure, NFC (Near Field Communication) and acceleration (needed to detect movement for wake up). Other systems, even when the vehicle is stationary, typically send actual tyre pressure data every five minutes continuously resulting in excessive and unnecessary battery drain.

The sensing module may also comprise a temperature sensor <NUM> configured to detect the temperature of the gas retained within the tyre. Accordingly, the parameter determiner <NUM> may be further configured to determine a temperature parameter or a temperature parameter may be programmed into the sensing module 104a-f during manufacture. The temperature parameter is a temperature threshold above which the alert generator <NUM> will generate a temperature alert. In exemplary arrangements, the temperature threshold may be in a range from <NUM> degrees to <NUM> degrees and may specifically be <NUM> degrees. If the sensed temperature exceeds the threshold temperature then the alert generator <NUM> generates the temperature alert signal and the transmitter <NUM> transmits the temperature alert signal to the driver indicator unit <NUM>. The transmitter <NUM> may transmit the temperature alert signal once every <NUM> seconds for <NUM> seconds or until the temperature drops below the threshold temperature.

In specific arrangements, the sensing module may be part of a retro-fit (or after sales) TPMS.

<FIG> shows an exemplary alert signal data packet <NUM> comprising <NUM> bytes of data (bytes <NUM>-<NUM>). Byte <NUM> is shown as comprising status information, which in the exemplary arrangement of <FIG> is information relating to the sensor and/or the sensed pressure of the gas inside the pneumatic tyre. Byte <NUM> is expanded below the alert signal data packet <NUM> to show the data conveyed by each bit. The data relating to each bit of byte <NUM> is identified below.

In exemplary arrangements, the TPMS of <FIG> may further comprise a pressure reader module or user module <NUM>. However, it is noted that the pressure reader module or user module <NUM> may be used with tyre pressure sensing modules from any TPMS system and not just the system described above. The embodiments described below relating to confirmation of walk-around and/or pressure checks may therefore be construed broadly to apply to any TPMS that comprises one or more wheel based tyre pressure sensing modules in communication with an apparatus, such as a driver indicator unit.

The following description relates to one embodiment in which the user module comprises a pressure reader module. In further arrangements, the user module may comprise a mobile phone, and the below description may also apply to such arrangements. As explained in more detail below, a user of the system may walk around the vehicle <NUM> with the pressure reader module <NUM>. The user may hold the reader module <NUM> in close proximity to one or more of the tyre pressure sensing modules 104a-f in turn. When the reader module <NUM> is in close proximity to the sensing modules 104a-f, it may transmit a signal that activates one or more components of a sensing module 104a-f. The signal may form part of a request for tyre pressure data. The sensing module 104a-f receives the request at the receiver <NUM> and then determines the pressure of the air in the tyre of the wheel 106a-f, and optionally transmits it to the pressure reader module <NUM>. In other arrangements, the sensing module 104a-f may display the tyre pressure. The activated components may then switch off again. In some exemplary arrangements, the pressure reader module <NUM> receives data transmitted by the sensing module 104a-f and displays the tyre pressure on a display. The data may comprise one or more of: the value of the sensed pressure, a time stamp indicating the time that the sensing module received the signal from the pressure reader module to activate the one or more components of the sensing module, a time stamp indicating the time that the sensing module transmitted the determined pressure to the pressure reader module. In further exemplary arrangements, the pressure reader module <NUM> may receive the data transmitted by the sensing module and transmit the data to a further apparatus. Alternatively, the sensing modules 104a-f may be configured to transmit the data to the further apparatus upon activation by the pressure reader module <NUM>.

<FIG> shows a flow diagram of a method for confirming a tyre pressure check has been carried out on a single sensing module 104a-f.

The sensing module 104a-f is in "journey end" mode <NUM>. This mode may be construed broadly to mean that the sensing module 104a-f is awaiting the start of a new journey. In some arrangements, the journey end mode of the sensing module 104a-f may encompass a sleep mode that is initiated a certain period of time after the motion sensor <NUM> stops detecting motion.

In the journey end mode <NUM>, the pressure check register <NUM> indicates that the pressure reader module <NUM> has not been used. The pressure check register <NUM> may be cleared when the sensing module 104a-f is in journey end mode, such that it indicates no usage of the pressure reader module <NUM>.

The sensing module 104a-f determines whether a request for tyre pressure data has been received <NUM> by the receiver <NUM>. If so, the pressure check register <NUM> is updated <NUM>.

The pressure check register <NUM> is polled <NUM> and it is determined <NUM> whether the pressure check register <NUM> indicates that a request for tyre pressure data has been received. Updating the pressure check register <NUM> comprises storing data indicating that a request for tyre pressure data has been received from the pressure reader module <NUM>. The pressure reader module <NUM> is configured to transmit a request for tyre pressure data to the sensing module 104a-f when it is used. The request is received by the receiver <NUM>. The pressure check register <NUM> stores data indicating that such a request has been received. This may be an indication that the pressure reader <NUM> has been used on that sensing module 104a-f. Therefore, each time the pressure check register <NUM> is polled, if data indicating that a request for tyre pressure data has been received then it can be inferred that the pressure reader module has been used and the tyre pressure check has been carried out.

The pressure check register <NUM> may be polled <NUM> at regular (or irregular) intervals to determine whether the pressure reader <NUM> has been used. Alternatively, the pressure check register <NUM> may be read based on an event, such as the updating of the pressure check register <NUM>. In such arrangements, steps <NUM> and/or <NUM> may be begun after step <NUM>.

If after polling the pressure check register <NUM> indicates <NUM> that no request for tyre pressure data has been received, the motion sensor <NUM> determines whether the wheel to which the sensing module 104a-f is fitted has begun to rotate and/or is rotating <NUM>.

If the motion sensor <NUM> determines that the wheel has not begun to rotate and/or is not rotating then the pressure check register <NUM> is polled again <NUM>. If the motion sensor <NUM> determines that the wheel has begun to rotate and/or is rotating then the transmitter <NUM> transmits <NUM> a negative indication to the further apparatus, which may be a driver indicator unit <NUM>. The negative indication specifies that the tyre pressure was not checked before the journey of the vehicle began.

If after polling the pressure check register <NUM> indicates <NUM> that a request for tyre pressure data has been received, the motion sensor <NUM> determines whether the wheel to which the sensing module 104a-f is fitted has begun to rotate and/or is rotating <NUM>.

If the motion sensor <NUM> determines that the wheel has not begun to rotate and/or is not rotating then the sensing module 104a-f waits until rotation of the wheel is detected. It may be unnecessary to poll the pressure check register <NUM> again once it has been updated. If the motion sensor <NUM> determines that the wheel has begun to rotate and/or is rotating then the transmitter <NUM> transmits <NUM> a positive indication to the further apparatus. The positive indication specifies that the tyre pressure was checked before the journey of the vehicle began.

The above process may be repeated on a plurality of sensing modules 104a-f fitted to the vehicle <NUM>. In some arrangements, sensing modules 104a-f may be fitted to all wheels.

The further apparatus, which may be the driver indicator unit <NUM> may be configured to receive at the receiver <NUM> the positive and/or negative indications from the sensing modules 104a-f. Based on the received indications, the pressure check confirmer <NUM> is configured to determine whether a vehicle tyre pressure check has been carried out. A vehicle tyre pressure check may be considered to have been carried out when a plurality of individual tyre pressure checks have been carried out, and therefore when a plurality of positive indications have been received.

The plurality of positive indications may include positive indications from all sensing modules 104a-f fitted to the vehicle <NUM>. Alternatively, the plurality of positive indications may include positive indications from selected sensing modules, such as at least one sensing module at each corner of the vehicle <NUM>, at least one sensing module at the front and/or rear of the vehicle <NUM>, at least two sensing modules, or at least percentage of the sensing modules fitted to the vehicle <NUM>, say at least <NUM>%, at least <NUM>% or at least <NUM>%. This may be sufficient to indicate that a walk-around check has been carried out.

The driver indicator unit <NUM> may display an indication to a driver of the vehicle <NUM> whether a walk-around check or vehicle tyre pressure check has been carried out. This may comprise a warning, which may be visual and/or audible. In some exemplary arrangements, the driver indicator unit <NUM> may transmit the indication of whether the vehicle tyre pressure check and/or the walk-around check has been conducted to a central server. The central server may therefore comprise data specifying a log of vehicle tyre pressure checks and/or walk-around checks for the vehicle <NUM>. This data may be accessed by a user to monitor vehicle checks and may be cross referenced with journey data.

The above arrangements provide methods and apparatus for having greater confidence that a vehicle tyre pressure check and/or walk-around check has been carried out. Non-conformance to such checks is a major issue for fleet vehicle operators and has direct implications for vehicle maintenance and safety.

In some arrangements, the further apparatus (e.g. the driver indicator unit <NUM>) may be configured to immobilise the engine, motor or other drivetrain of the vehicle <NUM> in dependence on the receipt of the plurality of indications from the sensing modules 104a-f. That is, if positive indications are not received from the plurality (which may or may not be all) of the sensing modules 104a-f then the driver may be prevented from beginning a journey.

In an arrangement, the pressure reader module <NUM> may be configured to receive data from the tyre pressure sensing module 104a-f after a pressure check has been initiated. In such arrangements, the pressure reader module <NUM> may comprise a pressure check register to store an indication that the pressure check has taken place. The pressure reader module <NUM> may comprise a transmitter to transmit data stored in the pressure check register to a server located within a telecommunications network. This may be done via a network connected device, such as a user equipment, e.g. a mobile phone or similar, which is configured to receive the data and upload it to the server. The server and/or the pressure reader module <NUM> may also comprise a pressure check confirmer configured in a similar fashion to that described elsewhere herein.

In other exemplary arrangements, a user module <NUM>, which need not be a pressure reader module, may be configured to transmit data to a tyre pressure sensing module 104a-f indicating that it is within a range of the tyre pressure sending module 104a-f. The range may be any of less than <NUM> away from the tyre pressure sensor, less than <NUM> away from the tyre pressure sensor, less than <NUM> away from the tyre pressure sensor, less than <NUM> away from the tyre pressure sensor or less than <NUM> away from the tyre pressure sensor.

In such arrangements, the transmitter <NUM> of the tyre pressure sensing module 104a-f may be configured to transmit tyre pressure data that is indicative of the tyre pressure to an apparatus and optionally not to the user module <NUM>. The apparatus may be a driver indicator unit <NUM> or a user equipment, such as a mobile phone or other device.

In each case, there is no explicit need for the user module <NUM> to conduct a pressure check per se. This may be because the tyre pressure sensing module 104a-f is capable of transmitting that data directly to the apparatus (e.g. driver indicator unit <NUM>). However, the fact that a user module <NUM> has been within range of one or more tyre pressure sensor modules 104a-f may be used as an indication that the user was also at that location and therefore be a proxy for indicating that a walk-around check has been undertaken.

The driver indicator unit <NUM> or user equipment may receive data from one or more tyre pressure sensing modules 104a-f indicating that the user module <NUM> has been within range. The walk-around check confirmer <NUM> stores data indicating that the user module <NUM> has been within range and may be configured to confirm whether a walk-around has been undertaken based on the data received from the tyre pressure sensing modules 104a-f. The transmitter <NUM> may be configured to upload data indicating whether a walk-around has been undertaken to a server.

The user module or pressure reader module <NUM> may communicate with the tyre pressure sensing module using NFC or similar and may communicate with the user equipment using Bluetooth (RTM) or similar, for example. This may particularly be the case in arrangements where the apparatus comprises a user equipment. The user equipment may be configured to upload data indicating whether a walk-around has been undertaken to a server.

A computer program may be configured to provide any of the above described methods. The computer program may be provided on a computer readable medium. The computer program may be a computer program product. The product may comprise a non-transitory computer usable storage medium. The computer program product may have computer-readable program code embodied in the medium configured to perform the method. The computer program product may be configured to cause at least one processor to perform some or all of the method.

Various methods and apparatus are described herein with reference to block diagrams or flowchart illustrations of computer-implemented methods, apparatus (systems and/or devices) and/or computer program products.

Computer program instructions may also be stored in a computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instructions which implement the functions/acts specified in the block diagrams and/or flowchart block or blocks.

A tangible, non-transitory computer-readable medium may include an electronic, magnetic, optical, electromagnetic, or semiconductor data storage system, apparatus, or device. More specific examples of the computer-readable medium would include the following: a portable computer diskette, a random access memory (RAM) circuit, a read-only memory (ROM) circuit, an erasable programmable read-only memory (EPROM or Flash memory) circuit, a portable compact disc read-only memory (CD-ROM), and a portable digital video disc read-only memory (DVD/Blu-ray).

The computer program instructions may also be loaded onto a computer and/or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer and/or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the block diagrams and/or flowchart block or blocks.

Accordingly, the invention may be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.) that runs on a processor, which may collectively be referred to as "circuitry," "a module" or variants thereof.

Finally, other blocks may be added/inserted between the blocks that are illustrated.

Claim 1:
A tyre pressure sensing module (<NUM>, <NUM>) for fitting to a wheel (<NUM>) of a vehicle (<NUM>) comprising a pneumatic tyre, the sensing module (<NUM>, <NUM>) comprising:
a pressure sensor (<NUM>) for sensing a pressure of a gas retained within the pneumatic tyre and comprising a pressure check register (<NUM>) configured to store data indicating that a request for tyre pressure data has been received;
a receiver (<NUM>) configured to receive, from a pressure reader module of a user module (<NUM>), data comprising the request for tyre pressure data indicative of the pressure of the gas retained within the pneumatic tyre and indicating that the user module (<NUM>) is proximal to the tyre pressure sensor (<NUM>);
a transmitter (<NUM>) configured to transmit to an apparatus, data comprising an indication confirming whether a tyre pressure check has been carried out based on whether the request for tyre pressure data was received, wherein receipt of the request for tyre pressure data indicates that the user module (<NUM>) has been proximal to the tyre pressure sensor (<NUM>).