Patent Description:
In general, technologies for facilitating driving convenience and ensuring vehicle driver safety include vehicular radar, tire air pressure detection devices, remote ignition devices, and geographical information systems.

Meanwhile, among the numerous components of a vehicle, tires are the components which are in direct contact with the road, and thus the tires perform functions such as bearing the weight of the vehicle, delivering the driving force and braking force to the ground and cushioning against impacts from the road surface, and therefore the state of the tires relates directly to the safety of the driver. For this reason, it is necessary to continuously monitor the state of the tires during travel. For example, tire air pressure detection devices measure the pressure and temperature of the tires from sensors installed in the wheels, and notify the user of the pressure and temperature, and thus can prevent the occurrence of defects in the tires in advance.

One such safety apparatus installed in vehicles to prevent such defects in the tires is a tire pressure monitoring system (TPMS). Such tire pressure monitoring systems (TPMS) are systems that give a warning when the tire pressure falls below a reference pressure, by means of a tire module unit (wheel unit, WU), that has been installed in the tire, monitoring the pressure of the tire so as to periodically transmit tire pressure information wirelessly (via a radio frequency (RF)) to an electronic control unit (ECU) inside the vehicle.

But RF (radio frequency) data transceiving methods like the one above involve wireless communication via RF at <NUM> between the TPMS WU and the electronic control unit (ECU), so problems of the electronic control unit (ECU) being unable to receive the RF signal may occur due to effects such as reflection and fading of the transmitted signal.

Meanwhile, as an additional function of tire pressure monitoring systems (TPMS), there is a function of learning the positions of the tires so as to notify the user of the position of any tire at which low pressure has occurred, and there are two types of method for learning the positions of tires in the prior art.

Firstly, the LF initiator (LFi) method is a method in which low frequency initiators (LFi) are installed in four places in tire adjacent spaces inside the vehicle, an electronic control unit (ECU) controls the LFi to sequentially transmit LF signals toward wheel units (WU) which are installed on each of the wheels (i.e. each of the tires), and then, when each wheel unit (WU) installed on each of the wheels receives the LF signal, the changed tire state is transmitted to the electronic control unit (ECU) using an RF signal, and thus the electronic control unit (ECU) matches the RF received state to the wheel unit (WU) ID thereby learning the tire position. But in this method, since four LFi must be additionally installed on the vehicle, there are the problems of costs increasing and wiring becoming complicated, as well as leading to deterioration in fuel efficiency due to the increase in the weight of the vehicle.

Secondly, in the Loc on Sync method, each wheel unit (WU) installed on each tire transmits an RF signal only at a specific phase (i.e. a specific tire angle), and then, the electronic control unit (ECU) confirms the phase (i.e. angle of each tire) information for each wheel from wheel speed sensors by communicating with other modules. This is to say, the electronic control unit (ECU) learns the tire position by determining the position with the highest correlation among the phases of each wheel every time a wheel unit (WU) signal for each of the four wheels is collected. But this method has a problem in that, when the vehicle is travelling at a speed of <NUM>/h or more, tire position learning mistakes can occur due to specific phase (i.e. tire angle) position measurement errors of the TPMS WU.

Consequently, the situation is such that technology for improving upon the problems of conventional RF and tire position learning techniques is needed.

Background art of the present invention is disclosed in <CIT> (Registered <NUM> February <NUM>, TIRE MONITORING DEVICE AND VEHICLE COMPRISING THE SAME), <CIT> and <CIT>.

According to one aspect of the present invention, the present invention was created in order to resolve problems such as those described above, and specifically the object of the present invention is to provide a tire position learning apparatus and method for a tire pressure monitoring system (TPMS), which allow the tire position in the tire pressure monitoring system to be learned by using ultra-wide band (UWB) technology.

The tire position learning apparatus for a tire pressure monitoring system according to one aspect of the present invention is a tire position learning apparatus for a tire pressure monitoring system, characterized by comprising: a plurality of tire module units mounted on a tire of the vehicle respectively so as to detect pressure information and transmit same via an ultra-wide band (UWB) signal; and a vehicle module unit operable to communicate with the plurality of tire module units via UWB signals so as to detect the individual tire pressures and any tire in a position where low pressure has occurred and notifies the user of same.

The present invention is characterized in that the vehicle module unit comprises: a plurality of vehicle UWB communication units operable to respectively communicate with the plurality of tire module units via UWB signals.

The present invention is characterized in that each of the plurality of vehicle UWB communication units is respectively mounted in a designated position on the exterior of the vehicle.

The present invention is characterized in that the vehicle module unit comprises: a control unit operable to calculate and learn the position of each tire by using distance information measured in a plurality of the vehicle UWB communication units, by using UWB signals respectively transmitted from a plurality of the tire module units, and the distance information is information about the distance from the plurality of vehicle UWB communication units to a plurality of the tire module units.

The present invention is characterized in that the vehicle module unit comprises: a display unit operable to display position and pressure information for each tire as calculated and learned in the control unit, and the display unit includes a vehicle dashboard.

The present invention is characterized in that the control unit is operable to learn the positions of the tires by using trigonometry on the basis of the information about the distances from respective vehicle UWB communication units to a plurality of the tire module units, and, in order to use trigonometry, the control unit is operable to use distance information with respect to one tire module unit, as detected in at least three vehicle UWB communication units.

The present invention is characterized in that the tire module unit comprises: a sensor unit operable to detect the pressure of the tire; and a tire UWB communication unit operable to wirelessly output tire pressure information, that has been detected by means of the sensor unit, using a UWB signal.

The tire position learning method for a tire pressure monitoring system according to another aspect of the present invention is a tire position learning method for a tire pressure monitoring system, characterized by comprising: a step in which a plurality of tire module units, each of which is respectively mounted on a tire of the vehicle, detects pressure information for each tire and transmits same via an ultra-wide band (UWB) signal; and a step in which a vehicle module unit communicates with the plurality of tire module units via UWB signals so as to detect the individual tire pressures and any tire in a position where low pressure has occurred and notifies the user of same.

The present invention is characterized in that, in order to communicate with the plurality of tire module units via UWB signals, the vehicle module unit comprises a plurality of vehicle UWB communication units each of which respectively communicates with the plurality of tire module units via UWB signals.

The present invention is characterized in that, in order to detect the positions of the tires, in the vehicle module unit, the control unit calculates and learns the position of each tire on the basis of distance information measured in a plurality of the vehicle UWB communication units, by using the UWB signals respectively transmitted from the plurality of tire module units, and the distance information is information about the distance from the plurality of vehicle UWB communication units to a plurality of the tire module units.

The present invention is characterized in that, in order to detect the positions of the tires and notify the user of same, the vehicle module unit comprises: a display unit which displays position and pressure information for each tire as calculated and learned in the control unit, and the display unit includes a vehicle dashboard.

The present invention is characterized in that, in order to calculate and learn the position of each tire, the control unit learns the positions of the tires by using trigonometry on the basis of the information about the distances from respective vehicle UWB communication units to a plurality of the tire module units, and, in order to use trigonometry, the control unit uses distance information with respect to one tire module unit, as detected in at least three vehicle UWB communication units.

The present invention is characterized in that, in the step in which the plurality of tire module units detects pressure information for each tire and communicates same via ultra-wide band (UWB) signals, sensor units of the tire module units detect the pressures of the tires and the UWB communication units of the tire module units wirelessly output the tire pressure information, that has been detected by means of the sensor units, using UWB signals.

According to one aspect of the present invention, the present invention specifically allows the tire position in a tire pressure monitoring system (TPMS) to be learned by using ultra-wide band (UWB) technology.

Hereinafter, an embodiment of the tire position learning apparatus and method for a tire pressure monitoring system according to the present invention will be described with reference to the accompanying drawings.

In this process, the thickness of lines or the size of the components shown in the drawings may be exaggerated for clarity of the description and convenience. In addition, the terms used in the following text are defined in relation to their functions in the present invention, and can vary depending on the intention of the user or operator, or on customary practice. Thus, definitions of such terms should be made based on the content throughout the entirety of this specification.

<FIG> is an illustrative drawing showing a schematic configuration of the tire position learning apparatus for a tire pressure monitoring system according to one embodiment of the present invention, and <FIG> is an illustrative drawing for explaining the mounting positions of the plurality of vehicle UWB communication units (111a-111d) in <FIG>.

As shown in <FIG>, the tire position learning apparatus for a tire pressure monitoring system according to the present embodiment comprises: a vehicle module unit (<NUM>); and a plurality of tire module units (<NUM>, <NUM>, <NUM>, <NUM>).

The vehicle module unit (<NUM>) comprises: a plurality of vehicle ultra-wide band (UWB) communication units (111a-111d); a control unit (<NUM>); and a display unit (<NUM>).

Each of the plurality of tire module units (<NUM>-<NUM>) comprises: a tire UWB communication unit (<NUM>); and a sensor unit (<NUM>).

Each of the plurality of vehicle ultra-wide band (UWB) communication units (111a-111d) is mounted at a designated position on the exterior of the vehicle (e.g. the wheel lateral edge portion of the vehicle exterior) (see <FIG>).

The plurality of vehicle ultra-wide band (UWB) communication units (111a-111d) can receive ultra-wide band (UWB) signals transmitted from the plurality of (at least three) tire module units (<NUM>-<NUM>) so as to measure distance (i.e. the distances from each vehicle UWB communication unit to a plurality of the tire module units) (see <FIG>).

<FIG> is an illustrative drawing for explaining the method for measuring the distance from the plurality of vehicle UWB communication units (111a-111d) to each of the tire module units (<NUM>-<NUM>) in <FIG>.

Here, the time of flight (ToF, flight-time distance measurement) method can be used in order to accurately measure distance, in that the distances from the plurality of vehicle UWB communication units (111a-111d) to each tire module unit (<NUM>-<NUM>) change in real-time in accordance with the rotation of the tires during vehicle travel, and consequently the control unit (<NUM>) can calculate and learn the positions of the tires on the basis of the distance information (i.e. the distances from the vehicle UWB communication units to each tire module unit).

It should be noted that, the UWB technology is technology which has evolved from existing local area wireless technology such as Wi-Fi, Bluetooth, and GPS, and has the characteristic of being able to process situational information such as the UWB anchor position, anchor movement, and the distance to other equipment to an accuracy of a number of centimeters, which has been difficult in the prior art.

The control unit (<NUM>) calculates and learns the position of each tire by using information about distance(i.e. the distances from each vehicle UWB communication unit to the plurality of tire module units) measured by the plurality of vehicle UWB communication units (111a-111d) each receiving the UWB signals transmitted from the plurality of tire module units (<NUM>-<NUM>).

The display unit (<NUM>) displays position and pressure information for each tire as calculated and learned in the control unit (<NUM>). For example, the display unit (<NUM>) can display the position information of the tire by utilizing the vehicle dashboard.

The tire UWB communication units (<NUM>) wirelessly output the tire pressure information, that has been detected by means of the sensor unit (<NUM>), using UWB signals.

The sensor unit (<NUM>) comprises a sensor which detects the pressure of the tire.

Here, the sensor unit (<NUM>) is implemented so as to be able to perform the function of a control unit, and the plurality of tire module units (<NUM>-<NUM>) may also be each provided with additional control units (not shown).

<FIG> is a flowchart for explaining the tire position learning method for a tire pressure monitoring system according to one embodiment of the present invention.

With reference to <FIG>, the control unit (<NUM>) of the vehicle module unit (<NUM>) starts (S101) tire position learning during vehicle travel, and directs (S102) tire position learning requests to the vehicle UWB communication unit (<NUM>) depending on the designated vehicle communication method (e.g. CAN, LIN).

Consequently, the vehicle UWB communication unit (<NUM>) repeats (S103) the request for position-related information and response by using the tire UWB communication unit (<NUM>) and a UWB signal.

For example, the plurality of vehicle UWB communication units (111a-111d) receives UWB signals transmitted from the plurality of (at least three) tire module units (<NUM>-<NUM>) and thereby measure the distances therefrom (i.e. the distances from each vehicle UWB communication unit to a plurality of the tire module units). Here, the distances from the plurality of vehicle UWB communication units (111a-111d) to each tire module unit (<NUM>-<NUM>) change in real-time in accordance with the rotation of the tires during vehicle travel.

Consequently, the vehicle UWB communication unit (<NUM>) delivers (S104) information about the distances to each tire module unit (<NUM>-<NUM>), to the control unit (<NUM>) of the vehicle module unit (<NUM>) in accordance with the designated vehicle communication method (e.g. CAN, LIN).

Consequently, as shown in <FIG>, the control unit (<NUM>) calculates and learns (S105) the positions of the tires on the basis of the information about distance (i.e. the distances from the vehicle UWB communication units to each tire module unit).

It should be noted that, in the method for measuring distance using ultra-wide band (UWB) signals, there is little effect with regard to signals received via a multipath as the method uses a designated wireless band and impulse response (IR). With wireless signals that pass via any usual multipath, the signal strength changes in an irregular manner due to reflection off the surroundings when signals overlap at a single time point as the phase changes, or there is attenuation, but, in the case of ultra-wide band signals, the effects caused by a multipath on change of phase and strength are small and so it is possible to stably measure the signal strength. Consequently, the present embodiment makes it possible to accurately find the position of the tire through trigonometry by using the stable signal strength dependent on the distance.

When learning the positions of the tires as described above is completed, learning is finished (S106).

As described above, the present embodiment has the advantageous effect of allowing the tire position in a tire pressure monitoring system (TPMS) to be learned by using ultra-wide band (UWB) technology.

Claim 1:
A tire position learning apparatus for a tire pressure monitoring system comprising:
a plurality of tire module units(<NUM>- <NUM>) mounted on a tire of the vehicle respectively so as to detect pressure information and transmit same via an ultra-wide band (UWB) signal; and
a vehicle module unit (<NUM>) operable to communicate with the plurality of tire module units (<NUM>- <NUM>) via UWB signals so as to detect individual tire pressures and any tire in a position where low pressure has occurred and notifies the user of same, characterized in that the vehicle module unit (<NUM>) comprises: a plurality of vehicle UWB communication units (<NUM>) operable to respectively communicate with the plurality of tire module units (<NUM>- <NUM>) via UWB signals.