Patent Publication Number: US-2006015286-A1

Title: Tire pressure measure system and method using ultra wideband technology

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a tire pressure measure system and method using the ultra wideband (UWB) technology and, more particularly, to a tire pressure measure system and method making use of the UWB wireless transmission technique for data transmission.  
      2. Description of Related Art  
      Blowouts may occur while driving a vehicle, accounting for 6% of highway accidents. Reasons causing blowout are attribute mostly to the tire pressure. A tire is easily affected by external forces or weather variations to wear and deform during driving, hence affecting the tire pressure and driving safety. Besides, when a tire is not sufficiently inflated, the pressure variation in the tire will be influenced. A driver not maintaining tires properly or checking tires on time using a tire pressure gauge may have a blowout while driving. Further, the other hand, keeping a normal tire pressure can reduce fuel consumption. Therefore, the measurement of a vehicle tire pressure is very important for driving safety.  
      The ultra wideband (UWB) technology is a short-distance wireless communications technology developed by the U.S. military. Compared to other short-distance communications standards, the data rate of the 802.11b standard is only 5/1000 of that of the UWB technology. The first generation UWB technology has a transmission speed of 100 MB/s, and the second generation UWB technology has a transmission speed as high as 400 MB/s. The UWB technology has also the characteristics of immunity to interference, accurate positioning, and high data transmission safety.  
      Accordingly, the present invention proposes a data transmission technique using the UWB technology to measure the tire pressure in a wireless way. The tire pressure can thus be monitored at any time for vehicle maintenance without using a conventional tire pressure gauge. Hazards due to tire pressure problems while driving can thus be avoided.  
     SUMMARY OF THE INVENTION  
      An object of the present invention is to provide a tire pressure measurement system and method making use of the UWB wireless transmission technique in a local environment of a vehicle to measure the tire pressure of a vehicle.  
      The present invention has at least a data fetch terminal disposed on a tire aircock to get a tire pressure signal. A user can use a remote host control terminal to send an inquiry signal to these data fetch terminals by means of the UWB technology, thereby awaking these data fetch terminals from the sleep mode to fetch the tire pressure signal. When the data fetch terminals receives the inquiry signal sent from the remote host control terminal by means of the UWB technology, the tire pressure signal is also fetched. After the tire pressure signal is processed by the data fetch terminals, the data fetch terminals send a reply signal to the remote host control terminal by means of the UWB technology. After the host control terminal receives and processes the reply signal, the tire pressure signal obtained by the data fetch terminals is displayed on a display unit so that the user can clearly know the tire pressure of a vehicle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings, in which:  
       FIG. 1  is a an operation environment diagram of a tire pressure measure system of the present invention;  
       FIG. 2  is a circuit block diagram of a data fetch terminal of a tire pressure measure system of the present invention;  
       FIG. 3  is a circuit block diagram of a host control terminal of a tire pressure measure system of the present invention; and  
       FIG. 4  is a flowchart of a tire pressure measure method of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      As shown in  FIG. 1 , the present invention provides a tire pressure measure system and method making use of the UWB wireless transmission technique in a local environment of a vehicle to measure the tire pressure of a vehicle. The tire pressure measure system comprises at least a data fetch terminal and a host control terminal. The data fetch terminals  1  are disposed on tire aircocks of a wheeled vehicle to fetch tire pressure signals of the tires and perform signal conversion. Moreover, a user  4  can operate the host control terminal  2  to get and display the tire pressure signals by means of the UWB wireless transmission technique so that he can clearly know the tire pressure values of the tires.  
      As shown in  FIG. 2 , the data fetch terminal  1  comprises a pressure message fetch unit  10 , an analog/digital conversion unit  12 , a data processing unit  14 , a first UWB communications module  16  and a first antenna  18 .  
      Reference is made to  FIG. 2  as well as  FIG. 1 . The data fetch terminal  1  is connected to the tire aircock  5  via the pressure message fetch unit  10  to get a tire pressure signal, which is an analog signal. The analog/digital conversion unit  12  is connected to the pressure message fetch unit  10 , and is used to receive and convert the analog tire pressure signal into a digital tire pressure signal for output. The data processing unit  14  is connected to the analog/digital conversion unit  14 , and is used to receive and process the digital tire pressure signal. The first UWB communications module  16  is connected to the data processing unit  14 , and is used to receive the digital tire pressure signal processed by the data processing unit  14  and then send the same to a remote host terminal  2  via the first antenna  18  in a wireless way. The above digital tire pressure signal is a reply signal.  
      As shown in  FIG. 3 , the host control terminal  2  comprises a second antenna  20 , a second UWB communications module  22 , a micro control unit  24 , a display unit  26 , a memory unit  27  and an operational unit  28 .  
      Reference is made to  FIG. 3  as well as  FIG. 1 . The user  4  uses the operational unit  28  of the host control terminal  2  to measure tire pressure. A control signal is sent to the micro control unit  24  connected to the operational unit  28 . The micro control unit  24  receives and processes the control signal. The processed control signal is then sent to the second UWB communications module  22  connected to the micro control unit  24 . Finally, the second UWB communications module  22  sends the control signal to a remote data fetch terminal  1  via the second antenna  20  connected to the second UWB communications module  22  in a wireless way. The above control signal is an inquiry signal.  
      Reference is made to  FIG. 3  again. The memory unit  27  is connected to the micro control unit  24 , and is used for storage of digital data (i.e., serial number data of the data fetch terminal  1 ). The display unit  26  is connected to the micro control unit  24 , and is used for display of the tire pressure value and an operation interface.  
      Reference is made to  FIG. 1  as well as  FIGS. 2 and 3 . When the user  4  hasn&#39;t measured the tire pressure yet, the data fetch terminal  1  disposed on the tire aircock  5  enters a sleep mode (i.e., a power-saving mode). At this time, the data processing unit  14  of the data fetch terminal  1  will stop working. Therefore, there is no reply signal for output from the first UWB communications module  16 .  
      When the user measures the tire pressure, he can use the operational unit  28  of the host control unit  2  to send a control signal to the micro control unit  24  for processing. The processed control signal is then sent to the second UWB communications module  22 , which sends the control signal to the remote data fetch terminals  1  via the second antenna  20  by means of the UWN wireless data transmission technique. The control signal is an inquiry signal. The inquiry signal activates in turn the originally sleeping data fetch terminals  1  to perform fetching of the tire pressure signal.  
      After the data fetch terminals  1  convert and process the tire pressure signals, the first UWB communications modules  16  are used to send the tire pressure signals (the reply signals) to the host control terminal  1  via the first antennas  18  by means of the UWB wireless data transmission technique. The host control terminal  2  receives the reply signals by means of the UWB wireless transmission technique. The reply signals are then processed by the micro control unit  24  and displayed on the display unit  26  so that the user can clearly know the tire pressure values.  
      Further, a signal lower limit and a signal upper limit can be set in advance on the data fetch terminal  1 . In the sleep mode, if the tire pressure signal got by the pressure message fetch unit  10  of the data fetch terminal  1  is high then the signal upper limit or lower than the signal lower limit, the tire pressure signal will be processed by the data processing unit  14 . The data fetch terminal  1  then automatically outputs an alarm signal, which will be wirelessly sent to the remote host terminal  2  to alarm the user  4 .  
       FIG. 4  is a flowchart of a tire pressure measure method of the present invention. The method comprises the following steps. First, at least a tire of a wheeled vehicle is inflated (Step S 100 ). A tire pressure meter is then used to measure a tire pressure signal of each of these tires (Step S  102 ). Next, at least a data fetch terminal is installed on aircocks of these tires (Step S 104 ). A host control terminal is used to set a serial number of each data fetch terminal and set the tire pressure value of each tire to be a set tire pressure value (Step S 106 ). The serial numbers and the set tire pressure values are stored in a memory unit (Step S 108 ). When measuring tire pressure, the host control terminal is used to send an inquiry signal to these data fetch terminals (Step S 110 ). The host control terminal receives in turn the tire pressure signals from these data fetch terminals (Step S 112 ). Subsequently, the tire pressure signals are processed by the host control terminal to become the set tire pressure values (Step S 114 ). Finally, these set tire pressure values are displayed on a display unit (Step S 116 ).  
      Before sending an inquiry signal to these data fetch terminals (Step S 110 ), these data fetch terminals will enter a sleep mode (i.e., a power-saving mode). After sending an inquiry signal to these data fetch terminals (Step S 110 ), these data fetch terminals are activated for fetching of the tire pressure signals.  
      Although the present invention has been described with reference to the preferred embodiments thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.