(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2004/0220738 A1
`(43) Pub. Date: NOV. 4, 2004
`
`Nissila
`
`US 20040220738A1
`
`(54) PORTABLE PERSONAL DATA PROCESSING
`DEVICE
`
`(52) US. Cl.
`
`.................................................................. 702/3
`
`(75)
`
`Inventor: Seppo Nissila, Oulu (FI)
`
`(57)
`
`ABSTRACT
`
`Correspondence Address:
`HOFFMANN & BARON, LLP
`6900 JERICHO TURNPIKE
`SYOSSET, NY 11791 (US)
`
`(73) Assignee: Polar Electro Oy.
`
`(21) Appl. N0.:
`
`10/818,696
`
`(22)
`
`Filed:
`
`Apr. 6, 2004
`
`(30)
`
`Foreign Application Priority Data
`
`Apr. 17, 2003
`
`(FI) ............................................. 20030597
`
`Publication Classification
`
`(51)
`
`Int. Cl.7 ................................................... G06F 169/00
`
`The invention relates to a portable personal data processing
`device, such as a wrist-worn measuring device, a heart rate
`monitor, a subscriber terminal of a radio system, or a sports
`watch. The device comprises a temperature sensor (120) for
`measuring the ambient temperature and a humidity sensor
`(122) for measuring the ambient humidity. Furthermore,
`dependence information, which defines temperature values
`of the dew points corresponding to the humidity values, is
`stored in the device. The control unit (100) is configured to
`monitor the change rate of the measured temperature, to
`determine, on the basis of the change rate, the moment at
`which the temperature reaches the temperature value of the
`dew point corresponding to the measured humidity 0n the
`basis of the dependence information, and to provide a
`forecast on fog appearance in relation to the moment
`employing the user interface (102).
`
`
`
`APPLE 1013
`
`APPLE 1013
`
`1
`
`

`

`Patent Application Publication Nov. 4, 2004
`
`US 2004/0220738 A1
`
`120
`
`122
`
`124
`
`
`FIG. 1
`
`
`2
`
`

`

`US 2004/0220738 A1
`
`Nov. 4, 2004
`
`PORTABLE PERSONAL DATA PROCESSING
`DEVICE
`
`DESCRIPTION OF EMBODIMENTS
`
`FIELD
`
`[0001] The invention relates to a portable personal data
`processing device. Such as device is, for example, a wrist-
`worn measuring device, a heart rate monitor, a subscriber
`terminal of a radio system, or a sports watch for use as an
`instrument
`in sports, hiking, sailing, mountain climbing
`and/or in snow sports.
`
`BACKGROUND
`
`devices/sports
`[0002] Various wrist-worn measuring
`watches are known in the art which may be provided with a
`barometer or a thermometer. In devices of this kind, the
`weather is predicted by monitoring the air pressure and by
`drawing conclusions from it.
`
`BRIEF DESCRIPTION
`
`[0003] The object of the invention is to provide an
`improved portable personal data processing device.
`
`[0004] According to an aspect of the invention, there is
`provided a portable personal data processing device com-
`prising a control unit for control-ling the device, a user
`interface coupled to the control unit for giving commands to
`the device and obtaining feedback on its operation, and a
`temperature sensor coupled to the control unit for measuring
`the ambient temperature. The device further comprises a
`humidity sensor coupled to the control unit for measuring
`the ambient humidity, and dependence information, which
`defines temperature values for the dew points corresponding
`to the humidity values,
`is stored in the device, and the
`control unit is configured to monitor the change rate of the
`measured temperature,
`to determine, on the basis of the
`change rate, the moment when the measured temperature
`reaches the temperature value of the dew point correspond-
`ing to the measured humidity on the basis of the dependence
`information, and to provide a forecast on fog appearance in
`relation to the moment employing the user interface.
`
`[0005] The device according to the invention provides
`several advantages. No portable personal data processing
`devices are known that could predict appearance of fog. The
`user receives information on fog appearance, and thus he can
`be prepare himself for it. The information on fog may have
`an effect on route selection or travel plans, for example. In
`some applications, for example in mountain climbing or
`hiking, the device may help to avoid potential dangerous
`situations, such as falling or getting lost.
`
`LIST OF FIGURES
`
`[0006] The invention will now be described in greater
`detail by means of preferred embodiments with reference to
`the accompanying drawings, in which
`
`[0007] FIG. 1 is a simplified block diagram illustrating
`components of a portable personal data processing device;
`
`[0008]
`
`FIG. 2 illustrates a wrist-worn measuring device;
`
`[0009] FIG. 3 illustrates a subscriber terminal of a radio
`system; and
`
`[0010]
`
`FIG. 4 illustrates prediction of fog appearance.
`
`[0011] Referring to FIG. 1, the structure of a portable
`personal data processing device will de described in an
`appropriately simplified manner. The device comprises a
`control unit 100 for controlling the device, and a user
`interface 102 coupled to the control unit 100 for giving
`commands to the device and obtaining feedback on its
`operation. The device comprises an independent power
`source 110, for example a non-chargeable battery or a
`chargeable battery. Asolar cell, which generates energy from
`a light source and is either connected to the device or
`integrated into it, may also be utilized for obtaining power.
`Other prior art methods of generating power for a portable
`device may also be employed, such as a small-size genera-
`tor, which produces power from movement and has been
`developed by watch producer Seiko®.
`
`[0012] The control unit 100 is usually implemented as a
`processor with software, but various hardware implementa-
`tions are also feasible, such as a circuit consisting of logic
`components or one or more application-specific integrated
`circuits ASIC. A hybrid of these implementations is also
`possible. In selecting the implementation, a person skilled in
`the art will pay attention to the requirements set for the size
`and power consumption of the device, the required process-
`ing capacity and the production costs and volumes.
`
`[0013] The user interface 102 of the device typically
`comprises a display 104, a means 106 for producing sound
`and a keyboard 108. The display 104 may be a liquid crystal
`display, for example, but it can also be implemented by any
`appropriate prior art display technique. The means 106 for
`producing sound may be a loudspeaker or a simpler means
`for producing beeps or other sound signals. The keyboard
`108 may even comprise a complete qwerty keyboard, a mere
`numeric keypad or only a few key buttons and/or rotary
`buttons. In addition, the user interface 102 may comprise
`other prior art user interface elements, for example various
`means for focusing a cursor (mouse,
`track ball, various
`arrow keys, etc.) or elements enabling audio control.
`
`[0014] The device further comprises two different sensors
`coupled to the control unit 100: a temperature sensor 120 for
`measuring the ambient temperature and a humidity sensor
`122 for measuring the ambient humidity. Such sensors are
`available from various producers. For example, Sensirion
`AG (whose web pages are found at the address www.sen-
`sirion.com) produces combined temperature and humidity
`sensors for this purpose which are implemented on one
`integrated CMOS circuit (complementary metal-oxide semi-
`conductor circuit): the type of the surface mounting com-
`ponent is SHT1x and that of the component provided with
`a support SHT7x.
`
`[0015] Dependence information, which defines the tem-
`perature values of dew points corresponding to the humidity
`values, is stored in the device. The above-mentioned com-
`bine temperature and humidity sensors 120, 122 by Sen-
`sirion already include the logic required to define the dew
`point. The dependence information can also be stored in the
`control unit 100 of the device. In addition, the information
`can be saved as tables or mathematical
`formulae,
`for
`instance.
`
`In the following, a brief summary is given on the
`[0016]
`theoretical principles of determining a dew point. Air may
`
`3
`
`

`

`US 2004/0220738 A1
`
`Nov. 4, 2004
`
`contain only a certain maximum amount of water vapor,
`which is dependent on the air temperature. At a high
`temperature, air may contain more water vapor than at a low
`temperature. When air contains all the water it can retain, it
`is at a saturation point, i.e. its relative humidity is 100%. If
`the air temperature and humidity are measured,
`the dew
`point can be defined as the temperature to which the air
`temperature has to decrease so that air cannot retain all the
`water vapor. At the dew point, the humidity included in the
`air starts to condense into drops,
`i.e. a fog appears. An
`instrument called a psychometer is known to be used for
`determining the dew point. It comprises two standard ther-
`mometers in parallel: the bulb of one thermometer is in the
`air and the bulb of the other thermometer is in a wick wetted
`with water.
`
`[0017] When the air temperature in Celsius degrees Tc and
`the relative humidity in percentages RH are known, the dew
`point can be calculated by the following formulae, for
`example.
`
`[0018] The pressure E5 of saturated vapor is calculated by
`the formula:
`
`7 5*Tc
`
`(1)
`
`[0019] Next the real vapor pressure E of air is calculated
`by the formula
`
`
`_ RH *ES
`_
`100
`
`(2)
`
`[0020] Then the dew point in Celsius degrees Tdc can be
`calculated by the formula
`
`Tdc —
`
`—430,22 + 237,7 >1: lnE
`—lnE + 19,08
`
`(3)
`
`[0021] where InE means the natural
`number E.
`
`logarithm of
`
`[0022] For example, if we assume that the air temperature
`is 16.5 C and the relative humidity 47%, then formula 1
`gives 17.7 as the pressure of saturated vapor, formula 2 gives
`8.3 as the real vapor pressure, and finally, formula 3 gives
`4.3 C as the dew point. Consequently, if the air temperature
`drops from 15.6 Celsius degrees to 4.3 Celsius degrees, fog
`starts to form.
`
`[0023] After this theoretical description, we can return to
`the structure of the device shown in FIG. 1. The control unit
`
`100 is configured to monitor the rate of change of the
`measured temperature, to determine, on the basis of the rate
`of change,
`the moment when the measured temperature
`reaches the temperature value of the dew point correspond-
`ing to the measured humidity on the basis of the dependence
`information, and to provide a forecast on fog appearance in
`relation to the moment employing the user interface 102.
`
`[0024] The device of FIG. 1 thus functions in such a
`manner that it measures the relative humidity of air by a
`
`humidity sensor 122 and the air temperature by a tempera-
`ture sensor 120. After this, the device forms the dew point
`corresponding to the measured temperature and relative
`humidity. Then the device monitors the change rate of the air
`temperature employing the measurements carried out by the
`temperature sensor 120. Based on this change rate,
`the
`moment at which the air temperature reaches the dew point
`can be determined. Then a forecast can be provided on fog
`appearance in relation to this moment employing the user
`interface 102 of the device. Let us assume that
`in the
`
`example described above, where the starting temperature of
`air was 16.5 C and the dew point 4.3 C, the change rate of
`air temperature is 5 Celsius degrees per hour. In that case,
`the dew point is reached in 2.26 hours, i.e. in approximately
`two hours and sixteen minutes.
`
`[0025] FIG. 4 illustrates the prediction of fog appearance:
`the horizontal axis describes the course of time and the
`
`vertical axis the decrease in temperature. The device mea-
`sures the temperature T0 at moment to. The dew point TD is
`determined on the basis of this. The device monitors the
`
`change in temperature by measuring T1 as the temperature at
`moment t1 and T2 as the temperature ad moment t2. By
`calculating the temperature change AT within a certain time
`At, an estimate of how the temperature will drop can be
`formed. In FIG. 4, this first forecast is illustrated by a line
`where one point and one line alternate. The first forecast is
`linear as shown and the dew point TD is achieved at moment
`TF1. According to the first forecast, fog will thus appear at
`moment TF1.
`
`In an embodiment, the control unit 100 is config-
`[0026]
`ured to show the amount of time left until the predicted fog
`appears in the user interface 102. This can be implemented
`for example by showing a decreasing counter on the display
`104, the counter showing the time in hours and minutes
`within which fog will appear according to the forecast. The
`time when the fog will appear according to the forecast
`could also be shown on the display 104. In that case, the
`device could also include a clock 116, which would enable
`showing the actual time on the display 104. A separate clock
`circuit 116 is not necessarily needed, but when, for example,
`the control unit 100 is a processor with software, the clock
`can be implemented by forming the time by counting
`processor cycles by means of interruptions utilizing the
`software. If the device comprises a GPS receiver (Global
`Positioning System), the time information included in the
`GSP signal can be employed.
`
`In an embodiment, the control unit 100 is config-
`[0027]
`ured to warn of approaching fog using a sound signal
`implemented by the user interface 102. The closer the
`predicted moment when fog will appear is, the more fre-
`quently the control unit 100 can be configured to give sound
`signals: first a beep can be produced every ten minutes, for
`example, after which the frequency can be increased step-
`wise or directly so that a beep is given every minute and
`finally every half a minute, for instance. If the means 106 for
`producing sound is a loudspeaker, even clear words (either
`recorded words or words produced by a speech synthesizer)
`can be employed for warning of approaching fog.
`
`In an embodiment, the control unit 100 is config-
`[0028]
`ured to calculate the probability of fog appearance within a
`certain time based on a difference between the measured
`
`temperature and the temperature value of the dew point. In
`
`4
`
`

`

`US 2004/0220738 A1
`
`Nov. 4, 2004
`
`addition to the linear prediction described above, various
`heuristic rules, which will be described below, can be
`employed. The control unit 100 can be configured to present
`the probability of fog appearance as a percentage in the user
`interface 102. In an embodiment, the control unit 100 is
`configured to use one hour as the predetermined time. Thus,
`information according to which the probability of fog
`appearance within an hour is 90% can be shown on the
`display, for instance.
`
`[0029] There may be various heuristic rules that may be
`applied separately or together in predicting fog, depending
`on the situation. In an embodiment, the control unit 100 is
`configured to take the time of the day into account in the
`monitoring of the temperature change rate. Temperature
`change rates in different seasons at certain places, e.g. at
`popular mountain climbing sites, can be stored in the control
`unit 100. In that case, the device should include calendar
`functions in addition to clock functions. According to a
`simple rule, the control unit 100 is configured to estimate
`that the direction of change in the temperature is descending
`and faster in the evening than in the day time: for example,
`in the afternoon the decrease rate of temperature may be 2
`C/hour and in the evening 4 C/hour.
`
`In an embodiment, the control unit 100 is config-
`[0030]
`ured to take the times of sunrise and sunset into account in
`
`monitoring the temperature change rate. The times of sunrise
`and sunset in certain areas may be stored in the control unit
`100. If the device is provided with a GPS receiver,
`the
`control unit 100 may automatically retrieve the times of
`sunrise and sunset corresponding to the positioned location
`and the date retrieved from the calendar. In an embodiment,
`the control unit 100 is configured to estimate that
`the
`temperature change rate is the highest at the sunrise and
`sunset. FIG. 4 illustrates this second forecast improved on
`the basis of the sunset time by a line where two dots and one
`line alternate. The sun sets at moment ts, after which the air
`temperature decreases linearly as in the first forecast but
`steeper. According to the second forecast, fog appears at
`moment TF2.
`
`In an embodiment, the device further comprises an
`[0031]
`air pressure sensor 124 coupled to the control unit 100 for
`measuring the ambient air pressure, and the control unit 100
`is configured to take account of the measured air pressure
`when monitoring the temperature change rate. The measured
`air pressure can be utilized by configuring the control unit
`100 to estimate the cloudiness of the weather on the basis of
`
`the measured air pressure, for instance. According to a very
`rough rule, low air pressure would mean cloudy weather and
`high air pressure sunny weather. In an embodiment,
`the
`control unit 100 is configured to estimate that the tempera-
`ture change rate is lower in cloudy weather than in sunny
`weather. In an embodiment, the control unit 100 is config-
`ured to estimate that the temperature change rate is slower
`when the sun sets in cloudy weather than when the sun sets
`in sunny weather.
`
`attaching the device to the wrist. The portable personal
`device may also be a sports watch intended to be used as an
`instrument
`in sports, hiking, sailing, mountain climbing
`and/or in snow sports. The sports watch may comprise an
`electronic compass 118 as shown in FIG. 1. Sports watches
`are produced by Suunto®), for example (web pages at the
`address www.suunto.com).
`
`[0033] The device may also be a heart rate monitor for
`measuring the user’s heart rate, and possibly other param-
`eters that can be measured non-invasively (such as blood
`pressure). In that case, the device comprises a heart rate
`measuring unit 112 shown in FIG. 1. In US. Pat. No.
`4,625,733, Séiynéij akangas describes a wireless and continu-
`ous heart rate monitoring concept where a transmitter to be
`attached to the user’s chest measures the user’s ECG-
`
`accurate (electrocardiogram) heart rate and transmits the
`heart
`rate information telemetrically to the heart
`rate
`receiver attached to the user’s wrist using magnetic coils in
`transmission. The heart rate monitor can also be imple-
`mented so that,
`instead of the solution consisting of a
`transmitter/receiver, the heart rate is measured directly from
`the wrist based on the pressure, for example. Other prior art
`methods for measuring the heart rate may also be employed,
`provided that they are suitable for use in a portable personal
`data processing device.
`
`[0034] Polar Electro® (web pages at the address www-
`.polar.fi) designs and manufactures heart
`rate monitors
`which comprise an electrode transmitter belt worn around
`the chest and an actual heart rate monitor worn on the wrist.
`The electronics unit in the electrode transmitter belt receives
`heart rate information from electrodes, which are used for
`measuring one or more parameters of the heart rate infor-
`mation. From the electrodes, the signal is transmitted to an
`ECG preamplifier, from which the signal is supplied to a
`transmitter via an AGC amplifier (Automatic Gain Control)
`and a power amplifier. The transmitter may be implemented
`as a coil, which transmits the heart rate information induc-
`tively to the receiver. For example, one burst of 5 kHz or a
`group of several bursts may correspond to one heartbeat.
`Information may be transmitted inductively or using another
`appropriate prior art data transmission method, for example
`over radio waves, optically or via a conduit. The receiver of
`the actual heart rate monitor can be implemented as a
`receiving coil, from which the received signal is transmitted
`via the signal receiver to the control unit 100, which controls
`and coordinates the function of the different components of
`the heart rate monitor. The heart rate monitor often com-
`
`prises an interface 126 between the heart rate monitor and
`the outside world.
`Information stored in the heart rate
`monitor can be transmitted via the interface 126 to further
`
`processing, for example to a personal computer. The soft-
`ware of the heart rate monitor can also be updated via the
`interface 126. Furthermore, information required by some
`embodiments, e.g. information on the sunrise and sunset
`times, can be loaded into the heart rate monitor via the
`interface 126.
`
`for
`[0032] The device described in FIG. 1 may be,
`example, a wrist-worn measuring device shown in FIG. 2.
`In the wrist-worn measuring device, the electronics compo-
`nents shown in FIG. 1, such as keys 108 and liquid crystal
`display 104 illustrated in FIG. 2, are protected by a cover
`200 (which is usually waterproof). In addition, the wrist-
`worn measuring device comprises a wristband 202, 204 for
`
`[0035] The device described in FIG. 1 may also be a
`subscriber terminal of a radio system illustrated in FIG. 3,
`for example a GSM (Global System for Mobile Communi-
`cations) or a UMTS (Universal Mobile Telecommunications
`System) terminal. In that case, the electronics components/
`parts illustrated in FIG. 1 are arranged inside a protective
`cover 300. In addition, here the device comprises a radio
`
`5
`
`

`

`US 2004/0220738 A1
`
`Nov. 4, 2004
`
`transceiver 112 as shown in FIG. 1 for implementing a
`bidirectional circuit-switched or packet-switched radio con-
`nection to a base station of the system. Using this radio
`connection, information required by some embodiments, for
`example sunrise and sunset times, can be loaded into the
`subscriber terminal. If the control unit 100 of the device also
`
`includes a browser, the device user may retrieve required
`data from the web pages of the device producer using the
`radio connection, for instance.
`
`[0036] Even though the invention was described above
`with reference to an example according to the accompanying
`drawings, it is clear that the invention is not limited to it but
`it may be modified in various ways within the attached
`claims.
`
`1. Aportable personal data processing device comprising
`
`a control unit for controlling the device,
`
`a user interface coupled to the control unit for giving
`commands to the device and obtaining feedback on its
`the operation,
`
`a temperature sensor coupled to the control unit for
`measuring the ambient temperature,
`
`a humidity sensor coupled to the control unit for measur-
`ing the ambient humidity, and
`
`dependence information, which defines temperature val-
`ues of the dew points corresponding to the humidity
`values, is stored in the device, and
`
`the control unit is configured to monitor the change rate
`of the measured temperature, to determine, on the basis
`of the change rate, the moment at which the tempera-
`ture reaches the temperature value of the dew point
`corresponding to the measured humidity on the basis of
`the dependence information, and to provide a forecast
`on fog appearance in relation to the moment employing
`the user interface.
`
`2. Adevice according to claim 1, wherein the control unit
`is configured to show the time left until the predicted fog
`appearance in the user interface.
`3. Adevice according to claim 1, wherein the control unit
`is configured to warn of approaching fog employing a sound
`signal implemented by the user interface.
`4. A device according to claim 3, wherein the closer the
`predicted moment when fog will appear is, the more fre-
`quently the control unit is configured to provide a sound
`signal by means of the user interface.
`5. Adevice according to claim 1, wherein the control unit
`is configured to calculate the probability of fog appearance
`
`within a certain time on the basis of a difference between the
`
`measured temperature and the temperature value of the dew
`point.
`6. Adevice according to claim 5, wherein the control unit
`is configured to show the probability of fog appearance as a
`percentage in the user interface.
`7. Adevice according to claim 5, wherein the control unit
`is configured to use one hour as the predetermined time.
`8. Adevice according to claim 1, wherein the control unit
`is configured to take the time of the day into account in
`monitoring the temperature change rate.
`9. Adevice according to claim 8, wherein the control unit
`is configured to estimate that the direction of temperature
`change is descending and faster in the evening than in the
`day time.
`10. Adevice according to claim 1, wherein the control unit
`is configured to take the sunrise and sunset
`times into
`account in monitoring the temperature change rate.
`11. A device according to claim 10, wherein the control
`unit is configured to estimate that the temperature change
`rate is higher at the sunrise and sunset.
`12. A device according to claim 1, wherein the device
`further comprises an air pressure sensor coupled to the
`control unit for measuring the ambient air pressure, and the
`control unit is configured to take the measured air pressure
`into account in monitoring the temperature change rate.
`13. A device according to claim 12, wherein the control
`unit is configured to estimate the cloudiness of the weather
`on the basis of the measured air pressure.
`14. A device according to claim 13, wherein the control
`unit is configured to estimate that the temperature change
`rate is lower in cloudy weather than in sunny weather.
`15. A device according to claim 13, wherein the control
`unit is configured to estimate that the temperature change
`rate is lower when the sun sets in cloudy weather than when
`the sun sets in sunny weather.
`16. A device according to claim 1, wherein the portable
`personal device is a wrist-worn measuring device.
`17. A device according to claim 1, wherein the portable
`personal device is a heart rate monitor.
`18. A device according to claim 1, wherein the portable
`personal device is a subscriber terminal of a radio system.
`19. A device according to claim 1, wherein the portable
`personal device is a sports watch for use as an instrument in
`sports, hiking, sailing, mountain climbing and/or in snow
`sports.
`
`6
`
`