JP2009224969A - Method of determining orientation by using gravity sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of determining the orientation of housing provided with two parallel panels by using a gravity sensor. <P>SOLUTION: First, a set of element amount of gravity on three coordinates is obtained from a three-dimensional gravity sensor. When -0.5 g>g<SB>Z</SB>≥-1 g and 1 g≥g<SB>Z</SB>>0.5 g, the respective first direction status and second direction status are obtained. When 0.5 g≥g<SB>Z</SB>≥-0.5 g, it is necessary to depend on two parameters, g<SB>Z</SB>polarity and a size of element amount on the y axis (g<SB>Y</SB>) for further determination. When g<SB>Z</SB>>0 and -0.5 g>g<SB>Y</SB>≥-1 g, or when g<SB>Z</SB><0 and 1 g≥g<SB>Y</SB>>0.5 g, the determination result is the first direction status. When g<SB>Z</SB><0 and -0.5 g>g<SB>Y</SB>≥-1 g, or when g<SB>Z</SB>>0 and 1 g≥g<SB>Y</SB>>0.5 g, the determination result is the second direction status. The other cases may be determined "not related". <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a technique for determining the directionality of an apparatus by gravity detection, particularly gravity detection.

SideShow used in mobile phones, portable multimedia players (PMP), remote control, MPS players, personal digital assistants, digital cameras, GPS, electronic dictionaries, Microsoft Vista OS with significant advances in battery and semiconductor technology Many types of portable devices, such as devices, are well known. It is very confusing and inconvenient for a user to carry or use various personal portable devices. For this reason, integration attempts that combine two are adopted by many conventional portable devices, such as a combination of SideShow devices and remote control, or a combination of mobile phones and PMP. Typically, these two-in-one devices comprise two combination system keypads on two opposing sides of the cubic housing, respectively. In order to operate one of the two systems facing the user, the user can unintentionally press the keypad on the back side of another system that is not operated when holding the two devices in the palm of their hand The nature is very high. Therefore, undesired operations and unnecessary power consumption of the battery will occur.

Because the switch prevents the user's intentional operation to the disabled keypad, they switch the keypad on either side to operate and the switch to switch the other side keypad to operate. Providing is necessary for those portable devices with a double-sided keypad arrangement. The switch employs either a manual method or an automatic method. The manual method is executed by manual operation applied to the mechanical switch. This is inconvenient. The automatic method uses a gravity sensor to detect the direction of the portable device in order to determine whether the one-side keypad is upward. The determined upward keypad belongs to the system in use by the user. Thus, the keypad is automatically operable and the other keypad is inoperable at the same time. However, all the conventional methods for determining the directionality by using the gravity sensor have to perform an accurate and complicated calculation on the element amount on the three-dimensional orthogonal coordinate axis in order to obtain the determination result. Such calculations require a high performance microprocessor to perform. Not only are these microprocessors large in size but also expensive, they are not suitable for small devices or inexpensive products.

The main object of the present invention is to provide a method for determining directionality by utilizing a gravity sensor, which uses no element processing on three axes directly to determine directionality without any calculation processing. . Thus, the present invention can simplify the decision process and does not require a high performance microprocessor to perform. Furthermore, the present invention can be applied to a wider range.

To achieve the above objective, the method first receives a set of gravity element quantities on three coordinate axes from a three-dimensional gravity sensor. The measurement result of the first stage can be obtained from the element amount of the z axis (g _Z ). When −0.5 g> g _Z ≧ 1 g and 1 g ≧ g _Z > 0.5 g, the first direction state and the second direction state are obtained, respectively. If 0.5 g ≧ g _Z ≧ −0.5 g, this method relies on two parameters, g _Z polarity and element quantity on the y-axis (g _Y ), to make further decisions. When g _Y > 0 and −0.5 g> g _Y ≧ −1 g, or when g _Z <0 and 1 g ≧ g _Y > 0.5 g, the determination result is the first direction state. If g _Z <0 and −0.5 g> g _Y ≧ −1 g, or if g _Z > 0 and 1 g ≧ g _Y > 0.5 g, it is the second direction state. The rest is determined to be “irrelevant”, which means that the original state is maintained without switching.

First, referring to FIG. 1, a portable device having a double-sided keypad arrangement according to the principles of the present invention is shown. The device has a cubic housing 1 including a first panel 11 and a second panel 12 which are parallel to each other. Two keypads 111 and 121 are provided on the two panels 11 and 12, respectively. Of course, other elements such as indicators 112, 122 may be additionally provided on the panels 11, 12.

With respect to FIG. 2, it shows a preferred embodiment according to the present invention. The housing 1 has two independent systems, a first system 1a and a second system 1b. The two keypads 111 and 121 belong to the two systems 1a and 1b, respectively. As described above, the two keypads 111 and 121 are installed on two parallel sides of the housing, respectively. A gravity sensor 2 capable of detecting a gravity distribution along three orthogonal coordinate axes is disposed in the housing 1. The gravity sensor 2 is electrically connected to the control device 3. The gravity sensor 2 transmits a gravity signal reflecting the gravity distribution along the three orthogonal coordinate axes to the control device 3. In the embodiment as shown in FIG. 2, the output terminal of the control device 3 is electrically connected to the control terminals 41 a and 41 b of the relay 4. The inverter (NOT gate) 43 is disposed between the two control terminals 41a and 41b so that they are constantly opposed to each other. The two control terminals 41a and 41b control the switches 42a and 42b for opening and closing, respectively. The two switches 42a and 42b are electrically connected to the first keypad 111 and the second keypad 121, respectively. The control device 3 determines the directionality of the housing 1 based on the gravity signal from the gravity sensor 2, and then switches to the control terminals 41a and 41b of the relay 4 to enable and disable the two keypads 111 and 121, respectively. Output a signal. One skilled in the art will recognize that the phrase “operable” means that the keypads 111, 121 are available, and “inoperable” means they are not available. The two keypads 111 and 121 are always in the opposite state.

Referring to FIG. 3, let us assume that the portable device housing 1 is in a horizontal position, ie its first panel 11 and second panel 12 are parallel to the xy plane of the three-dimensional Cartesian coordinate system. Assume further that the first panel 11 is the front surface and the second panel 12 is the rear surface, that is, the z-axis faces the direction of the first panel 11. When the first panel 11 faces up to face the user (no display) and the second panel 12 faces down to face the ground (no display), gravity (-g) on the z-axis is illustrated. It will be detected as shown in 3A (it will be negative because gravity is in the opposite direction of the z-axis). Conversely, when the housing 1 is inverted at an angle of 180 °, the second panel 11 faces upward, and the first panel 11 faces downward, the z-axis becomes downward as shown in FIG. 3B. At this time, gravity is directed downward on the z-axis and the direction of gravity is the same as the z-axis, so gravity (+ g) on the z-axis will be detected. The control device 3 determines that either the first panel 11 or the second panel 12 is upward according to the principle, and further controls the relay 3 so that the upward keypads 111 and 121 can be operated and the downward keypad is disabled. can do.

4 and 5 are flowcharts of the determination method according to the present invention. First, the method starts from the gravity sensor 2 in step S1 with an element amount of gravity on the three-dimensional orthogonal coordinate axis, that is, an element amount on the x axis (g _X ), an element amount on the y axis (g _Y ), and a z axis. Receive the above element quantity (g _Z ):
The determination result of the first stage can be obtained from the magnitude of the gravity element amount on the z-axis (g _Z ) in step S2. More specifically, if g _Z is greater than 1 g or less than −1 g in steps S2a and S2e, that is, if the absolute value of g _Z is greater than 1 g, the method determines “not relevant” in step S4c. The phrase “not related” means that the original state is not changed. The value “1 g” is the first threshold value because the element amount on one single axis is not larger than 1 g or smaller than −1 g under the stationary state. Either greater than 1 g or less than −1 g means that the device is moving. At this time, the user should not operate the device and a switching state will not occur. However, the value 1g is a typical one of the first threshold values that cannot be changed. In fact, any value in the range between 1.2 g and 2 g can be selected as the first threshold. For example, 1.5 g can be another preferred value.

In step S2b, _{g Z} is less than -0.5G, the negative first threshold value (eg: -1g) If not smaller than, the method determines the first direction state in step S4a, i.e. first panel 11 or One of the second panels 12 faces upward. As an example, in FIG. 3, the first panel 11 is facing upward. In step S2d, if _{g Z} is not greater than the large positive first threshold value than 0.5g, the method determines that the second direction state at step S4b. The second direction state is the opposite of the first direction state, which is the other side panel facing up. In FIG. 3 as an example, the second panel 12 is facing upward. In step S2c, _{g Z} is not less than -0.5G, if not greater than 0.5g, in step S3 for the method further determination, the polarity of _{g Z} (i.e. positive or negative) and steps S31 and S32 in, it depends on two parameters of size g _Y element amount on the y-axis. That is the determination result of the second stage. _{G Z-negative} in S3N, _{g Y} is greater than 0.5g at step S31c, if not greater than the second threshold value, the method determines the first direction state at the step S4a. Similar to the first threshold, the second threshold is equal to or greater than 1 g, and values between 1.2 g and 2 g, in particular 1.5 g, can be used. _{G Z} is negative in step S3N, determines in step S31b, _{g Y} is less than -0.5G, if not less than a negative second threshold value, the method in step S4b, the second direction state. If g _Z is positive in step S3Y and g _Y is greater than 0.5 g in step S32c and not greater than the positive second threshold in step S32c, the method sets the second direction state in step S4b. Determined. In step S3y, _{g Z} is positive, at step S32b, _{g Y} is less than -0.5, if not less than a negative second threshold value, the method is determined that the first direction state at the step S4a. Further, if g _Z = 0 is included and g _Y is out of the above range in steps S31a and S32a, the method uniformly determines “not relevant”.

The above determination method only uses the magnitude of the gravitational element amount on three axes in order to obtain a determination result without calculation. Not only can the time required for the determination process be shortened, but also the required performance of the microprocessor can be reduced.

Embodiments of the present invention have been described. However, it will be understood that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.

Fig. 2 shows a portable device with a double-sided keypad arrangement in which the method of the invention is used. FIG. 2 shows a block diagram of the embodiment shown in FIG. It is a figure which shows the principle of the direction determination by this invention. The main part of the flowchart of the determination method by this invention is shown. Fig. 4 shows another part of the flow chart according to the present invention.

Explanation of symbols

1: Housing
4: Relay
11: Panel
12: Panel
41a: Control end
41b: Control end
42a: Switch
42a: Switch
43: Inverter
112: Display
122: Display

Claims (5)

a) receiving a gravity element amount on three orthogonal coordinate axes (g _X , g _Y , g _Z ) from the gravity sensor;
b) The determination result of the first stage is ensured by the magnitude of the element amount on the z-axis (g _Z ):
b1) If the absolute value is larger than the first threshold value not less than 1g of the g _Z, determines that "no relationship";
b2) wherein _{g Z} is less than -0.5G, if not less than the negative of the first threshold value, it determines that the first direction state;
b3) wherein _{g Z} is greater than 0.5g, if not greater than the positive first threshold value, determines that the second direction state;
b4) wherein _{g Z} is not greater than 0.5g, not less than -0.5G, without temporarily secure the determination result;
c) After the fourth step, secure the determination result of the second stage:
c1) at the _{g Z} is negative, the elements of the y-axis _{(g Y)} is greater than 0.5g, if not greater than the second threshold value not less than 1g, determines that the first direction state;
c2) at the _{g Z} is negative, the _{g y} is less than -0.5, if not less than the negative of the second threshold value, it determines that the second direction state;
c3) wherein _{g Z} is positive, the _{g Y} is greater than 0.5g, if not greater than the positive second threshold value, determines that the second direction state;
c4) wherein _{g Z} is positive, the _{g Y} is less than -0.5G, if not less than the negative of the second threshold value, it determines that the first direction state;
c5) Utilizing a gravity sensor consisting of each step of judging that “g _Y” is outside the range defined in the steps c1-c4 or “g _Z ” is “unrelated” when the g _Y is zero. Method for determining directionality by The method of claim 1, wherein the first threshold is between 1.2 g and 2 g. The method of claim 2, wherein the threshold is 1.5 g. The method of claim 1, wherein the second threshold is between 1.2 g and 2 g. The method of claim 4, wherein the second threshold is 1.5 g.