This application is based upon and claims the benefit of priority under 35 USC 119 of Japanese Patent Application No. 2011-071982 filed Mar. 29, 2011, the entire disclosure of which, including the description, claims, drawings, and abstract, is incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to an input apparatus and a contact state detection method.
2. Description of the Related Art
For example, as described in Jpn. Pat. Appln. KOKAI Publication No. 11-39087, an input apparatus is conventionally known in which, for example, a contact device of a stylus is slid on a surface of a contacted object such as a touch panel or paper to allow a trajectory of the contact device to be output to a display device. A stylus is known which incorporates an omnidirectional pressure sensitive sensor at a tip of a pen so as to detect a direction of resistance such as a frictional force which is applied directly to the pen tip by the contacted object during writing, based on a variation in pressure detected by the pressure sensitive sensor.
In the above-described stylus, the intensity of resistance such as a frictional force varies depending on the materials of the pen tip and the contacted object. It has thus been difficult to accurately detect a component of a writing pressure applied to the contacted object by the pen tip, which acts in a normal direction of the surface of the contacted object.
According to one aspect of the present invention, there is provided an input apparatus comprising: a contact device that includes: a shaft member; a first sensor configured to detect, when a tip of the shaft member comes into contact with a surface of a contacted object, a first force corresponding to a component of a force applied to the tip, which acts in a planar direction crossing a direction of an axis of the shaft at right angles; and a second sensor configured to detect a second force corresponding to a component of the applied force, which acts in a direction of the axis of the shaft member.
According to another aspect of the present invention, there is provided a contact state detection method comprising: detecting, when a tip of the shaft member comes into contact with a surface of a contacted object, a first force corresponding to a component of a force applied to the tip, which acts in a planar direction crossing a direction of an axis of the shaft at right angles; and calculating an angle of rotation by which the shaft member rotates around the axis of the shaft member, based on a result of the detection.
According to still another aspect of the present invention, there is provided a contact state detection method comprising: detecting, when a tip of the shaft member comes into contact with a surface of a contacted object, a first force corresponding to a component of a force applied to the tip, which acts in a planar direction crossing a direction of an axis of the shaft at right angles, and detecting a second force corresponding to a component of the applied force, which acts in a direction of the axis of the shaft member; and calculating a magnitude of the force applied to the surface of the contacted object by the tip of the shaft member, based on results of the detections.
According to still another aspect of the present invention, there is provided a contact state detection method comprising: detecting, when a tip of the shaft member comes into contact with a surface of a contacted object, a first force corresponding to a component of a force applied to the tip, which acts in a planar direction crossing a direction of an axis of the shaft at right angles, and detecting a second force corresponding to a component of the applied force, which acts in a direction of the axis of the shaft member; and calculating an angle between the shaft member and a plane passing through a contact point between the shaft member and the surface of the contacted object and contacting the surface of the contacted object, based on results of the detections.
Advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
Embodiments of the present invention will be explained with reference to the drawings. However, the embodiments described below involves various technically preferable limitations for implementing the present invention, the scope of the present invention is not limited to the embodiments and illustrated examples described below.
The contact device 2 is, for example, a stylus, and has a wired or wireless connection to the control device 5 for communication with the control device 5.
The main body 21 includes a grip portion 211 formed like a square pillar and gripped by a user and a tip 212 formed substantially like a quadrangular pyramid so as to taper from a tip of the grip portion 211. The grip portion 211 is internally hollow so as to include various built-in circuit components (not shown in the drawings). Furthermore, the grip portion 211 includes three partition walls 213, 214, 215 formed at the tip thereof and spaced at predetermined intervals. Of the three partition walls 213, 214, and 215, the tip-side partition wall 213 and the intermediate partition wall 214 include holes 216 and 217, respectively, formed therein to hold the pen tip 22. The hole 216 in the tip-side partition wall 213 is formed like a square pillar. Each of the inner surfaces of the hole 216 is parallel to a corresponding one of the outer side surfaces of the grip portion 211. The hole 217 in the intermediate partition wall 214 is formed like a cylinder.
On the other hand, an opening 218 through which the pen tip 22 is allowed to project is formed at a tip portion of the tip 212.
The pen tip 22 includes a shaft member 221, a first sensor 222, and a second sensor 223.
The shaft member 221 is substantially cylindrical, and a tip of the shaft member 221 is formed into a curved surface projecting further from the tip. The shaft member 221 is arranged inside the holes 216 and 217 so as to extend from the partition wall 215, located most inward, to the opening 218. The shaft member 221 is not limited to the substantially cylindrical shape but may be shaped to extend generally along the linear axis.
The second sensor 223 includes an axial-direction sensor configured to detect a component of a force applied to the shaft member 221, which acts in the direction of the axis L of the shaft member 221. The second sensor 223 is arranged to contact a proximal end of the shaft member 221 between the proximal end of the shaft member 221 and the partition wall 215, located most inward. Thus, the second sensor 223 can detect the component of the force applied to the shaft member 221, which acts in the direction of the axis L of the shaft member 221.
x=Tx/D (1)
A=√{square root over ( )}(x2+y2) (2)
θ=cos−1(x/A) (3)
Now, with reference to
Tx=√{square root over ( )}(Ta2+Tb2+Tc2+Td2) (4)
Force x is determined by substituting the rotating torque (−Tx) determined by Expression (4) into Expression (1) described above. Force A and the angle θ are determined by substituting force x obtained in this case and the above-described force y and into Expressions (2) and (3).
φ=tan−1(Tb/Ta) (5)
When the two adjacent first sensors arranged counterclockwise adjacent to each other as seen from the tip of the axis L detect components of the rotating torque, the components detected by the respective first sensors are denoted by Ta and TB in order in the counterclockwise direction. Furthermore, when the two first sensors 222a and 222b detect components of the rotating torque, a value determined by Expression (5) shown below is used directly as the angle of rotation φ. When the two first sensors 222b and 222c detect components of the rotating torque, the angle of rotation φ is determined by adding 90° to the value determined by Expression (5). Similarly, when the two first sensors 222c and 222d detect components of the rotating torque, the angle of rotation φ is determined by adding 180° to the value determined by Expression (5). When the two first sensors 222d and 222a detect components of the rotating torque, the angle of rotation φ is determined by adding 270° to the value determined by Expression (5).
As described above, based on the first detection result and the second detection result, the controller 26 calculates the magnitude of the force (force A) applied to the contacted object by the shaft member 221 and the angle θ between the shaft member 221 and a plane S related to the contacted object and passing through the contact point between the surface of the contacted object and the shaft member 221. At this time, the controller 26 serves as a second calculation unit and a third calculation unit. Furthermore, the controller 26 calculates the angle of rotation φ of the shaft member 221 based on the first detection result. At this time, the controller 26 serves as a first calculation unit.
Upon obtaining the results of the calculations, the controller 26 transmits the calculation results from interface 25 to the control device 5. At this time, the controller 26 and interface 25 serve as an information transmission unit.
The touch panel unit 31 is the contacted object with the surface thereof contacted by the tip of the shaft member 221. When the tip of the shaft member 221 comes into contact with the touch panel unit 31, the touch panel unit 31 outputs an electric signal corresponding to the contact position, to the controller 33. Based on the electric signal from the touch panel unit 31, the controller 33 detects the contact position where the tip of the shaft member 221 contacts the surface of the contacted object. The controller 33 then transmits second information containing the electric signal corresponding to the contact position, to the exterior by interface 32.
The display device 4 is, for example, a monitor and is electrically connected to interface 51 of the control device 5. The display device 4 provides display under the control of the control device 5. The display device 4 is arranged on the back side of the contacted device 3 as shown in
As shown in
The drawing effects include, for example, a line width changing effect of changing the thickness of a drawing line, a line color changing effect of changing the color of a drawing line, a line type changing effect of changing the type of a drawing line, and an erasing effect of erasing a temporarily drawn drawing line. Specifically, force A and the line width changing effect are associated with each other so that the thickness of the drawing line increases consistently with the magnitude of force A. Furthermore, the angle θ, the line width changing effect, the line color changing effect are associated with one another so that as the angle θ is closer to 90°, the drawing line becomes thinner and darker in color, whereas as the angle θ deviates further from 90°, the drawing line gradually becomes thicker and lighter in color.
Furthermore, the angle of rotation φ and the line type changing effect are associated with each other. One of the four side surfaces of contact device 2 which is located most upward can be detected based on the angle of rotation φ. Thus, if different line types are associated with the respective side surfaces, the angle of rotation φ corresponds to the line type associated with the side surface located most upward. For example, of the four side surfaces, a first side surface is assigned a “solid line”, a second side surface is assigned a “dashed line”, a third side surface is assigned an “alternate long and short dash line”, and a fourth side surface is assigned “erase”.
Now, operation of the present embodiment will be described below.
First, operation of the contact device 2 will be described.
In step S2, the controller 26 of the contact device 2 calculates force A, shown in
In step S3, the controller 26 of the contact device 2 calculates the angle θ, shown in
In step S4, the controller 26 of the contact device 2 calculates the angle of rotation φ based on the first detection result from each of the four first sensors 222.
In step S5, the controller 26 of the contact device 2 transmits first information including the results of the calculations from interface 25 to the control device 5.
Now, operation of the control device 5 will be described.
In step S12, the controller 52 of the control device 5 determines whether or not first information has been transmitted by the contact device 2. If the first information has been transmitted by the contact device 2, the controller 52 shifts to step 14. If the second information has not been transmitted by the contact device 2, the controller 26 shifts to step S13.
In step S13, the controller 52 of the control device 5 calculates the contact position based on the second information. The controller 52 then controls the display device 4 so that a drawing line with no drawing effect applied thereto is displayed on a display surface of the display device 4 at a position corresponding to the contact position.
In step S14, the controller 52 of the control device 5 reads force A from the first information, and determines to apply the drawing effect corresponding to force A.
In step S15, the controller 52 of the control device 5 reads the angle θ from the first information, and determines to apply the drawing effect corresponding to the angle θ.
In step S16, the controller 52 of the control device 5 reads the angle of rotation φ from the first information, and determines to apply the drawing effect corresponding to the angle of rotation φ.
In step S17, the controller 52 of the control device 5 calculates the contact position based on the second information. The controller 52 then controls the display device 4 so that a drawing line to which the drawing effect determined as described above has been applied is displayed on the display surface of the display device 4 at the position corresponding to the contact position.
For example,
As described above, according to the present embodiment, the first sensor 222 detects the component of the force applied to the tip of the shaft member 221, which acts in the planar direction orthogonal to the direction of the axis L of the shaft member 221. The second sensor 223 detects the component of the above-described force which acts in the direction of the axis L. Thus, force A can be calculated from the first detection result from the first sensor 222 and the second detection result from the second sensor 223. This allows force A applied to the contacted device 3 by the contact device 2 to be accurately detected.
Furthermore, with the first detection result from the first sensor 222 and the second detection result from the second sensor 223, the angle θ between the shaft member 221 and the plane S on the contacted object can be calculated.
The first detection result from the first sensor 222 also enables the angle of rotation φ of the shaft member 221 to be determined.
Then, when a figure is drawn at the position corresponding to the second information transmitted by the contacted device 3, the drawing effect associated with the results of calculation of force A, the angle θ, and the angle of rotation φ is applied to the figure. Thus, a different drawing effect can be reflected in the contents of display provided by the display device 4, simply by changing the state of the contact device 2 during drawing.
The present invention is not limited to the above-described embodiment and may be modified as needed.
For example, the controller 26 of the contact device 2 illustrated in the above-described embodiment has all the functions of the first, second, and third calculation units. However, the controller 52 of the contact device 5 may function as at least one of the first, second, and third calculation units. Furthermore, in the above-described embodiment, the first information transmitted to the exterior by the controller 26 of the control device 2 does not include the first detection result from the first sensor 222 or the second detection result from the second sensor 223. However, the first information may include the first detection result and the second detection result. Specific modifications will be described below.
If the controller 26 of the control device 2 has all the functions of the first, second, and third calculation units, the controller 26 of the control device 2 may transmit, in addition to all the calculation results from the first to third calculation units, the first detection result from the first sensor 222 and the second detection result from the second sensor 223 to the exterior as the first information. In this case, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto based not only on all the calculation results from at least the first to third calculation units but also on the first and second detection results.
If the controller 26 of the control device 2 has only the functions of the second and third calculation units, the controller 26 of the control device 2 may transmit, in addition to the two calculation results from the second and third calculation units, the first detection result from the first sensor 222 to the exterior as the first information. In this case, the controller 26 of the control device 2 may or may not transmit the second detection result from the second sensor 223 to the exterior as the first information. Furthermore, the controller 52 of the control device 5 has the function of the first calculation unit to calculate the angle of rotation φ of the shaft member 221. Moreover, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto, on the display device 4 based not only on all the calculation results from at least the second and third calculation units but also on the first detection result. If the controller 52 of the control device 5 receives the second information from the controller 26 of the contact device 2, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto, on the display device 4 based on the first or second detection result.
If the controller 26 of the control device 2 lacks the function of one of the second and third calculation units, the controller 26 of the control device 2 may transmit, in addition to all the calculation results from the calculation unit of the controller 26 of the control device 2, the first detection result from the first sensor 222 and the second detection result from the second sensor 223, to the exterior as the first information. In this case, the controller 52 of the control device 5 may have at least the function of the above-described one of the calculation units. That is, if the controller 26 of the control device 2 further lacks the function of the first calculation unit, the controller 52 of the control device 5 needs to have the function of the first calculation unit. In this case, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto, on the display device 4 based not only on the calculation result from the other of the second and third calculation units but also on the first and second detection results. If the controller 26 of the control device 2 has the function of the first calculation unit, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto, on the display device 4 based not only on the calculation result from the above-described other calculation unit but also on the calculation result from the first calculation unit.
Furthermore, the contact device 2 illustrated in the above-described embodiment incorporates the four first sensors 222. However, at least three first sensors 222 may be provided.
Additionally, in the case illustrated in the above-described embodiments, the display contents involve a drawing effect varying depending on the calculation results (force A, angle θ, and angle of rotation φ). Manipulation of an application other than the one for drawing may be assigned to the calculation results. This enhances the versatility of the contact device 2.
In addition, in the above-described embodiments, the angle of rotation φ is divided into four areas according to the magnitude of the angle so that each of the areas corresponds to one of the four side surfaces of the contact device 2. However, the angle of rotation φ may be divided into at most three or at least five areas according to the magnitude of the angle so that a function to apply any effect can be assigned to each area. That is, the number of segments into which the angle of rotation φ is divided may not be equal to that of the side surfaces of the contact device. Thus, the grip portion 211 may be, for example, cylindrical.
Furthermore, in the above-described embodiments, in step S11, the processing shifts to step S13 if the contact device 2 fails to transmit the first information. However, the processing may shift to step S13 if the value included in the first information is equal to or smaller than a predetermined value.
Additionally, in the above-described embodiments, the controller 52 of the control device 5 draws a figure with a drawing effect applied thereto, on the display device 4 based on all of the first to third calculation results (force A, angle θ, and angle of rotation φ). However, of course, the controller 52 of the control device 5 may draw a figure with a drawing effect applied thereto, on the display device 4 based exclusively on one or two of the first to third calculation results.
Several embodiments of the present invention have been described. However, the technical scope of the present invention includes the invention set forth in the claims and equivalents.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
Number | Date | Country | Kind |
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2011-071982 | Mar 2011 | JP | national |