CN109696190B - Method for measuring rotation delay of VR helmet based on gradient coding - Google Patents
Method for measuring rotation delay of VR helmet based on gradient coding Download PDFInfo
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- 238000005259 measurement Methods 0.000 description 3
- 238000012935 Averaging Methods 0.000 description 2
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- 230000009286 beneficial effect Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
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- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
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Abstract
The invention discloses a rotation delay measuring method of a VR helmet based on gradual change coding, which adopts a turntable to drive the VR helmet to rotate, wherein a light coding disc is arranged below the VR helmet and is divided into fan-shaped areas at equal intervals, and the fan-shaped areas are filled with gray gradual change patterns; the photosensitive sensor senses the light intensity of the gradually-changed patterns, and the VR helmet senses the rotation angle of the VR helmet when sensing the boundary of two adjacent patterns; when the VR helmet moves again and senses that the VR helmet rotates to the angle of the boundary of the pattern, inputting a corresponding black-and-white image to the VR helmet according to the color of the pattern, and sensing the black-and-white image by using a photosensitive sensor; obtaining a square wave curve obtained according to the gray level gradient pattern and a square wave curve output when the photosensitive sensor senses a black-white image, so that the delay time of the VR helmet can be obtained; the method enables the black and white patterns in the VR helmet and the gray scale gradient pattern codes of the VR helmet to be subjected to virtual and real registration, and errors caused by manual waveform alignment in an early method are avoided.
Description
Technical Field
The invention belongs to the technical field of virtual reality equipment, and particularly relates to a gradual change coding-based rotation delay measurement method for a VR helmet.
Background
The delay time of a VR helmet is closely related to the user experience, and if the delay time is slightly longer, it may cause the user to have "motion sickness" symptoms. The document Luca M d.new Method to Measure End-to-End Delay of virtual Reality [ M ] MIT Press,2010 "proposes a simple scheme of Delay measurement, as shown in fig. 1(a), a light-sensitive sensor is fixed on each of the VR helmet shell and the window, a test chart with gradually changed gray scale is displayed on both the display screen and the VR helmet, then the light-sensitive sensor on the shell is tightly attached to the display screen, the VR helmet is tightly attached to the display screen and reciprocates along the direction of the gray scale change, and the waveforms returned by the two sensors are recorded (fig. 1 (b)). The delay time of the VR headset is obtained by calculating the phase difference between the two waveforms. The method has the defects that manual movement is needed, and jitter and the like in the moving process can introduce a lot of noise to the signal processing at the rear part; the method for manually aligning the frequency domain waveform solves the problem of errors caused by asynchronism between the pattern in the virtual space and the pattern in the display screen, and for the tiny time of delay time, the method sometimes cannot eliminate the errors but introduces new errors; the test method has a VR headset for the headset, which needs to be able to calculate its own position data with so much shadowing that is not friendly to the tracking scheme of many VR headsets; the resulting data has large variance and its instability dictates that it cannot be used to make a measurement instrument.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a rotation delay measuring method for a VR headset based on gradient coding, which can accurately measure the rotation delay of the VR headset by a simple device.
A rotation delay measuring method of a VR helmet based on gradual change coding uses a measuring device which comprises a first photosensitive sensor (1), a VR helmet (2), an object stage (3), a rotary table (4), a controller (5), a light coding disc (6) and a second photosensitive sensor (7);
the optical coding disc (6) is divided into equally spaced fan-shaped areas, the fan-shaped areas are filled with gray level gradient patterns, and the gray level gradient rule of the gray level gradient patterns is as follows: starting from one side boundary of the sector area to the other side boundary, and continuously gradually changing the gray value along with the increase of the sector opening angle; the patterns of two adjacent areas are arranged in axial symmetry by taking the boundary as an axis;
the object stage (3) is fixed on a central rotating shaft extending out of the rotary table (4), the rotary table (4) is controlled by the controller (5) to rotate, and the VR helmet (2) can be driven by the object stage (3) to rotate coaxially with the rotary table (4); the second photosensitive sensor (7) is fixed on a display window of the VR helmet (2) and used for sensing the color of the pattern displayed by the VR helmet (2); the optical coding disc (6) is arranged below the object stage (3) and is supported by the bracket; the first photosensitive sensor (1) is fixed on the object stage (3), a photosensitive head faces downwards, can sense the pattern color on the light coding disc (6), and returns an analog voltage signal according to the gray value of the color;
the rotation delay measuring method comprises the following specific steps:
and 5, the VR helmet (2) displays a corresponding black-and-white picture according to the previously recorded rotation angle data set and by combining the calculated current angle information of the VR helmet (2), namely: when the calculated rotation angle is a white-to-black rotation angle, outputting a white pattern to the VR helmet (2); when the calculated rotation angle is a black-to-white rotation angle, outputting a black pattern to the VR helmet (2); the second photosensitive sensor (7) senses the black and white image output by the lens of the VR helmet (2) in the process, when the white image is sensed, the second photosensitive sensor (7) returns to a high level, and when the black image is sensed, the second photosensitive sensor (7) returns to a low level, so that a square wave signal is obtained and is called as a detection waveform;
and 7, calculating the time delay delta t of the detected waveform relative to the reference waveform, namely the time delay of the VR helmet (2).
Furthermore, the VR helmet (2) is rotated for a plurality of circles to obtain more waveform data, time delay delta t is respectively obtained, and the average value of the time delay delta t is the accurate time delay of the VR helmet (2).
The invention has the following beneficial effects:
the invention discloses a rotation delay measuring method of a VR helmet based on gradual change coding, which adopts a turntable to drive the VR helmet to rotate, wherein a light coding disc is arranged below the VR helmet and is divided into fan-shaped areas at equal intervals, and the fan-shaped areas are filled with gray gradual change patterns; the photosensitive sensor senses the light intensity of the gradually-changed patterns, and the VR helmet senses the rotation angle of the VR helmet when sensing the boundary of two adjacent patterns; when the VR helmet moves again and senses that the VR helmet rotates to the angle of the boundary of the pattern, inputting a corresponding black-and-white image to the VR helmet according to the color of the pattern, and sensing the black-and-white image by using a photosensitive sensor; obtaining a square wave curve obtained according to the gray level gradient pattern and a square wave curve output when the photosensitive sensor senses a black-white image, so that the delay time of the VR helmet can be obtained; the method enables the black and white patterns in the VR helmet and the gray scale gradient pattern codes of the VR helmet to be subjected to virtual and real registration, and errors caused by manual waveform alignment in an early method are avoided.
Drawings
Fig. 1(a) is a diagram of a conventional experimental apparatus for measuring VR headset movement delay;
FIG. 1(b) is a graph of experimental signals obtained based on the experimental set-up of FIG. 1 (a);
FIG. 2 is a schematic view of a measuring device according to the present invention;
FIG. 3 is a schematic view of the installation of a VR headset and a second light sensor in accordance with the present invention;
FIG. 4 is a schematic view of a code wheel;
FIG. 5(a) is a diagram of a detection waveform fed back by a second photosensor; fig. 5(b) is a sine wave signal fed back by the first photosensor, and fig. 5(c) is a reference waveform diagram converted from the sine wave signal;
fig. 6 is a schematic diagram of a delay between a reference waveform and a detected waveform.
Wherein, 1-a first photosensitive sensor, 2-a head-mounted display device, 3-an objective table, 4-a turntable, 5-a controller, 6-an encoding disc and 7-a second photosensitive sensor.
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
The invention discloses a rotation delay measuring method of a VR helmet based on gradual change coding, and a measuring device used in the method is shown in figure 2 and comprises a first photosensitive sensor 1, a VR helmet 2, an object stage 3, a rotary table 4, a controller 5, a coding disc 6, a second photosensitive sensor 7 and an upper computer.
As shown in fig. 4, the optical encoding disk 6 is divided into equally spaced sector areas, and the sector areas are filled with gray scale gradation patterns, wherein the gray scale gradation rules of the gray scale gradation patterns are as follows: the gray value changes gradually from one side boundary to the other side boundary of the sector area, and the gray value can be increased or decreased with the increase of the sector angle. The patterns of two adjacent areas are arranged in axial symmetry by taking the boundary as an axis.
The object stage 3 is fixed on a central rotating shaft extending out of the rotary table 4, the rotary table 4 is controlled by the controller 5 to rotate, and the VR helmet 2 can be driven by the object stage 3 to rotate coaxially with the rotary table 4; as shown in fig. 3, a second photosensor 7 is fixed on the display window of the VR headset 2 for sensing the color of the pattern displayed by the VR headset 2. The optical code wheel 6 is placed under the stage 3 and supported by a support. The first photosensitive sensor 1 is fixed on the object stage 3, the photosensitive head faces downwards, can sense the pattern color on the light coding disc 6, and returns an analog voltage signal according to the gray value of the color.
The rotation delay measuring method comprises the following specific steps:
1. firstly, the turntable 4 is controlled to move at a constant speed for one circle from an initial position (the boundary of any two adjacent sector areas), at the moment, no image is input into the VR helmet 2, but the self-rotation angle is calculated at any moment;
2. in the rotation process of the objective table 3, the first photosensitive sensor 1 senses the gray-scale gradient pattern on the encoding disc 6 and generates a voltage analog signal according to the gray-scale value of the pattern; at the moment of sensing the maximum value and the minimum value of the signal, the VR helmet 2 calculates the self rotation angle at each moment and records the self rotation angle; the rotation angles include two rotation angles, the maximum value corresponds to the black-to-white rotation angle at the moment, and the minimum value corresponds to the white-to-black rotation angle at the moment.
3. After the rotary table finishes one circle of rotation, a group of rotation angle data sets of the VR helmet 2 is finally obtained;
4. then the rotary table 4 is controlled to rotate from the initial position again, and simultaneously data returned by the first photosensitive sensor 1 and the second photosensitive sensor 7 are recorded;
5. the VR headset 2 combines the calculated current angle information of the VR headset 2 according to the previously recorded rotation angle data set, and the VR headset 2 displays a corresponding black-and-white picture, that is: when the calculated rotation angle is a white-to-black rotation angle, outputting a white pattern to the VR helmet 2; outputting a black pattern to the VR helmet 2 when the calculated rotation angle is a black-to-white rotation angle; the second photosensor 7 thereon senses a black-and-white image output from the lens of the VR headset 2 in the process, and when a white image is sensed, the second photosensor 7 returns to a high level, and when a black image is sensed, the second photosensor 7 returns to a low level, thereby obtaining a square wave signal, which is referred to as a detection waveform, as shown in fig. 5 (a).
6. Meanwhile, the first photosensitive sensor 1 senses the gray gradient pattern on the encoding disk 6 and generates a voltage analog signal according to the gray value of the pattern; thereby obtaining a sine wave signal as shown in fig. 5(b), and then converting it into a square wave signal as a reference waveform as shown in fig. 5 (c);
7. data processing: since there is a time delay in the perception of the VR headset 2, when the stage 3 is rotated to a certain position, the VR headset 2 cannot immediately perceive the position, and there is a time delay, therefore, as shown in fig. 6, the detected waveform will have a time delay Δ t relative to the reference waveform; therefore, calculating the time delay Δ t yields the movement delay of the VR headset 2. By averaging the multiple time delays Δ t on the detected waveform and the reference waveform, a more accurate movement delay of the VR headset 2 can be obtained.
In order to increase the data amount of multiple averaging and obtain more accurate measurement values, the VR headset 2 should be rotated several turns to obtain more waveform data, and respectively obtain Δ T, and the average value is the delay time T of the device.
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (2)
1. A method for measuring the rotation delay of a VR helmet based on gradual change coding is characterized in that a measuring device used by the method comprises a first photosensitive sensor (1), the VR helmet (2), an object stage (3), a rotary table (4), a controller (5), a light coding disc (6) and a second photosensitive sensor (7);
the optical coding disc (6) is divided into equally spaced fan-shaped areas, the fan-shaped areas are filled with gray level gradient patterns, and the gray level gradient rule of the gray level gradient patterns is as follows: starting from one side boundary of the sector area to the other side boundary, and continuously gradually changing the gray value along with the increase of the sector opening angle; the patterns of two adjacent areas are arranged in axial symmetry by taking the boundary as an axis;
the object stage (3) is fixed on a central rotating shaft extending out of the rotary table (4), the rotary table (4) is controlled by the controller (5) to rotate, and the VR helmet (2) can be driven by the object stage (3) to rotate coaxially with the rotary table (4); the second photosensitive sensor (7) is fixed on a display window of the VR helmet (2) and used for sensing the color of the pattern displayed by the VR helmet (2); the optical coding disc (6) is arranged below the object stage (3) and is supported by the bracket; the first photosensitive sensor (1) is fixed on the object stage (3), a photosensitive head faces downwards, can sense the pattern color on the light coding disc (6), and returns an analog voltage signal according to the gray value of the color;
the rotation delay measuring method comprises the following specific steps:
step 1, firstly, controlling a rotary table (4) to move at a constant speed for a circle from an initial position, and constantly calculating the rotation angle of a VR helmet (2);
step 2, in the rotation process of the objective table (3), the first photosensitive sensor (1) senses the gray gradient pattern on the encoding disc 6 and generates a voltage analog signal according to the gray value of the pattern; at the moment of sensing the maximum value and the minimum value of the signal, the VR helmet (2) calculates the self rotation angle at each moment and records the self rotation angle; the rotation angles comprise two rotation angles, the maximum value moment corresponds to a black-to-white rotation angle, and the minimum value moment corresponds to a white-to-black rotation angle;
step 3, after the rotary table finishes one circle of rotation, finally obtaining a group of rotation angle data sets of the VR helmet (2);
step 4, controlling the rotary table (4) to rotate from the initial position again, calculating the self-rotating angle of the VR helmet (2) at any moment, and simultaneously starting to record data returned by the first photosensitive sensor (1) and the second photosensitive sensor (7);
and 5, the VR helmet (2) displays a corresponding black-and-white picture according to the previously recorded rotation angle data set and by combining the calculated current angle information of the VR helmet (2), namely: when the calculated rotation angle is a white-to-black rotation angle, outputting a white pattern to the VR helmet (2); when the calculated rotation angle is a black-to-white rotation angle, outputting a black pattern to the VR helmet (2); the second photosensitive sensor (7) senses the black and white image output by the display window of the VR helmet (2) in the process, when the white image is sensed, the second photosensitive sensor (7) returns to a high level, and when the black image is sensed, the second photosensitive sensor (7) returns to a low level, so that a square wave signal is obtained and is called as a detection waveform;
step 6, at the same time, the first photosensitive sensor (1) senses the gray gradient pattern on the coding disc 6 and generates a voltage analog signal according to the gray value of the pattern; thus obtaining a sine wave signal, and then converting the sine wave signal into a square wave signal as a reference waveform;
and 7, calculating the time delay delta t of the detected waveform relative to the reference waveform, namely the time delay of the VR helmet (2).
2. The method for measuring the rotation delay of the VR headset based on the gradual change coding as claimed in claim 1, wherein the VR headset (2) is rotated for several turns to obtain more waveform data, and the time delays Δ t are obtained respectively, and the average value of the time delays Δ t is the accurate time delay of the VR headset (2).
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| CN110442011A (en) * | 2019-07-29 | 2019-11-12 | 中国计量大学 | A kind of method that can continuously detect virtual reality device dynamic delay and the time-delay detection system using this method |
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| JP2006171637A (en) * | 2004-12-20 | 2006-06-29 | Canon Inc | Head-mounted video display apparatus |
| US10018847B2 (en) * | 2015-10-28 | 2018-07-10 | Honeywell International Inc. | Methods of vestibulo-ocular reflex correction in display systems |
| EP3376772B1 (en) * | 2015-11-12 | 2023-01-25 | Panasonic Intellectual Property Corporation of America | Display method, program and display device |
| CN105807602A (en) * | 2016-03-10 | 2016-07-27 | 北京小鸟看看科技有限公司 | Method and system for testing virtual reality equipment delay |
| CN105954007B (en) * | 2016-05-18 | 2018-10-02 | 杭州映墨科技有限公司 | Delay test system and method for virtual implementing helmet acceleration movement |
| CN107687932B (en) * | 2016-08-05 | 2020-08-04 | 成都理想境界科技有限公司 | Method and device for detecting delay of head-mounted display equipment |
| CN106325517A (en) * | 2016-08-29 | 2017-01-11 | 袁超 | Target object trigger method and system and wearable equipment based on virtual reality |
| US10565916B2 (en) * | 2016-09-09 | 2020-02-18 | Kt Corporation | Providing streaming of virtual reality contents |
| CN106644396B (en) * | 2016-12-16 | 2019-06-25 | 捷开通讯(深圳)有限公司 | The detection device and detection method of the delay time of VR glasses |
| US9807384B1 (en) * | 2017-01-13 | 2017-10-31 | Optofidelity Oy | Method, apparatus and computer program product for testing a display |
| CN106951370B (en) * | 2017-03-17 | 2021-01-26 | 深圳普瑞赛思检测技术有限公司 | Evaluation method and device for virtual reality equipment program running delay |
| CN107423212B (en) * | 2017-03-17 | 2020-12-01 | 深圳普瑞赛思检测技术有限公司 | Method and device for evaluating response delay of screen of virtual reality equipment |
| CN207248488U (en) * | 2017-10-18 | 2018-04-17 | 宁波神州泰岳锐智信息科技有限公司 | For testing the revolution speed control device of VR equipment delay |
| CN107820075A (en) * | 2017-11-27 | 2018-03-20 | 中国计量大学 | A kind of VR equipment delayed test devices based on light stream camera |
| CN208156648U (en) * | 2018-02-11 | 2018-11-27 | 深圳创维新世界科技有限公司 | Time delay measurement instrument |
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