CN215177589U - Angle measuring device based on rotary polaroid - Google Patents
Angle measuring device based on rotary polaroid Download PDFInfo
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- CN215177589U CN215177589U CN202120803137.6U CN202120803137U CN215177589U CN 215177589 U CN215177589 U CN 215177589U CN 202120803137 U CN202120803137 U CN 202120803137U CN 215177589 U CN215177589 U CN 215177589U
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Abstract
The utility model discloses an angle measuring device based on a rotary polaroid, which comprises a driving rotating shaft, two hollow shafts, three polaroids, a light source, two photoelectric sensors and a signal processing device; the two hollow shafts are respectively in transmission connection with the driving rotating shaft, and the transmission ratio is 2; the two polaroids are respectively arranged in the two hollow shafts and are positioned on the same radial plane; one end of the driving rotating shaft is connected with the rotating piece to be detected; the light source is positioned at one end of the driving rotating shaft and uniformly irradiates the two polaroids; the third polaroid is positioned at the other end of the active rotating shaft and is parallel to the two polaroids; the two photoelectric sensors are arranged on the third polarizer and respectively correspond to the two hollow shafts, and the signal processing device is respectively connected with the two photoelectric sensors. The utility model discloses rotation angle's measurement can be realized.
Description
Technical Field
The utility model relates to an angular measurement technical field especially relates to an angular measurement device based on rotatory polaroid.
Background
An angle sensor is a sensor that senses a measured angle and converts it into a usable output signal. An angle sensor is a large class of sensors, which can measure both an angle and acceleration, velocity, displacement of an object. The method has wide application in the fields of construction, mining industry, mechanical industry, military industry and the like.
The current angle sensor generally refers to a rotary encoder, a grating is installed on a shaft inside, the grating is cut through the rotation of the shaft, for example, for a 360-pulse product, 360 pulses are output every circle, one pulse represents 1 degree, and in addition, the absolute value type rotary encoder outputs signals which are fixed and correspond to the angle, binary, BCD or Gray codes are output, and the like. Another type of angle sensor is a hall type angle sensor, which detects a change in angle mainly by a magnetic field.
The utility model aims at providing a novel angular surveying device.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem that will solve is: the angle measuring device based on the rotary polaroid can realize the measurement of the rotating angle.
In order to solve the technical problem, the utility model discloses a technical scheme be: an angle measuring device based on a rotary polaroid comprises an active rotating shaft, a first hollow shaft, a second hollow shaft, a first polaroid, a second polaroid, a third polaroid, a light source, a first photoelectric sensor, a second photoelectric sensor and a signal processing device;
the first hollow shaft and the second hollow shaft are respectively in transmission connection with the driving rotating shaft, and the transmission ratio is 2; the first polaroid and the second polaroid are respectively arranged in the first hollow shaft and the second hollow shaft in a one-to-one correspondence manner and are positioned on the same radial plane; the included angle of the polarization directions of the first polarizer and the second polarizer is 45 degrees;
one end of the driving rotating shaft is connected with the rotating piece to be detected; the light source is positioned at one end of the driving rotating shaft and uniformly irradiates the first polaroid and the second polaroid; the third polaroid is positioned at the other end of the active rotating shaft and is parallel to the first polaroid and the second polaroid; the projection of the third polaroid on the same radial plane covers the active rotating shaft, the first hollow shaft and the second hollow shaft;
the first photoelectric sensor and the second photoelectric sensor are respectively arranged on one surface of the third polaroid, which is far away from the light source, and respectively correspond to the first hollow shaft and the second hollow shaft one by one; the signal processing device is respectively connected with the first photoelectric sensor and the second photoelectric sensor.
Furthermore, a first gear is arranged on the outer side surface of the driving rotating shaft, second gears are respectively arranged on the outer side surfaces of the first hollow shaft and the second hollow shaft, and the first gear is in transmission connection with the second gear; the ratio of the number of teeth of the second gear to the number of teeth of the first gear is 2.
Furthermore, the first photoelectric sensor and the second photoelectric sensor are respectively positioned on the extension lines of the central axes of the first hollow shaft and the second hollow shaft.
Further, an included angle between azimuth angles of the first hollow shaft and the second hollow shaft relative to the driving rotating shaft is 90 degrees.
Further, the signal processing device is an oscilloscope or an oscillograph tracker.
The beneficial effects of the utility model reside in that: when the rotating member to be tested rotates, the driving rotating shaft is driven to synchronously rotate, the driving rotating shaft drives the two hollow shafts to rotate, so that the polaroids fixed in the two hollow shafts rotate, the third polaroid is fixed, the included angle between the polaroids in the two hollow shafts and the polarization direction of the third polaroid continuously changes, and in the process, the light source continuously irradiates, so that the voltage signals collected by the two photoelectric sensors also periodically change. The rotation angle of the rotating member to be measured can be obtained by analyzing the two periodically changed voltage signals. The utility model discloses rotation angle's measurement can be realized.
Drawings
Fig. 1 is a schematic structural view of an angle detection device according to a first embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view taken along line A-A of FIG. 1;
FIG. 3 is a schematic cross-sectional view of FIG. 1 taken along line B-B of FIG. 2;
fig. 4 is a schematic view of polarization directions of three polarizers in an initial state according to an embodiment of the present invention;
fig. 5 is a schematic view of a voltage signal acquired by one rotation of the driving rotating shaft according to a first embodiment of the present invention;
fig. 6 is a schematic diagram of the voltage signal processed in fig. 5.
Description of reference numerals:
1. a driving rotating shaft; 21. a first hollow shaft; 22. a second hollow shaft; 31. a first polarizer; 32. a second polarizer; 33. a third polarizer; 4. a light source; 51. a first photoelectric sensor; 52. a second photoelectric sensor; 61. a first gear; 62. a second gear.
Detailed Description
In order to explain the technical content, the objects and the effects of the present invention in detail, the following description is made in conjunction with the embodiments and the accompanying drawings.
Referring to fig. 1, an angle measuring device based on a rotating polarizer includes an active rotating shaft, a first hollow shaft, a second hollow shaft, a first polarizer, a second polarizer, a third polarizer, a light source, a first photoelectric sensor, a second photoelectric sensor, and a signal processing device;
the first hollow shaft and the second hollow shaft are respectively in transmission connection with the driving rotating shaft, and the transmission ratio is 2; the first polaroid and the second polaroid are respectively arranged in the first hollow shaft and the second hollow shaft in a one-to-one correspondence manner and are positioned on the same radial plane; the included angle of the polarization directions of the first polarizer and the second polarizer is 45 degrees;
one end of the driving rotating shaft is connected with the rotating piece to be detected; the light source is positioned at one end of the driving rotating shaft and uniformly irradiates the first polaroid and the second polaroid; the third polaroid is positioned at the other end of the active rotating shaft and is parallel to the first polaroid and the second polaroid; the projection of the third polaroid on the same radial plane covers the active rotating shaft, the first hollow shaft and the second hollow shaft;
the first photoelectric sensor and the second photoelectric sensor are respectively arranged on one surface of the third polaroid, which is far away from the light source, and respectively correspond to the first hollow shaft and the second hollow shaft one by one; the signal processing device is respectively connected with the first photoelectric sensor and the second photoelectric sensor.
From the above description, the beneficial effects of the present invention are: the measurement of the rotation angle can be realized.
Furthermore, a first gear is arranged on the outer side surface of the driving rotating shaft, second gears are respectively arranged on the outer side surfaces of the first hollow shaft and the second hollow shaft, and the first gear is in transmission connection with the second gear; the ratio of the number of teeth of the second gear to the number of teeth of the first gear is 2.
As can be seen from the above description, when the two hollow shafts rotate for 1 cycle, the two photoelectric sensors will output voltage signals for 2 complete cycles. By setting the transmission ratio to be 2, the driving shaft rotates for 1 cycle, the two hollow shafts rotate for 0.5 cycle, and the two photoelectric sensors output voltage signals of 1 complete cycle; namely, the period of the voltage signals output by the three original photoelectric sensors is 180 degrees, and the period of the voltage signals is changed to 360 degrees by setting the transmission ratio to be 2.
Furthermore, the first photoelectric sensor and the second photoelectric sensor are respectively positioned on the extension lines of the central axes of the first hollow shaft and the second hollow shaft.
As can be seen from the above description, it is ensured that the two photoelectric sensors can acquire the optical signals sequentially passing through the polarizer and the third polarizer in the hollow shaft.
Further, an included angle between azimuth angles of the first hollow shaft and the second hollow shaft relative to the driving rotating shaft is 90 degrees.
Further, the signal processing device is an oscilloscope or an oscillograph tracker.
Example one
Referring to fig. 1-6, a first embodiment of the present invention is: an angle detection device based on a rotary polaroid can be applied to detecting a rotation angle.
As shown in fig. 1-3, the display device includes an active rotating shaft 1, two hollow shafts (a first hollow shaft 21 and a second hollow shaft 22, respectively), three polarizers (a first polarizer 31, a second polarizer 32, and a third polarizer 33, respectively), a light source 4, two photoelectric sensors (a first photoelectric sensor 51 and a second photoelectric sensor 52, respectively), and a signal processing device (not shown in the drawings).
As shown in fig. 1, the first hollow shaft 21 and the second hollow shaft 22 are respectively in transmission connection with the driving rotating shaft 1, and the transmission ratio is 2. Specifically, as shown in fig. 2, in the present embodiment, a first gear 61 is disposed on an outer side surface of the driving rotating shaft 1, second gears 62 are disposed on outer side surfaces of the first hollow shaft 21 and the second hollow shaft 22, respectively, the first gear 61 and the second gear 62 are in transmission connection, and a ratio of the number of teeth of the second gear 62 to the number of teeth of the first gear 61 is 2. Preferably, an included angle between azimuth angles of the first hollow shaft and the second hollow shaft relative to the driving rotating shaft is 90 °.
As shown in fig. 2, the first polarizer 31 and the second polarizer 32 are respectively disposed in the first hollow shaft 21 and the second hollow shaft 22 in a one-to-one correspondence manner, that is, the first polarizer 31 is disposed in the first hollow shaft 21, the second polarizer 32 is disposed in the second hollow shaft 22, and the first polarizer 31 and the second polarizer 32 are located on the same radial plane. Further, the included angle between the polarization directions of the first polarizer 31 and the second polarizer 32 is 45 °.
As shown in fig. 3, one end of the driving spindle 1 (i.e. the lower end in the figure) is connected to a rotating member to be tested (not shown in the figure), and when the rotating member to be tested rotates, the driving spindle 1 is synchronously driven to rotate. The light source 4 is located at one end of the active spindle 1, and uniformly irradiates the first polarizer 31 and the second polarizer (arrows in fig. 3 indicate light source irradiation directions). Preferably, the light source is a surface light source, and uniformly irradiates the same radial plane where the first polarizer and the second polarizer are located.
The third polarizer 33 is located at the other end of the active shaft 1 (without connection, that is, the third polarizer does not rotate along with the rotation of the active shaft), and is parallel to the first polarizer 31 and the second polarizer. Furthermore, the projection of the third polarizer on the same radial plane covers the active rotating shaft, the first hollow shaft and the second hollow shaft. That is, the size of the third polarizer should be able to cover the active rotating shaft and the two hollow shafts, so that the light passing through the polarizers in the two hollow shafts can both irradiate onto the third polarizer and be further polarized by the third polarizer. Preferably, the center point of the third polarizer 33 is located on an extension line of the central axis of the active spindle 1.
Referring to fig. 1, the first photo-sensor 51 and the second photo-sensor 52 are respectively disposed on a surface of the third polarizer 33 away from the light source 4, and respectively correspond to the first hollow shaft 21 and the second hollow shaft 22 one by one. Further, the first photoelectric sensor 51 and the second photoelectric sensor 52 are respectively located on the extension lines of the central axes of the first hollow shaft 21 and the second hollow shaft 22, so that the two photoelectric sensors can acquire optical signals sequentially passing through the polarizer and the third polarizer in the hollow shafts, and then convert the optical signals into electric signals. That is to say, the first photoelectric sensor collects the optical signals of the light source after passing through the first polarizer and the third polarizer, and the second photoelectric sensor collects the optical signals of the light source after passing through the second polarizer and the third polarizer, and then converts the two collected optical signals into electrical signals respectively.
The signal processing device is respectively connected with the first photoelectric sensor and the second photoelectric sensor and used for acquiring electric signals output by the two photoelectric sensors and analyzing the electric signals to obtain the rotation angle of the rotating piece to be detected.
When the rotating member to be tested rotates, the driving rotating shaft is driven to synchronously rotate, the driving rotating shaft drives the two hollow shafts to rotate, so that the polaroids fixed in the two hollow shafts rotate, the third polaroid is fixed, the included angle between the polaroids in the two hollow shafts and the polarization direction of the third polaroid continuously changes, and in the process, the light source continuously irradiates, so that the voltage signals collected by the two photoelectric sensors also periodically change. The rotation angle of the rotating member to be measured can be obtained by analyzing the two periodically changed voltage signals.
As shown in fig. 4 (the dotted line in the figure indicates the polarization direction), assuming that the horizontal rightward direction is at an angle of 0 ° and the counterclockwise direction is a positive direction, the polarization direction of the first polarizer a is 45 ° (i.e., 225 °), the polarization direction of the second polarizer b is 0 ° (i.e., 180 °), and the polarization direction of the third polarizer o is 0 ° (i.e., 180 °), in the initial state. At this time, assuming that the active rotating shaft rotates counterclockwise by one turn, the two hollow shafts rotate clockwise by half a turn, and the voltage signals output by the two photoelectric sensors are as shown in fig. 5 (the axis of abscissa indicates the rotation angle of the active rotating shaft, and the highest voltage value and the lowest voltage value depend on the intensity of the light emitted by the light source). It can be seen that the waveforms of the two voltage signals are in accordance with the shape of the waveform of the sinusoidal function, and that the two waveforms are offset by 90 °.
After the voltage signal diagram shown in fig. 5 is obtained, the waveforms of the two voltage signals are respectively shifted down by a distance determined according to the maximum value and the minimum value of the voltage signals. Specifically, as shown in the following formula:
Va＝V1-(Vmax+Vmin)/2；
Vb＝V2-(Vmax+Vmin)/2；
wherein, V1A voltage signal value, V, output by the first photoelectric sensor2The voltage signal value output by the second photoelectric sensor is Vmax is the highest voltage value, and Vmin is the lowest voltage value. In this embodiment, Vmax is 3V, and Vmin is 1V.
The voltage signal processed according to the above formula is shown in fig. 6. In this case, as can be seen from fig. 6, a waveform corresponding to Va is a waveform corresponding to sin θ, and a waveform corresponding to Vb is a waveform corresponding to cos θ, that is, Va is sin θ, Vb is cos θ, Va/Vb is sin θ/cos θ is tan θ, and it is derived that:
θ＝arctan(Va/Vb)。
that is, according to the two voltage signal values Va and Vb at the same time point, the angle θ of the active rotating shaft relative to the 0 ° angle at the time point can be calculatedi。
Then, the rotation angle of the active rotating shaft, namely the rotation angle of the rotating piece to be measured can be calculated by collecting the angle before the rotation starts and the angle after the rotation, so that the measurement of the rotation angle within the positive and negative 360 degrees is realized.
Example two
In the first embodiment, accurate measurement of the rotation angle within plus and minus 360 ° can be achieved only according to the θ values before and after rotation, and the first embodiment provides an angle calculation method based on the angle measurement device in the first embodiment, which can achieve measurement of any rotation angle. The method comprises the following steps:
s1: and calibrating to obtain the highest voltage value and the lowest voltage value according to the voltage signals output by the first photoelectric sensor and the second photoelectric sensor.
Further, since the light source is gradually attenuated, the highest voltage value and the lowest voltage value are changed, which results in calculation errors, so that calibration periods can be preset, and each calibration period analyzes the voltage signals output by the two photoelectric sensors again, so as to calibrate new highest voltage values and new lowest voltage values.
S2: and acquiring voltage signals of the first photoelectric sensor and the second photoelectric sensor according to a preset calculation period to obtain a first voltage value and a second voltage value. Preferably, the calculation period is 60 μ s.
S3: according to a first voltage value V corresponding to a calculation period1And a second voltage value V2And calculating the angle corresponding to the calculation period by using the maximum voltage value Vmax and the minimum voltage value Vmin.
In particular, θiArctan (Va/Vb), wherein Va is V1-(Vmax+Vmin)/2，Vb＝V2-(Vmax+Vmin)/2。
S4: and calculating the rotation angle corresponding to the calculation period according to the calculation period and the angle corresponding to the previous calculation period.
Specifically, the difference between the angle corresponding to the calculation period and the angle corresponding to the previous calculation period, i.e., Δ θ, is calculatedi＝θi-θi-1Wherein, theta-1Can be regarded as the angle detected before the rotation of the rotating member to be measured.
When the rotating member to be measured rotates forward (i.e. rotates along the forward direction), if delta thetaiIf < -K °, let Δ θi＝Δθi+360 °; when the rotating member to be measured rotates reversely (i.e. rotates in the opposite direction), if Δ θiIf > K DEG, let Delta thetai＝Δθi-360 °. Wherein, the value of K can be determined according to the calculation period. Preferably, K ═ 4.
Finally, will delta thetaiAs the rotation angle corresponding to the calculation cycle.
S5: and calculating the rotation angle of the rotating member to be measured according to the rotation angle corresponding to each calculation period from the time before the rotating member to be measured rotates to the time after the rotating member rotates.
Specifically, the rotation angles corresponding to each calculation period in the period from before to after each rotation are accumulated, so that the rotation angle of the rotating member to be measured can be obtained. For example, it can be according to formula Ai＝Ai-1+ΔθiAccumulating, i is 1,2, …, N is the total number of calculation cycles of the rotating member to be measured in the period from before rotation to after rotation, A0＝0。
In the embodiment, the whole rotation period is divided into a plurality of small calculation periods, and the rotation angles in the calculation periods are calculated respectively and then accumulated, so that the total rotation angle can be obtained.
To sum up, the utility model provides a pair of angle measurement device based on rotatory polaroid can realize rotation angle's measurement, and can guarantee measuring result's accuracy.
The above mentioned is only the embodiment of the present invention, and not the limitation of the patent scope of the present invention, all the equivalent transformations made by the contents of the specification and the drawings, or the direct or indirect application in the related technical field, are included in the patent protection scope of the present invention.
Claims (5)
1. An angle measuring device based on a rotary polaroid is characterized by comprising an active rotating shaft, a first hollow shaft, a second hollow shaft, a first polaroid, a second polaroid, a third polaroid, a light source, a first photoelectric sensor, a second photoelectric sensor and a signal processing device;
the first hollow shaft and the second hollow shaft are respectively in transmission connection with the driving rotating shaft, and the transmission ratio is 2; the first polaroid and the second polaroid are respectively arranged in the first hollow shaft and the second hollow shaft in a one-to-one correspondence manner and are positioned on the same radial plane; the included angle of the polarization directions of the first polarizer and the second polarizer is 45 degrees;
one end of the driving rotating shaft is connected with the rotating piece to be detected; the light source is positioned at one end of the driving rotating shaft and uniformly irradiates the first polaroid and the second polaroid; the third polaroid is positioned at the other end of the active rotating shaft and is parallel to the first polaroid and the second polaroid; the projection of the third polaroid on the same radial plane covers the active rotating shaft, the first hollow shaft and the second hollow shaft;
the first photoelectric sensor and the second photoelectric sensor are respectively arranged on one surface of the third polaroid, which is far away from the light source, and respectively correspond to the first hollow shaft and the second hollow shaft one by one; the signal processing device is respectively connected with the first photoelectric sensor and the second photoelectric sensor.
2. The rotary polarizer-based angle measuring device of claim 1, wherein a first gear is disposed on an outer surface of the driving shaft, a second gear is disposed on an outer surface of each of the first hollow shaft and the second hollow shaft, and the first gear and the second gear are in transmission connection; the ratio of the number of teeth of the second gear to the number of teeth of the first gear is 2.
3. The rotary polarizer-based angle measuring device of claim 1, wherein the first and second photoelectric sensors are located on an extension of a central axis of the first and second hollow shafts, respectively.
4. The rotary polarizer-based angle measuring device of claim 1, wherein an angle between an azimuth angle of the first hollow shaft and the second hollow shaft with respect to the active rotation shaft is 90 °.
5. The rotary polarizer-based angle measuring device of any one of claims 1 to 4, wherein the signal processing device is an oscilloscope or an oscillograph tracker.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120803137.6U CN215177589U (en) | 2021-04-19 | 2021-04-19 | Angle measuring device based on rotary polaroid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120803137.6U CN215177589U (en) | 2021-04-19 | 2021-04-19 | Angle measuring device based on rotary polaroid |
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| CN215177589U true CN215177589U (en) | 2021-12-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202120803137.6U Expired - Fee Related CN215177589U (en) | 2021-04-19 | 2021-04-19 | Angle measuring device based on rotary polaroid |
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- 2021-04-19 CN CN202120803137.6U patent/CN215177589U/en not_active Expired - Fee Related
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Granted publication date: 20211214 |