CN112835014A - Laser radar scanning holder and error elimination method thereof - Google Patents
Laser radar scanning holder and error elimination method thereof Download PDFInfo
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- CN112835014A CN112835014A CN202011609859.4A CN202011609859A CN112835014A CN 112835014 A CN112835014 A CN 112835014A CN 202011609859 A CN202011609859 A CN 202011609859A CN 112835014 A CN112835014 A CN 112835014A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/497—Means for monitoring or calibrating
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Abstract
The invention discloses a laser radar scanning holder and an error elimination method thereof, wherein the error elimination method comprises the following steps: acquiring a measured value of a first encoder which is coaxially arranged with a motor shaft and a measured value of a second encoder which is arranged on an output shaft of a speed reducer; determining an accumulated error caused by a clearance of the decelerator and a pulse spur of the first encoder according to a difference between the measurement value of the first encoder and the measurement value of the second encoder; and compensating the measurement scanning angle of the holder according to the accumulated error so as to obtain the actual scanning angle of the holder, wherein the rotation angle of the motor shaft is divided by the reduction ratio of the speed reducer to be the measurement scanning angle of the holder. According to the invention, the accumulated error can be compensated online, the angle precision and stability of the scanning system are improved, the scanning efficiency is improved, and the dynamic performance of the scanning system is improved.
Description
Technical Field
The invention belongs to the field of laser radars, and particularly relates to a laser radar scanning holder and an error elimination method thereof.
Background
At present, most of laser radar scanning holders are realized by adopting a scheme of matching a two-dimensional laser radar with a one-dimensional scanning holder. In the laser radar scanning cloud platform, the drive scheme can adopt a direct drive scheme or a speed reducer drive scheme, and in the direct drive scheme, because no speed reducer exists, no transmission gap exists, but the output torque of the motor needs to be increased, and the size of the motor needs to be increased, so that the volume and the weight of the scanning system are increased. In order to reduce the volume and the weight of a scanning tripod head, a scheme of a servo motor speed reducer can be adopted, the output torque is improved, but a gap exists in a speed reducer, the gap can change along with the increase of the service time, the scanning precision is influenced, in order to improve the dynamic characteristic of the tripod head, an incremental encoder is used as a tripod head measuring angle sensor, but the incremental encoder runs for a long time and has errors caused by burrs, in order to compensate the errors caused by the gap and the burrs, a datum point needs to be returned for calibration after the end of single scanning, and the scanning efficiency is greatly reduced.
In view of the above, overcoming the drawbacks of the prior art is an urgent problem in the art.
Disclosure of Invention
Aiming at the defects or the improvement requirements of the prior art, the invention provides a laser radar scanning holder and an error elimination method thereof, aiming at realizing online compensation of accumulated errors, improving the stability of the scanning holder, improving the scanning efficiency and improving the dynamic performance of the scanning holder, thereby solving the technical problems of low scanning efficiency, large volume and poor dynamic performance of the traditional scanning holder.
To achieve the above object, according to an aspect of the present invention, there is provided an error elimination method for a laser radar scanning pan-tilt, including:
acquiring a measurement value of a first encoder 41 disposed coaxially with the motor shaft 11 and a measurement value of a second encoder 42 mounted on the output shaft 21 of the speed reducer 2;
determining the cumulative error due to the backlash of the retarder 2 and the pulse spikes of the first encoder 41 from the difference between the measurement of the first encoder 41 and the measurement of the second encoder 42;
and compensating the measurement scanning angle of the holder according to the accumulated error so as to obtain the actual scanning angle of the holder, wherein the rotating angle of the motor shaft 11 is divided by the reduction ratio of the speed reducer 2 to be the measurement scanning angle of the holder.
Preferably, said determining the accumulated error due to the backlash of the retarder 2 and to the pulse spikes of the first encoder 41 as a function of the difference between the measurement of the first encoder 41 and the measurement of the second encoder 42 comprises:
performing difference processing on the measurement value of the first encoder 41 and the measurement value of the second encoder 42, and acquiring an absolute value of the difference to acquire an error angle between the first encoder 41 and the second encoder 42 at the current time;
filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle;
and judging whether the change rate Detaf is within a set threshold value, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f.
Preferably, said determining the accumulated error due to the backlash of the retarder 2 from the difference between the measurements of the first encoder 41 and the second encoder 42 further comprises, before:
receiving a set scanning range of the holder, and determining the running scanning range of the holder according to the set scanning range and the accumulated error;
judging whether the motor 1 runs to the lowest point or not according to the running scanning range and the measurement value of the second encoder 42;
if the motor 1 runs to the lowest point, it is judged whether the speed of the motor 1 is greater than 0, and if the speed of the motor 1 is greater than 0, the step of determining the accumulated error caused by the backlash of the decelerator 2 and the pulse burr of the first encoder 41 according to the difference between the measurement value of the first encoder 41 and the measurement value of the second encoder 42 is performed.
Preferably, the compensating the measured scanning angle of the pan/tilt head according to the accumulated error, and further obtaining the actual scanning angle of the pan/tilt head includes:
when the scanning is carried out in the forward direction, subtracting the accumulated error from the measured scanning angle to obtain the actual scanning angle;
when scanning in the negative direction, the measurement scanning angle is equal to the actual scanning angle.
Preferably, the first encoder 41 is an incremental encoder, and the second encoder 42 is an absolute encoder.
According to another aspect of the present invention, there is provided a lidar scanning head comprising: the motor 1, the speed reducer 2, the driver 3, the first encoder 41 and the second encoder 42;
the motor 1 is installed at the input end of the speed reducer 2 through a motor shaft 11, the first encoder 41 is coaxially arranged with the motor shaft 11, the second encoder 42 is installed on the output shaft 21 of the speed reducer 2, and the driver 3 is connected with the first encoder 41 and the second encoder 42;
the first encoder 41 is configured to measure a rotation angle of the motor shaft 11, and the second encoder 42 is configured to measure a rotation angle of the output shaft 21, where the rotation angle of the motor shaft 11 divided by the reduction ratio of the speed reducer 2 is a measurement scanning angle of the pan/tilt head;
the driver 3 is configured to determine an accumulated error caused by the gap of the decelerator 2 and the pulse glitch of the first encoder 41 according to a difference between the measurement value of the first encoder 41 and the measurement value of the second encoder 42, so as to compensate the measured scan angle according to the accumulated error, thereby obtaining an actual scan angle of the pan/tilt head.
Preferably, the driver 3 is specifically configured to perform difference processing on the measurement value of the first encoder 41 and the measurement value of the second encoder 42, and obtain an absolute value of the difference, so as to obtain an error angle between the first encoder 41 and the second encoder 42 at the current time;
filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle;
judging whether the change rate Detaf is within a set threshold value, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f;
and compensating the measurement scanning angle according to the accumulated error so as to obtain the actual scanning angle of the holder.
Preferably, when scanning in the forward direction, the driver 3 is configured to subtract the accumulated error from the measured scan angle to obtain the actual scan angle;
the driver 3 is arranged to set the actual scan angle equal to the measured scan angle when scanning in the negative direction.
Preferably, the first encoder 41 is an incremental encoder, and the second encoder 42 is an absolute encoder.
Preferably, the lidar scanning platform further comprises a first bracket 5 and a second bracket 6, and the motor 1 and the speed reducer 2 are mounted on the first bracket 5;
an output shaft 21 of the speed reducer 2 is fixed on the first bracket 5 through a bearing 7;
the second bracket 6 is provided with a photoelectric switch 81, and the output shaft 21 of the speed reducer 2 is provided with a laser radar 9 and a limiting slide block 82.
Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects: the invention provides a laser radar scanning holder and an error elimination method thereof, wherein the error elimination method comprises the following steps: acquiring a measured value of a first encoder which is coaxially arranged with a motor shaft and a measured value of a second encoder which is arranged on an output shaft of a speed reducer; determining an accumulated error caused by a clearance of the decelerator and a pulse spur of the first encoder according to a difference between the measurement value of the first encoder and the measurement value of the second encoder; and compensating the measurement scanning angle of the holder according to the accumulated error so as to obtain the actual scanning angle of the holder, wherein the rotation angle of the motor shaft is divided by the reduction ratio of the speed reducer to be the measurement scanning angle of the holder.
According to the invention, the accumulated error can be compensated online, the angle precision and stability of the scanning system are improved, the scanning efficiency is improved, and the dynamic performance of the scanning system is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings described below are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.
Fig. 1 is a schematic structural diagram of a laser radar scanning pan-tilt provided by an embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating a relationship between a set scanning range and an operating scanning range according to an embodiment of the present invention;
FIG. 3a is a schematic diagram illustrating an analysis of accumulated error due to gear lash provided by an embodiment of the present invention;
FIG. 3b is a schematic diagram illustrating an analysis of accumulated error due to encoder pulse glitches according to an embodiment of the present invention;
fig. 4 is a schematic flow chart of an error elimination method for a laser radar scanning pan-tilt according to an embodiment of the present invention;
fig. 5 is a schematic flow chart of another method for eliminating an error of a laser radar scanning pan/tilt head according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Example 1:
referring to fig. 1, the present embodiment provides a laser radar scanning pan/tilt head, which includes: the motor 1, the speed reducer 2, the driver 3, the first encoder 41 and the second encoder 42;
the motor 1 is installed at the input end of the speed reducer 2 through a motor shaft 11, the first encoder 41 is coaxially arranged with the motor shaft 11, the second encoder 42 is installed on the output shaft 21 of the speed reducer 2, and the driver 3 is connected with the first encoder 41 and the second encoder 42;
the first encoder 41 is configured to measure a rotation angle of the motor shaft 11, and the second encoder 42 is configured to measure a rotation angle of the output shaft 21, where the rotation angle of the motor shaft 11 divided by the reduction ratio of the speed reducer 2 is a measurement scanning angle of the pan/tilt head;
the driver 3 is configured to determine an accumulated error caused by the gap of the decelerator 2 and the pulse glitch of the first encoder 41 according to a difference between the measurement value of the first encoder 41 and the measurement value of the second encoder 42, so as to compensate the measured scan angle according to the accumulated error, thereby obtaining an actual scan angle of the pan/tilt head.
In an alternative embodiment, the first encoder 41 is an incremental encoder and the second encoder 42 is an absolute encoder.
In an actual application scene, the laser radar scanning holder further comprises a first support 5 and a second support 6, and the motor 1 and the speed reducer 2 are mounted on the first support 5; an output shaft 21 of the speed reducer 2 is fixed on the first bracket 5 through a bearing 7; the second bracket 6 is provided with a photoelectric switch 81, the output shaft 21 of the speed reducer 2 is provided with a laser radar 9 and a limiting slide block 82, and the photoelectric switch 81 and the limiting slide block 82 are mutually matched to play a role in limiting protection.
Further, the driver 3 is further configured to drive the motor 1 to rotate, so as to drive the output shaft 21 of the speed reducer 2 to rotate, thereby implementing the pitching scanning of the pan/tilt head.
Taking the cloud platform coordinate system set in the upper left corner of fig. 1 as an example, the XOZ plane is the scanning plane of the laser radar 9, the YOX plane is the scanning plane of the cloud platform, and in order to reduce the synchronous error between the cloud platform scanning angle and the laser radar 9 scanning angle, the dynamic characteristic of the scanning cloud platform is high, and the angle acquisition speed is as fast as possible. In the speed reducer scheme of the prior art, because the speed reducer 2 has a gap, the gap can change along with the increase of the service time, the scanning precision is influenced, in order to improve the dynamic characteristic of the holder, an incremental encoder is used as a holder measuring angle sensor, but the incremental encoder runs for a long time and has errors caused by pulse burrs, in order to compensate accumulated errors caused by the gap and the pulse burrs, a reference point needs to be calibrated once after the single scanning is finished, and the scanning efficiency is greatly reduced. In order to solve this problem, in the present embodiment, the incremental encoder (the first encoder 41) is calibrated by using the absolute encoder (the second encoder 42), so as to eliminate the accumulated error, improve the dynamic performance of the scanning platform by using the high bandwidth characteristic of the incremental encoder, and reduce the synchronization error.
The process of eliminating the accumulated error is described in detail below: in an actual application scenario, the operation scanning range b corresponding to the pan/tilt head is greater than the set scanning angle range a, as shown in fig. 2, a relationship between the set scanning angle range a and the operation scanning range b is shown, where the operation scanning range b is greater than the set scanning angle range a, and in an alternative embodiment, b is a + accumulated error +2 degrees (or other values, which are not specifically limited herein). In this embodiment, the upward scanning is an angle increasing direction, which is hereinafter referred to as a positive scanning, and the downward scanning is an angle decreasing direction, which is hereinafter referred to as a negative scanning. The first encoder 41 is an incremental encoder and the second encoder 42 is an absolute encoder. Assuming that the measured value of the incremental encoder is c and the true value of the incremental encoder angle is d, where the true value of the angle refers to the value after the accumulated error is eliminated, and the accumulated error is e, the relationship is as follows: in forward scanning, d is c/reduction ratio-e of the reducer 2; in the negative direction, d is c/reduction ratio of the reduction gear 2.
When the lower limit of the scanning motion of fig. 2 is reached, the scanning motion is reversed, and in this process, the driver 3 is specifically configured to perform difference processing on the measurement value of the first encoder 41 and the measurement value of the second encoder 42, and obtain an absolute value of the difference, so as to obtain an error angle between the first encoder 41 and the second encoder 42 at the current time; filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle; judging whether the change rate Detaf is within a set threshold value, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f; and compensating the measurement scanning angle according to the accumulated error so as to obtain the actual scanning angle of the holder.
The specific compensation mode is as follows: when the scanning is carried out in the forward direction, subtracting the accumulated error from the measured scanning angle to obtain the actual scanning angle; the driver 3 is adapted to set the measured scan angle equal to the actual scan angle when scanning in the negative direction.
The kalman filter equation is as follows: xk/k-1=AXk-1/k-1+Buk-1;Pk/k-1=APk-1/k-1AT+Q;Xk/k=Xk/k-1+Kk(Zk-Xk/k-1);Pk/k=(I-KkH)Pk/k-1(ii) a Wherein A represents a state transition matrix, B represents an input matrix, H represents an observation matrix, and Q represents a system variance; r represents the measurement variance, and Xk-1/k-1 represents the optimal value at the last moment; xk/k-1 represents the current timePredicting a value; xk/k represents the optimal value at the current moment; pk-1/k-1 represents the optimal estimation variance at the last moment; pk/k-1 represents the prediction variance at the current moment; pk/k represents the optimal variance at the current moment; kk represents the Kalman gain; zk represents the measured value; i denotes an identity matrix. Here, it should be noted that, in this embodiment, only the kalman filter equation is briefly shown, and the actual filtering process of the kalman filter may be implemented by referring to the prior art, which is not described herein again.
The foregoing principle of determining the accumulated error is described below in conjunction with fig. 3 a: in fig. 3, there is a gap between the gear B and the gear C, a being a gear corresponding to the output shaft 21 of the decelerator 2, and B and C being gears corresponding to the motor shaft 11, assuming that the motor 1 runs to the lowest point, a is at B, after the reverse movement, a is not moving, C is moving towards a, at which time, since a is not moving, the value of the second encoder 42 (absolute encoder) is not changed, and C is moving, the value of the first encoder 41 is increasing, the rate of change of the error angle Detaf of the first encoder 41 and the second encoder 42 is changing, when a and C touch, a and C move in opposite directions together, and the error angle of the first encoder 41 and the second encoder 42 is the largest, and is maintained constant in this scan, the rate of change Detaf of the error angle of the first encoder 41 and the second encoder 42 is maintained at a constant value, and at this time, the accumulated error is equal to the angular error corresponding to the rate of change Detaf maintaining a constant value.
Furthermore, when the first encoder 41 has a pulse glitch as shown in fig. 3b, an accumulated error is also caused.
In this embodiment, each scanning can obtain current accumulative error, realize accumulative error's dynamic compensation, utilize incremental encoder's high bandwidth characteristic simultaneously, can acquire scanning angle value fast, improve the synchronous precision of scanning cloud platform angle and radar scanning angle.
Example 2:
referring to fig. 4, based on the laser radar scanning pan/tilt head of embodiment 1, this embodiment provides an error elimination method for a laser radar scanning pan/tilt head, which specifically includes the following steps:
step 101: the measurement value of the first encoder 41 disposed coaxially with the motor shaft 11 and the measurement value of the second encoder 42 mounted on the output shaft 21 of the speed reducer 2 are acquired.
The first encoder 41 is an incremental encoder, and the second encoder 42 is an absolute encoder.
With reference to fig. 5, in an actual application scenario, during initial use, a scanning angle range a of the pan/tilt head is set on the upper computer, and an initial accumulated error e is equal to 0, so that according to the formula of embodiment 1, an actual operating scanning range b of the pan/tilt head is equal to a + e +2 degrees, thereby ensuring that the pan/tilt head scans according to a set path.
Specifically, a set scanning range of the pan/tilt head is received, and an operating scanning range of the pan/tilt head is determined according to the set scanning range and an accumulated error, wherein in the first scanning cycle, the accumulated error is initialized to 0.
And judging whether the motor 1 runs to the lowest point or not according to the running scanning range and the measurement value of the second encoder 42, specifically, determining the scanning angle of the pan-tilt head according to the measurement value of the second encoder 42, judging whether the scanning angle is equal to the lower limit value of the running scanning range or not, and if the scanning angle is equal to the lower limit value of the running scanning range, running the motor 1 to the lowest point.
If the motor 1 runs to the lowest point, whether the speed of the motor 1 is greater than 0 is judged, and if the speed of the motor 1 is greater than 0, step 102 is executed. If the motor 1 does not run to the lowest point, the scan continues.
Step 102: the cumulative error caused by the play of the retarder 2 and the pulse glitch of the first encoder 41 is determined from the difference between the measurement of the first encoder 41 and the measurement of the second encoder 42.
Specifically, the measurement value of the first encoder 41 and the measurement value of the second encoder 42 are subjected to difference processing, and an absolute value of the difference is obtained, so as to obtain an error angle between the first encoder 41 and the second encoder 42 at the current time;
filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle; and judging whether the change rate Detaf is within a set threshold value, wherein the set threshold value can be-0.2, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f. And if the error angle is not within the set threshold, continuously acquiring the error angle between the first encoder 41 and the second encoder 42 at the next moment, and sending the error angle to a second-order Kalman filter for filtering.
Step 103: and compensating the measurement scanning angle of the holder according to the accumulated error so as to obtain the actual scanning angle of the holder, wherein the rotating angle of the motor shaft 11 is divided by the reduction ratio of the speed reducer 2 to be the measurement scanning angle of the holder.
Specifically, when scanning in the forward direction, subtracting the accumulated error from the measured scanning angle to obtain the actual scanning angle; when scanning in the negative direction, the measurement scanning angle is equal to the actual scanning angle.
In this embodiment, each scanning can obtain current accumulative error, realize accumulative error's dynamic compensation, utilize incremental encoder's high bandwidth characteristic simultaneously, can acquire scanning angle value fast, improve the synchronous precision of scanning cloud platform angle and radar scanning angle.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. An error elimination method for a laser radar scanning pan-tilt is characterized by comprising the following steps:
acquiring a measurement value of a first encoder (41) arranged coaxially with the motor shaft (11) and a measurement value of a second encoder (42) mounted on the output shaft (21) of the reducer (2);
determining the cumulative error caused by the backlash of the retarder (2) and the pulse glitch of the first encoder (41) from the difference between the measurement of the first encoder (41) and the measurement of the second encoder (42);
and compensating the measurement scanning angle of the holder according to the accumulated error so as to obtain the actual scanning angle of the holder, wherein the rotating angle of the motor shaft (11) is divided by the reduction ratio of the speed reducer (2) to be the measurement scanning angle of the holder.
2. The error cancellation method according to claim 1, wherein the determining of the accumulated error caused by the backlash of the retarder (2) and the pulse glitch of the first encoder (41) from the difference between the measurement of the first encoder (41) and the measurement of the second encoder (42) comprises:
performing difference processing on the measurement value of the first encoder (41) and the measurement value of the second encoder (42), and acquiring an absolute value of the difference to acquire an error angle between the first encoder (41) and the second encoder (42) at the current moment;
filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle;
and judging whether the change rate Detaf is within a set threshold value, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f.
3. The error concealment method according to claim 1, wherein the determining of the accumulated error caused by the backlash of the retarder (2) and the pulse glitch of the first encoder (41) from the difference between the measurement of the first encoder (41) and the measurement of the second encoder (42) is preceded by:
receiving a set scanning range of the holder, and determining the running scanning range of the holder according to the set scanning range and the accumulated error;
judging whether the motor (1) runs to the lowest point or not according to the running scanning range and the measured value of the second encoder (42);
if the motor (1) runs to the lowest point, it is judged whether the speed of the motor (1) is greater than 0, and if the speed of the motor (1) is greater than 0, the step of determining an accumulated error caused by the backlash of the decelerator (2) and the pulse glitch of the first encoder (41) according to the difference between the measurement value of the first encoder (41) and the measurement value of the second encoder (42) is performed.
4. The method of claim 1, wherein the compensating the measured scan angle of the pan/tilt head according to the accumulated error to obtain the actual scan angle of the pan/tilt head comprises:
when the scanning is carried out in the forward direction, subtracting the accumulated error from the measured scanning angle to obtain the actual scanning angle;
when scanning in the negative direction, the measurement scanning angle is equal to the actual scanning angle.
5. The error cancellation method according to claim 1, characterized in that the first encoder (41) is an incremental encoder and the second encoder (42) is an absolute encoder.
6. The utility model provides a laser radar scanning cloud platform which characterized in that, laser radar scanning cloud platform includes: the device comprises a motor (1), a speed reducer (2), a driver (3), a first encoder (41) and a second encoder (42);
the motor (1) is installed at the input end of the speed reducer (2) through a motor shaft (11), the first encoder (41) and the motor shaft (11) are coaxially arranged, the second encoder (42) is installed on an output shaft (21) of the speed reducer (2), and the driver (3) is connected with the first encoder (41) and the second encoder (42);
the first encoder (41) is used for measuring the rotation angle of the motor shaft (11), the second encoder (42) is used for measuring the rotation angle of the output shaft (21), and the rotation angle of the motor shaft (11) divided by the reduction ratio of the speed reducer (2) is the measurement scanning angle of the tripod head;
the driver (3) is used for determining accumulated errors caused by the clearance of the speed reducer (2) and pulse burrs of the first encoder (41) according to the difference value between the measurement value of the first encoder (41) and the measurement value of the second encoder (42), so as to compensate the measured scanning angle according to the accumulated errors, and further obtain the actual scanning angle of the tripod head.
7. Lidar scanning head according to claim 6, wherein said driver (3) is specifically configured to perform a difference processing on the measurement value of said first encoder (41) and the measurement value of said second encoder (42), and obtain an absolute value of the difference to obtain an error angle between said first encoder (41) and said second encoder (42) at the current time;
filtering the error angle through a second-order Kalman filter to obtain the change rate Detaf of the error angle;
judging whether the change rate Detaf is within a set threshold value, if so, acquiring an error angle f corresponding to the change rate Detaf equal to a set value, and setting the accumulated error equal to the error angle f;
and compensating the measurement scanning angle according to the accumulated error so as to obtain the actual scanning angle of the holder.
8. Lidar scanning head according to claim 6, wherein said driver (3) is adapted to subtract said accumulated error from said measured scan angle to said actual scan angle when scanning in forward direction;
the driver (3) is adapted to set the actual scan angle equal to the measured scan angle when scanning in the negative direction.
9. Lidar scanning head according to claim 6, wherein said first encoder (41) is an incremental encoder and said second encoder (42) is an absolute encoder.
10. A lidar scanning head according to claim 6, characterized in that it further comprises a first bracket (5) and a second bracket (6), said motor (1) and said reducer (2) being mounted on said first bracket (5);
an output shaft (21) of the speed reducer (2) is fixed on the first bracket (5) through a bearing (7);
the photoelectric switch (81) is arranged on the second support (6), and the laser radar (9) and the limiting sliding block (82) are arranged on the output shaft (21) of the speed reducer (2).
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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CN114199282A (en) * | 2022-02-17 | 2022-03-18 | 南京谷贝电气科技有限公司 | Angle sensor calibration device and method based on double encoders |
CN117214875A (en) * | 2023-11-08 | 2023-12-12 | 山东富锐光学科技有限公司 | Zero point calibration method and structure for laser radar incremental coding |
CN118034174A (en) * | 2024-04-15 | 2024-05-14 | 南京比沃特视频***有限公司 | Data processing method and device for double encoder system |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL7703324A (en) * | 1976-11-15 | 1978-05-17 | Marconi Co Ltd | REGULATION FOR STABILIZATION. |
CN102854891A (en) * | 2012-09-18 | 2013-01-02 | 天津市亚安科技股份有限公司 | Stability control device and method based on direct drive of torque motor |
CN105571578A (en) * | 2015-12-14 | 2016-05-11 | 武汉大学 | In-situ rotating modulating north-seeking method utilizing pseudo-observation instead of precise turntable |
CN106525074A (en) * | 2016-10-13 | 2017-03-22 | 重庆零度智控智能科技有限公司 | Compensation method and device for holder drift, holder and unmanned aerial vehicle |
CN109250004A (en) * | 2018-10-29 | 2019-01-22 | 逻腾(杭州)科技有限公司 | A kind of panoramic information acquisition rolling robot |
CN110187721A (en) * | 2019-05-05 | 2019-08-30 | 湖北久之洋红外***股份有限公司 | One kind thousand indexes accurate holder motion control device and method |
US20190310355A1 (en) * | 2019-06-12 | 2019-10-10 | Intel Corporation | Light detection and ranging (lidar) scanners for mobile platforms |
CN210950492U (en) * | 2019-09-27 | 2020-07-07 | 上海道简机电科技有限公司 | High-precision integrated laser scanning holder |
CN111721289A (en) * | 2020-06-28 | 2020-09-29 | 北京百度网讯科技有限公司 | Vehicle positioning method, device, equipment, storage medium and vehicle |
-
2020
- 2020-12-30 CN CN202011609859.4A patent/CN112835014A/en active Pending
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL7703324A (en) * | 1976-11-15 | 1978-05-17 | Marconi Co Ltd | REGULATION FOR STABILIZATION. |
CN102854891A (en) * | 2012-09-18 | 2013-01-02 | 天津市亚安科技股份有限公司 | Stability control device and method based on direct drive of torque motor |
CN105571578A (en) * | 2015-12-14 | 2016-05-11 | 武汉大学 | In-situ rotating modulating north-seeking method utilizing pseudo-observation instead of precise turntable |
CN106525074A (en) * | 2016-10-13 | 2017-03-22 | 重庆零度智控智能科技有限公司 | Compensation method and device for holder drift, holder and unmanned aerial vehicle |
CN109250004A (en) * | 2018-10-29 | 2019-01-22 | 逻腾(杭州)科技有限公司 | A kind of panoramic information acquisition rolling robot |
CN110187721A (en) * | 2019-05-05 | 2019-08-30 | 湖北久之洋红外***股份有限公司 | One kind thousand indexes accurate holder motion control device and method |
US20190310355A1 (en) * | 2019-06-12 | 2019-10-10 | Intel Corporation | Light detection and ranging (lidar) scanners for mobile platforms |
CN210950492U (en) * | 2019-09-27 | 2020-07-07 | 上海道简机电科技有限公司 | High-precision integrated laser scanning holder |
CN111721289A (en) * | 2020-06-28 | 2020-09-29 | 北京百度网讯科技有限公司 | Vehicle positioning method, device, equipment, storage medium and vehicle |
Non-Patent Citations (3)
Title |
---|
唐昌银: "伺服云台结构设计", 《现代制造技术与装备》 * |
张立勋 等: "《机电一体化***设计》", 31 March 2014 * |
赵松年 等: "《机电一体化机械***设计》", 30 June 1996, 机械工业出版社 * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114199282A (en) * | 2022-02-17 | 2022-03-18 | 南京谷贝电气科技有限公司 | Angle sensor calibration device and method based on double encoders |
CN114199282B (en) * | 2022-02-17 | 2022-05-10 | 南京谷贝电气科技有限公司 | Angle sensor calibration device and method based on double encoders |
CN117214875A (en) * | 2023-11-08 | 2023-12-12 | 山东富锐光学科技有限公司 | Zero point calibration method and structure for laser radar incremental coding |
CN118034174A (en) * | 2024-04-15 | 2024-05-14 | 南京比沃特视频***有限公司 | Data processing method and device for double encoder system |
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