JP2017116512A - Three-dimensional scanning device and three-dimensional positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional scanning device that is highly general and can suppress continuous generations of dead angles to reduce influence of the dead angles on an equipped system, the device realizing a track of scanning a three-dimensional space without requiring control on the rotational direction of a power unit by a single power unit with the fixed rotational direction.SOLUTION: A rotational plate 405 is rotated by a rotational power transmitted from a power unit 402 to a gear P404, and the rotational power is conveyed to a front surface cam 409 via gears B509, C406, and D407. The rotational power is converted into a reciprocating linear motion of a slide plate 410 by the front surface cam 409, and scanning of a three-dimensional space is realized by a reciprocating rotating motion of an arm 414, connected to a rack 411 via a gear E413.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an apparatus for scanning a three-dimensional space.

  The three-dimensional recognition of the external environment is applied to the discovery of intruders in security systems, the recognition of pedestrians in automobiles, the detection of obstacles in robots, etc., and has become an important technology in various systems. However, since the sensor used for recognition has a measurement range limit, information obtained from a single sensor is limited. As a means for solving this problem and recognizing a three-dimensional space by a single sensor, a method of scanning the three-dimensional space by adding some movable mechanism driven by a power unit to the sensor has been proposed.

  In particular, a mechanism that does not depend on the characteristics of the sensor and that is operated by a single power unit can be added to any sensor, so it is highly versatile. And cost reduction can be expected.

  One example of a mechanism having the above characteristics is a mechanism proposed in Patent Document 1. A three-dimensional space scan by a spiral trajectory is realized by a flange that moves while rotating around the axis of the stud bolt and a link mechanism that follows the flange.

  Another example of the mechanism having the same characteristics is the mechanism proposed in Patent Document 2. By combining a plurality of worm gears, rotation in the pan direction and tilt direction by a single power unit is realized, and a three-dimensional space is scanned by a spiral trajectory.

JP 2013-88366 A Japanese Patent No. 5582432

  FIG. 13 shows a schematic diagram of the spiral scanning orbit L2 used in the conventional mechanism observed from the horizontal direction. In the spiral scanning trajectory, the trajectory does not intersect during one cycle of scanning, so that a continuous blind spot is generated between the trajectories. For this reason, when a three-dimensional space is recognized by a sensor using a conventional mechanism, it is predicted that a misrecognition will occur due to a characteristic part such as an edge to be recognized entering the blind spot. In order to reduce the blind spot, it is necessary to narrow the trajectory interval d2. However, since the time required for scanning increases in proportion thereto, the scanning efficiency is lowered.

In the spiral scanning trajectory, a plurality of trajectories close to the horizontal are stacked in the vertical direction to scan the three-dimensional space. Therefore, when the three-dimensional space is recognized by the sensor, the horizontal measurement interval can be adjusted by controlling the scanning speed. On the other hand, since the orbit interval d2 depends only on the structure of the mechanism and the distance from the mechanism, the measurement interval in the vertical direction cannot be adjusted by controlling the scanning speed, and the measurement in the vertical direction is performed according to the measurement environment. Use such as changing the resolution is impossible.

  In the conventional mechanism, it is necessary to change the rotation direction of the power unit in order to start the next scanning after one cycle of the three-dimensional spatial scanning is completed. When changing the direction of rotation, the system equipped with the mechanism is affected by inertia, which adversely affects the behavior of the system.

  In light of the above problems, the present invention requires a rotation direction control that provides a scanning trajectory that can fragment the blind spot and improve the measurement resolution in the vertical direction, and realize scanning of the three-dimensional space by the scanning trajectory. It is an object of the present invention to provide a three-dimensional scanning device driven by a single power device.

  The three-dimensional scanning device of the present invention realizes scanning in a three-dimensional space by combining a plurality of unit scanning trajectories (FIG. 1) obtained by simultaneously changing the rotation angles in the pan direction and the tilt direction. The unit scanning trajectory is defined as an expression shown in Equation 1. r is the distance from the center of the mechanism to the trajectory, θ is the rotation angle in the pan direction with respect to the start end of the trajectory, θp is the rotation angle in the pan direction required from the start end to the end of the trajectory, that is, the pan scanned by one unit scan trajectory. This is a scanning area in the direction. θt is the difference between the maximum angle and the minimum angle in the tilt direction, that is, the scan area in the tilt direction, and θm is the maximum angle in the tilt direction. Equation 1 shows that the scanning trajectory depends only on the pan rotation angle, which means that the unit scanning trajectory can be realized by a single power unit.

When θ is monotonously increased, the end of one unit scanning trajectory is the starting end of the next unit scanning trajectory. Therefore, if the starting end of the i-th unit scanning trajectory is P _Si and the end is P _Ei , the relationship of Equation 2 is established. In the unit scanning trajectory in which the start end does not coincide with the end, that is, in the unit scanning trajectory that satisfies the condition of Equation 3, the relationship of Equation 4 is established. Therefore, the unit scanning trajectory can be displaced by monotonically increasing θ. By integrating the displaced unit scanning trajectories, it is possible to realize three-dimensional spatial scanning by a three-dimensional mesh scanning trajectory in which a plurality of unit scanning trajectories intersect. Realization of the three-dimensional mesh scanning trajectory by monotonic increase of θ indicates that it is not necessary to control the rotational direction of the power unit.

FIG. 3 shows an appearance of a device that scans a three-dimensional space using the above-described three-dimensional mesh scanning trajectory, and FIG. 4 shows a sectional view showing the internal structure. The present invention includes a base plate at the bottom of the apparatus, a shaft A fixed perpendicular to the base plate, a rotating plate that can freely rotate around the shaft A, and a single unit that supplies rotational power. , A gear P that transmits the rotational power to the rotating plate, the rotation axis of which is fixed to the rotating plate so as to coincide with the central axis of the shaft A, and the rotating shaft that is the central axis of the shaft A The gear A is fixed to the shaft A in a manner consistent with the gear A and does not rotate by itself, the gear B meshing with the gear A and rotating circularly around the gear A according to the rotation of the rotating plate, and the central shaft The shaft B is fixed to the gear B so as to coincide with the rotation axis of the gear B, and is inserted into the hole on the rotating plate so as to freely rotate, and the rotation shaft is aligned with the central axis of the shaft B. A rotating plate fixed to the material B and meshing with the gear C on the rotating plate that rotates by itself as the gear B rotates. A gear D disposed on the support plate A, a support plate A that supports the gear C and the gear D in a sandwiched manner with the rotation plate, and a conversion mechanism disposed on the rotation plate that converts the rotational motion of the gear D into a reciprocating linear motion. The slide plate that reciprocates linearly by the converted power, the rack that is arranged in parallel with the movable range of the slide plate, and the slide plate that is connected to the slide plate via the gear E that meshes with the rack. In addition, the arm includes a reciprocating rotary motion in the tilt direction, and a support plate B to which the arm is fixed.

By driving the power unit, the rotating plate, gear B, gear C, gear D, support plate A, conversion mechanism, slide plate, rack, gear E, arm, support plate B rotate integrally in the pan direction. The generated rotational power of the gear B is transmitted to the gear C, the gear D, the conversion mechanism, the slide plate, the rack, the gear E, and the arm, and the arm performs a reciprocating rotational motion in the tilt direction. Realizes 3D spatial scanning by orbit.

  In the present invention, a three-dimensional space is scanned by a three-dimensional mesh scanning trajectory formed by a plurality of unit scanning trajectories intersecting each other. A schematic diagram of the three-dimensional mesh scanning trajectory L1 observed from the horizontal direction is shown in FIG. Compared with FIG. 13 which shows the spiral scanning trajectory used in the conventional mechanism, the blind spots are fragmented by crossing the unit scanning trajectories oblique to the horizontal. As a result, it is possible to suppress the occurrence of erroneous recognition due to the recognition target entering the blind spot.

  Compared with the conventional spiral scanning trajectory, where the vertical measurement resolution does not depend on the scanning speed, the 3D mesh scanning trajectory is composed of unit scanning trajectories that are oblique to the horizontal, so vertical measurement is possible. The resolution also depends on the scanning speed. Therefore, it can be used flexibly, for example, by reducing the scanning speed according to the situation and improving the measurement resolution in the vertical direction.

Further, the rotational direction of the power unit required for scanning the three-dimensional space is constant, and it is not necessary to change the rotational direction that accompanies generation of inertial force. That is, the adverse effect on the operation of the system by mounting the present invention in the system can be reduced.

In addition, a device that does not impair the advantages of conventional mechanisms, such as high versatility that can be added to any type of sensor, and that it can be driven by a single power unit. It has become. In addition, the provided three-dimensional scanning device can be used as a three-dimensional positioning device by adding a sensor.

FIG. 1 is a schematic diagram of unit scanning trajectories constituting a three-dimensional mesh scanning trajectory. FIG. 2 is a schematic diagram of a three-dimensional mesh scanning trajectory. FIG. 3 is an external view of the three-dimensional scanning apparatus according to the present invention. FIG. 4 is a cross-sectional view showing the internal structure of the three-dimensional scanning apparatus according to the present invention. FIG. 5 is a schematic view of a three-dimensional mesh scanning trajectory observed from the horizontal direction. FIG. 6 is a schematic diagram showing the relationship between gear A and gear B during rotation of the rotating plate. FIG. 7 is a schematic diagram showing the relationship between the gear C and the gear D. FIG. 8 is a schematic view of the front cam observed from a direction perpendicular to the grooved surface. FIG. 9 is a diagram showing the movement of Pc accompanying the rotation of the front cam. FIG. 10 is a schematic diagram showing the relationship between the slide plate and the gear E. As shown in FIG. FIG. 11 is a diagram showing a power transmission path. FIG. 12 is a diagram showing the operation of the three-dimensional spatial scanning of the present invention. FIG. 13 is a schematic view of the helical scanning trajectory observed from the horizontal direction.

  The present invention is constituted by the components shown in FIGS. A shaft member A501 is vertically arranged in a non-rotatable manner at the center of a base plate 401 serving as a base of the apparatus. On the base plate 401, a bearing having a rotation axis that coincides with the central axis of the shaft member A 501 and configured by the inner ring 502 and the outer ring 504 is disposed in a manner that fixes the inner ring 502 to the base plate 401. In order to avoid rubbing between the base plate 401 and the bearing outer ring 504, the base plate 401 and the bearing inner ring 502 are fixed with a spacer 503 interposed therebetween. Adapter A505, slip ring 506, adapter B507, gear P404, and rotating plate 405 are integrally fixed to the outer ring 504 of the bearing. A gear M403 to which rotational power is applied by the power unit 402 is disposed so as to mesh with the gear P404. A shaft member A501 is inserted into a hole formed in the center of the rotating plate 405 in a freely rotating manner, and the gear P404 is disposed so that the rotating shaft coincides with the central axis of the shaft member A501. Therefore, the rotational power provided by the power unit 402 is transmitted to the gear P404 via the gear M403, and the components fixed to the bearing outer ring 504 rotate integrally around the shaft member A501.

The shaft member B510 is inserted into a hole formed in the rotating plate 405 and the support plate A408 in a freely rotating manner, and is arranged in parallel with the shaft member A501. The shaft member B510 is fixed with a gear B509 on the base plate 401 side and a gear C406 on the support plate A408 side with the rotating plate 405 interposed therebetween so that the rotating shaft is aligned with the central axis of the shaft member B510. The gear B509 is disposed so as to mesh with the gear A508 fixed so that the central axis of the shaft member A501 coincides with the rotation axis. The gear A508 is fixed to the shaft member A501, and the shaft member A501 does not rotate with respect to the base plate 401. Therefore, the gear A508 cannot rotate by itself. Therefore, with the rotation of the rotating plate 405, the gear B509 moves circularly around the gear A508 while rotating itself. FIG. 6 shows a model showing the relationship between the gear A 508 and the gear B 509 at this time. The absolute rotation angle of the gear B509 when the rotation plate 405 rotates θ1 is θ2, but the gear B509 performs a circular motion around the shaft member A501 in accordance with the rotation of the rotation plate 405. The relative rotation angle with respect to is θ2−θ1 and is obtained by Equation 5. Here, Za is the number of teeth of the gear A508, and Zb is the number of teeth of the gear B509.

  When the gear B509 rotates, the gear C406 connected through the shaft member B510 also rotates at the same time. Gear D407 is arranged so as to mesh with gear C406, and rotational power is transmitted to gear D407. The gear D407 is fixed to a shaft member C511 arranged so that the center axis thereof coincides with the rotation axis of the gear D407 at a position between the rotation plate 405 and the support plate A408. The shaft member C511 is inserted into a hole formed in the rotating plate 405 and the support plate B412 in a freely rotating manner, and is arranged in parallel with the shaft member A501 and the shaft member B510. FIG. 7 shows a model showing the relationship between the gear C406 and the gear D407, and considering that the rotation angles of the gear B509 and the gear C406 are the same, the rotation angle θ4 of the gear D407 accompanying the rotation of the rotating plate 405 is Obtained by. Here, Zc is the number of teeth of the gear C406, and Zd is the number of teeth of the gear D407.

  The front cam 409 is disposed so that the rotation axis thereof coincides with the central axis of the shaft member C511, and is fixed at a position sandwiched between the support plate A408 and the support plate B412. A groove shown in FIG. 8 is dug in the front cam 409, and the cam follower 512 is inserted into the groove so as to be perpendicular to the grooved surface. The cam follower 512 is fixed to a slide plate 410 whose movable range is limited only in the linear direction. Assuming that the intersection of the straight line L parallel to the movable range of the slide plate 410 and the center line of the groove is Pc, Pc reciprocates between the two points in accordance with the rotation of the front cam 409 (FIG. 9). Since the movement of Pc coincides with the movement of the cam follower 512, the slide plate 410 to which the cam follower 512 is fixed performs a reciprocating linear movement. As a result, the rotational motion of the gear D407 can be converted into the reciprocating linear motion of the slide plate 410. Considering the realization of the unit scanning trajectory, the front cam 409 needs to rotate 360 degrees when scanning of the scanning region in the pan direction is completed, that is, when the rotating plate 405 is rotated by θp.

The slide plate 410 is connected to the arm 414 via the rack 411 and the gear E413, and the gear E413 rotates, that is, the angle of the arm 414 changes in accordance with the movement of the slide plate 410. FIG. 10 shows a model showing the relationship between the rack 411 and the gear E413. Considering that the movement distance of the slide plate 410 and the rotation distance of the gear E413 are equal, the relationship between the rotation of the rotation plate 405 and the rotation movement of the gear E413 is expressed by Equation 7. Here, L is the slide width of the slide plate 410, θ5 is the rotation angle of the gear E413, Ze is the number of teeth of the gear E413, and m3 is a module of the gear E413.

As the slide plate 410 reciprocates linearly within the movable range, the gear E413 reciprocally rotates at an angle of 0 to θt with the angle θt / 2 as a reference. Considering this, since the rotation angle of the gear E413 when the slide plate 410 moves to the limit of the movable range is θt / 2, the relationship of Formula 8 is established. Equation 8 indicates that the scanning area in the tilt direction depends on the number of teeth of the gear E 413 and the module and the slide width of the slide plate 410. In the present invention, a reciprocating linear motion is realized by the front cam 409 having a circular groove, and L in FIG. 8 corresponds to the slide width.

  Based on the above principle, the rotation of the rotating plate 405 in the pan direction and the reciprocating rotation of the arm 414 fixed to the gear E 413 in the tilt direction can be realized by the single power unit 402. By mounting the sensor 415 at the tip of the arm 414 so that the detection unit 416 faces the outside of the apparatus, it is possible to recognize the three-dimensional space by the three-dimensional mesh scanning trajectory.

  In order to realize a three-dimensional mesh scanning trajectory, it is necessary to appropriately select the parameters of Equation 6 and Equation 8. The parameter in Equation 6 is the number of teeth of gear A508, gear B509, gear C406, and gear D407. Considering that the scanning in the tilt direction by the unit scanning trajectory is completed when the front cam 409 rotates 360 degrees, it is necessary to select parameters so as to satisfy Equation 9. Since the three-dimensional mesh scanning trajectory is realized by a unit scanning trajectory whose start and end do not coincide with each other, the rotation angle of the rotating plate 405 required to rotate the front cam 409 360 degrees must not be an integral multiple of 360. That is, θp needs to satisfy Equation 3. For example, when a three-dimensional mesh scanning trajectory is realized by a unit scanning trajectory of θp = 350, the condition of Equation 9 can be satisfied if Za = 18, Zb = 18, Zc = 36, and Zd = 35.

  The parameters in Expression 8 are the slide width, the scanning area in the pan direction, the number of teeth of the gear E413, and the module. For example, when a unit scanning trajectory of θt = 90 is realized using the number of teeth 25 and the gear E413 of the module 0.8, the condition of Expression 8 can be satisfied if L = 5π.

  Since the present invention enables a wide range of recognition by a single sensor, it can be introduced to object recognition in a system such as a security system or a mobile robot.

r: distance from the center of the trajectory to the scanning trajectory θ: rotation angle in the pan direction with respect to the starting end of the unit scanning trajectory PS: starting end of the unit scanning trajectory PE: end of the unit scanning trajectory 401: base plate 402: power unit 403: gear M
404: Gear P
405: Rotating plate 406: Gear C
407: Gear D
408: Support plate A
409: Front cam 410: Slide plate 411: Rack 412: Support plate B
413: Gear E
414: Arm 415: Sensor 416: Sensor detection unit 501: Shaft material A
502: Bearing inner ring 503: Spacer 504: Bearing outer ring 505: Adapter A
506: Slip ring 507: Adapter B
508: Gear A
509: Gear B
510: Shaft material B
511: Shaft material C
512: Cam follower d1: Orbit interval L of the three-dimensional mesh-like scanning orbit L1: Three-dimensional mesh-like scanning orbit θ1: The rotation angle of the rotating plate θ2: Absolute rotation angle of the gear B 901: Groove Ln dug in the front cam: Slide Straight line Pc parallel to plate movement direction: intersection point of Ln and groove center line r1: longest distance from front cam rotation axis to groove center r2: shortest distance L from front cam rotation axis to groove center L: Pc travel width d2: orbital spacing of spiral scanning trajectory L2: spiral scanning orbit

Claims (5)

By superimposing multiple unit scan trajectories with different start and end points obtained by simultaneously changing the rotation angle in the pan and tilt directions, a 3D mesh scan trajectory is realized by scanning the 3D space in a mesh shape. A three-dimensional scanning device characterized by:
  A base plate at the bottom of the device, a shaft A fixed perpendicular to the base plate, a rotating plate that can freely rotate around the shaft A, and a single power device that supplies rotational power The gear P fixed to the rotating plate in such a way that the rotational power is transmitted to the rotating plate, the rotating shaft being coincident with the central axis of the shaft member A, and the rotating shaft being coincident with the central axis of the shaft member A The gear A that is fixed to the shaft A and does not rotate by itself, the gear B that meshes with the gear A and rotates around the gear A by itself as the rotating plate rotates, and the center shaft that rotates the gear B The shaft B is fixed to the gear B so as to coincide with the shaft, and is fixed to the shaft B such that the rotation shaft coincides with the central axis of the shaft B. The gear C on the rotating plate that rotates by itself according to the rotation of the gear B is assembled on the rotating plate so as to mesh with the gear C. A gear D, a support plate A supporting the gear C and the gear D in a sandwiched manner with the rotary plate, a conversion mechanism assembled on the rotary plate for converting the rotary motion of the gear D into a reciprocating linear motion, The slide plate that reciprocates linearly with the motive power, the rack that is assembled in parallel with the movable range of the slide plate, and the slide plate that is connected to the slide plate via the gear E that meshes with the rack. It has an arm that performs reciprocating rotational movement in the tilt direction, and a support plate B to which the arm is fixed. By driving the power unit, the rotation plate, gear B, gear C, gear D, support plate A, conversion mechanism, slide The plate, rack, gear E, arm, and support plate B are integrally rotated in the pan direction, and the rotational power of the gear B generated thereby is the gear C, gear D, conversion mechanism, slide plate, rack, gear E, Ah The three-dimensional spatial scanning by the three-dimensional mesh scanning trajectory is realized without the rotational direction control of the driving device by the arm performing reciprocating rotational movement in the tilt direction. The three-dimensional scanning device according to 1.   The three-dimensional scanning according to claim 2, wherein the mechanism for converting the rotational motion into a reciprocating linear motion is realized by a front cam in which a groove is formed in a plate and a cam follower driven in accordance with the groove. apparatus.   The three-dimensional scanning device according to claim 3, wherein the groove formed in the front cam is circular. The three-dimensional using the three-dimensional scanning device according to any one of claims 2 to 4, wherein a sensor is added to a tip of the arm to realize recognition of a three-dimensional space by the sensor. Positioning device.

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