Imaging apparatus, control method, and program

Abstract

To improve vibration resistance and impact resistance.SOLUTION: An imaging apparatus includes: a plurality of imaging means arranged along a circumferential direction; a plurality of holding means that is rotatable about a rotation axis orthogonal to the circumferential direction and hold the plurality of respective imaging means; biasing means that biases the plurality of holding means in a direction parallel to the rotation axis; and control means that controls the biasing force of the biasing means so that the biasing force of the biasing means is in any of a plurality of states including a first state and a second state. The biasing force in the second state is larger than the biasing force in the first state.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an imaging apparatus, a control method, a program, and the like. [Background technology]

[0002] There is known a multi-lens camera that is equipped with a plurality of imaging means arranged along the circumferential direction and can capture the surroundings without blind spots. Patent Document 1 discloses a multi-lens camera that is configured to be able to drive the imaging means using a mechanism in which a pinion and an internal gear are meshed. This multi-lens camera can rotate the imaging means in the circumferential direction by rotating the pinion arranged on the imaging means with a motor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2021 / 0058556 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the multi-lens camera disclosed in Patent Document 1, due to its structure, it is not possible to reduce the backlash between the pinion and the internal gear to zero. Therefore, there is a problem that the imaging means rattles in the circumferential direction even if the pinion is controlled to be stationary. If there is rattle in the imaging means, the imaging means will move when the multi-lens camera is subjected to vibration or impact, which may make it difficult to capture an image at the desired angle of view.

[0005] The present invention has been made in consideration of the above-mentioned problems, and has an object to improve vibration resistance and impact resistance. [Means for solving the problem]

[0006] The present invention is an imaging device having a plurality of imaging means arranged along a circumferential direction, a plurality of holding means rotatable around a rotation axis perpendicular to the circumferential direction and holding each of the plurality of imaging means, a biasing means for biasing the plurality of holding means in a direction parallel to the rotation axis, and a control means for controlling the biasing force of the biasing means so that the biasing force of the biasing means is in one of a plurality of states including a first state and a second state, and is characterized in that the biasing force in the second state is greater than the biasing force in the first state. Effect of the Invention

[0007] According to the present invention, it is possible to improve vibration resistance and impact resistance. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view showing an example of the external configuration of a multi-lens camera according to a first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view showing an example of the configuration of a multi-lens camera. [Diagram 3] FIG. 1 is a block diagram showing an example of a configuration of a security system. [Figure 4] FIG. 2 is a perspective view showing an example of a configuration of a camera unit. [Diagram 5] FIG. 4 is a diagram showing an example of a configuration around a main shaft in a free state. [Figure 6] FIG. 4 is an exploded perspective view showing an example of a configuration of a cam mechanism. [Figure 7] 11 is a diagram showing an example of a configuration around a main shaft in a locked state. FIG. [Figure 8] 4 is a flowchart showing an example of the operation of the multi-lens camera. [Figure 9] FIG. 13 is a diagram illustrating an example of the configuration of a camera array according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. <First embodiment> First, a multi-lens camera 100 serving as an imaging apparatus according to the first embodiment will be described.

[0010] 1 is a perspective view showing an example of the external configuration of a multiple-eye camera 100. The housing of the multiple-eye camera 100 is composed of a bottom cover 200 and a dome 250, and the bottom cover 200 can be attached to a ceiling or the like. The multiple-eye camera 100 is used for the purpose of ensuring security such as surveillance, and is capable of capturing images with a wide angle of view using multiple imaging means.

[0011] Multi-lens camera 100 has camera units 110A-D, which are arranged along the circumferential direction. Camera units 110A-D also have lens-barrel units 111A-D and camera holders 112A-D as holding means for holding lens-barrel units 111A-D so that they can tilt and rotate. Lens-barrel units 111A-D include imaging sensors and lenses, and function as imaging means of multi-lens camera 100. Note that, although the number of imaging means is four in this embodiment, multi-lens camera 100 may have multiple imaging means, and the number is not limited.

[0012] 2 is an exploded perspective view showing an example of the configuration of the multi-lens camera 100. A main shaft 220 is fixed to a base 210 serving as a support means. When ring portions 113A-D formed on camera holders 112A-D engage with the main shaft 220, the camera units 110A-D can rotate around a central axis O of the main shaft 220 (around a rotation axis perpendicular to the circumferential direction). In the following description, the rotation of the main shaft 220 around the central axis O is referred to as "shift rotation."

[0013] FIG. 3 is a block diagram showing an example of the configuration of a security system 300 including the multiple-eye camera 100. The security system 300 includes the multiple-eye camera 100 and a client device 400 (information processing device). The multiple-eye camera 100 is communicably connected to the client device 400, which is an external device, via a network 500. The multiple-eye camera 100 includes a rotation driving means which will be described in detail in FIG. 5, and can shift and rotate the camera units 110A-D based on a command from the client device 400. In other words, the user can rotate the camera units 110A-D using the client device 400 to adjust the angle of view.

[0014] FIG. 4 is a perspective view showing an example of the configuration of camera unit 110A. Camera units 110B to 110D have the same configuration as in FIG. 4, and the following description will be omitted. Camera holder 112A has pinion 114A and a motor (not shown). Pinion 114A is connected to the motor so as to be able to transmit torque, and rotates by the driving force of the motor. Pinion 114A meshes with gear section 211 (internal gear) provided on base 210, so that the entire camera unit 110A can shift and rotate by rotating the motor. Pinion 114A, the motor, and gear section 211 are an example of a rotation drive means.

[0015] Cable 115A transmits video signals, control signals, motor control signals, and the like for barrel unit 111A, and passes through the hollow portion of main shaft 220 to be connected to a main board (not shown) inside bottom cover 200. A control unit is mounted on the main board as control means for controlling multi-eye camera 100 as a whole.

[0016] FIG. 5 is a diagram showing the periphery of the main shaft 220 and the ring portions 113A to 113D. A cam mechanism 230 serving as a biasing means is provided at the bottom of main shaft 220. Cam mechanism 230 has a first cam 231, a second cam 232, a spring 233, and a washer 234. Cam mechanism 230 biases camera units 110A-D in the upward direction in FIG. 5 (direction parallel to the rotation axis) via ring portions 113A-D by spring 233. This biasing force prevents camera units 110A-D from rattling in the vertical direction.

[0017] 6(a) and (b) are exploded perspective views showing an example of the configuration of the cam mechanism 230. FIG. 6(a) is a perspective view seen from above, and FIG. 6(b) is a perspective view seen from below. The first cam 231 and the second cam 232 are engaged with the main shaft 220 by inserting the main shaft 220 into a hole formed by penetrating vertically. The first cam 231 can rotate with respect to the main shaft 220. On the other hand, the second cam 232 cannot rotate with respect to the main shaft 220 because it has a key part 235, and can move only in a direction parallel to the central axis O of the main shaft 220. The first cam 231 can be rotated by a cam drive mechanism 236 as a cam drive means composed of a motor and gears. In addition, the first cam 231 is provided with a photointerrupter 237 as a position detection means, and the photointerrupter 237 can detect the movement of the second cam 232. In addition, the position detection means of this embodiment directly detects the movement of the second cam 232, but it is sufficient if it can detect the state of the cam mechanism 230, and it may be configured to detect, for example, the position and phase of the first cam 231, the motor shaft of the cam drive mechanism 236, etc.

[0018] In addition, the first cam 231 has a first inclined surface portion 238, and the second cam 232 has a second inclined surface portion 239A and a second inclined surface portion 239B. Either the second inclined surface portion 239A or the second inclined surface portion 239B is configured to come into contact with the first inclined surface portion 238.

[0019] A state in which first inclined surface portion 238 and second inclined surface portion 239A are in contact with each other is a free state (first state), and a state in which first inclined surface portion 238 and second inclined surface portion 239B are in contact with each other is a locked state (second state). FIG. 5 shows the state of main shaft 220 and the periphery of ring portions 113A-D in the free state, and FIG. 7 shows the state in the locked state. When cam drive mechanism 236 rotates first cam 231 in the direction of arrow α in FIG. 6, the free state and the locked state alternate, and photointerrupter 237 can detect which state it is in.

[0020] In the locked state, second cam 232 is moved upward in FIG. 7 compared to the free state. Therefore, spring 233 in the locked state is compressed more than in the free state, and the biasing force of cam mechanism 230 is greater. When the biasing force is greater, the load torque when shifting and rotating camera units 110A-D is increased due to the frictional force generated in ring portions 113A-D. In other words, in the locked state (second state), the driving load of camera units 110A-D is greater than in the free state (first state).

[0021] Fig. 8 is a flowchart showing an example of the operation of the multi-lens camera 100. The flowchart in Fig. 8 is realized by the control unit executing a program stored in a memory mounted on the main board, for example. Here, a control method is shown in which the control unit controls the cam mechanism 230 via the cam drive mechanism 236 and drives the camera units 110A-D to shift and rotate.

[0022] In S401, a user issues a command to the multi-lens camera 100 via the client device 400 to shift and rotate the camera units 110A-D, and the client device 400 transmits command information to the multi-lens camera 100. The multi-lens camera 100 receives the command information from the client device 400.

[0023] In S402, the control unit of the multiple-eye camera 100 checks whether the state of the cam mechanism 230 is free or locked using the photointerrupter 237. If the cam mechanism 230 is in the locked state, the process proceeds to S403, and if it is in the free state, the process proceeds to S404.

[0024] In S403, the control unit of the multiple-eye camera 100 controls the cam drive mechanism 236 to transition the cam mechanism 230 from the locked state to the free state before driving and shifting the camera units 110A to 110D to rotate. In S404, the control unit of the multiple-eye camera 100 drives and shifts and rotates the camera units 110A to 110D based on the received command information.

[0025] In S405, after camera units 110A-D have come to a standstill, the control unit of camera array 100 controls cam drive mechanism 236 to transition cam mechanism 230 from the free state to the locked state, thereby completing the processing of the flowchart in FIG.

[0026] In this way, the control unit of the multi-eye camera 100 puts the cam drive mechanism 236 in a free state when the camera units 110A-D are driven to shift and rotate, and puts the cam drive mechanism 236 in a locked state when the camera units 110A-D are stationary. In a configuration having pinions 114A-D and gear unit 211 as in this embodiment, backlash occurs between pinions 114A-D and gear unit 211, causing rattling in the direction of shift rotation in camera units 110A-D. Therefore, when impact or vibration is applied to multi-lens camera 100, camera units 110A-D may shift in the shift direction, causing a change in the angle of view. According to the control by the control unit of multi-lens camera 100 described above, the load of the shift rotation increases by keeping cam drive mechanism 236 in a locked state when camera units 110A-D are stationary, so that the angle of view deviation can be suppressed.

[0027] As described above, according to this embodiment, the control unit of the multiple-lens camera 100 controls the biasing force of the cam mechanism 230 to be in the first state or the second state. Here, since the biasing force in the second state is greater than the biasing force in the first state, by setting the camera in the second state when the imaging means is not shifting and rotating, deviation in the angle of view due to vibration or impact can be suppressed, thereby improving vibration resistance and impact resistance.

[0028] <Second embodiment> In the second embodiment, a configuration having a torque limiter will be described in order to reduce the possibility of component damage compared to the first embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals and will not be described as necessary.

[0029] In this embodiment, the pinions 114A-D shown in Fig. 4 have torque limiters (not shown). The torque limiters function to cause the pinions 114A-D to spin freely when a load torque of a certain level or more is applied to the pinions 114A-D. Therefore, damage to the pinions 114A-D and the gear portion 211 can be prevented when a load higher than expected is applied to the pinions 114A-D due to a control error.

[0030] Here, as an example of a case where a load larger than expected is applied to the pinions 114A-D, a case where an error occurs when detecting the state of the cam mechanism 230 in S402 of the flow chart shown in FIG. 8 is considered. If an error occurs and the process proceeds to S404 with the cam mechanism 230 in a locked state, the camera units 110A-D are shifted and rotated while a large rotation load is applied, and a load larger than expected is applied to the pinions 114A-D and the gear unit 211. In this embodiment, the torque limiter causes the pinions 114A-D to rotate freely while the torque applied to the pinions 114A-D is equal to or greater than a certain level, thereby releasing the connection between the motor and the pinions 114A-D. Therefore, the load torque applied to the pinions 114A-D and the gear unit 211 can be suppressed to a certain level or less, thereby reducing the possibility of damage to parts.

[0031] Thus, according to this embodiment, the torque limiter disconnects the motor from the pinions 114A-D while the torque applied to the pinions 114A-D is equal to or greater than a certain level, thereby improving vibration resistance and impact resistance.

[0032] <Third embodiment> In the third embodiment, a multi-lens camera 600 having a different configuration from that of the first embodiment will be described. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0033] FIG. 9(a) is an exploded perspective view of the multi-lens camera 600. The camera holders 112A-D of this embodiment are formed with arcuate portions 713A-D. The arcuate portions 713A-D protrude from the camera holders 112A-D toward the main shaft 820. The inner surface of the arcuate portion 713 on the main shaft 820 side is formed as an arcuate curved surface and faces the outer circumferential surface of the main shaft 820. The arcuate portions 713A-D also have protruding engagement portions 714 at their upper ends that engage with the main shaft 820. Meanwhile, the main shaft 820 has a flange portion 821 at its upper end. The flange portion 821 has groove-shaped engaged portions 822 at its lower surface with which the engagement portions 714 of the arcuate portions 713A-D engage (see FIG. 9(b)).

[0034] 9(b) is a cross-sectional view showing a state in which the engaging portions 714 of the arc portions 713A-D of the camera holders 112A-D are engaged with the engaged portions 822 of the main shaft 820. The engaging portions 714 engage with the engaged portions 822, thereby restricting the movements of the camera units 110A-D in the shift rotation direction. Note that the configuration for restricting the movements of the camera units 110A-D in the shift rotation direction is not limited, and various modifications and variations are possible.

[0035] Further, a cam mechanism 230 is disposed below the main shaft 820, and the cam mechanism 230 biases the arcuate portions 713A-D upward. The cam mechanism 230 uses a wave washer 933 instead of the spring 233 of the first embodiment. The configuration in which the biasing force is controlled by moving the cam mechanism 230 and the lock state and the free state are switched is the same as in the first embodiment.

[0036] In the first embodiment, cam mechanism 230 is configured to bias ring portions 113A-D, and in this embodiment, cam mechanism 230 is configured to bias arc portions 713A-D, but the form is not limited as long as the structure is capable of biasing a portion of camera holders 112A-D.

[0037] <Other embodiments> The present invention can also be realized by supplying a program for implementing one or more of the functions of the above-described embodiments to a system or device via a network or a recording medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

[0038] The present invention has been described above in detail based on a preferred embodiment thereof, but the present invention is not limited to the specific embodiment, and various forms that do not deviate from the gist of the present invention are also included in the present invention.

[0039] In the above embodiment, the control unit of the multi-lens camera 100 controls the biasing force of the cam mechanism 230 to be in a free state (first state) or a locked state (second state), but this is not limited to the above. The biasing force of the cam mechanism 230 is configured to be in a third state different from the first state and the second state, and the control unit may control the biasing force to be in any one of a plurality of states including the first state and the second state.

[0040] The disclosure of this embodiment also includes the following configurations. (Configuration 1) A plurality of imaging means arranged along a circumferential direction; a plurality of holding means that are rotatable around a rotation axis perpendicular to the circumferential direction and that hold the plurality of imaging means, respectively; a biasing means for biasing the plurality of holding means in a direction parallel to the rotation axis; a control unit that controls the biasing force of the biasing unit so that the biasing force of the biasing unit is in one of a plurality of states including a first state and a second state, The imaging device, wherein the biasing force in the second state is greater than the biasing force in the first state. (Configuration 2) The imaging device according to configuration 1, further comprising a rotation drive means for driving the holding means around the rotation axis. (Configuration 3) The imaging device described in configuration 2, wherein the control means controls the biasing means to a first state before the holding means is driven by the rotational driving means, and controls the biasing means to a second state after the holding means is driven by the rotational driving means and then stops. (Configuration 4) the biasing means includes a first cam, a second cam that contacts the first cam, and a spring that contacts the second cam to generate the biasing force; the first cam is disposed rotatably about the rotation axis, The imaging device described in any one of configurations 1 to 3, wherein the second cam is arranged so as to be movable in a direction parallel to the rotation axis when the first cam rotates. (Configuration 5) a cam drive means for rotating the first cam; and a position detection means for detecting a position of the second cam, 5. The imaging device according to configuration 4, wherein the control means controls the cam drive means to rotate the first cam based on the position of the second cam detected by the position detection means. (Configuration 6) The present invention further includes a support means for supporting the plurality of holding means so as to be rotatable around a rotation axis perpendicular to the circumferential direction, 6. The imaging device according to claim 2, wherein the rotational driving means comprises a motor arranged in the holding means, a pinion connected to the motor, and an internal gear provided in the support means and meshing with the pinion. (Configuration 7) The pinion has a torque limiter, 7. The imaging device according to configuration 6, wherein the torque limiter disconnects the motor from the pinion while a torque applied to the pinion is equal to or greater than a certain value. (Method 1) A plurality of imaging means arranged along a circumferential direction; a plurality of holding means that are rotatable around a rotation axis perpendicular to the circumferential direction and that hold the plurality of imaging means, respectively; and a biasing unit that biases the plurality of holding units in a direction parallel to the rotation axis, a control step of controlling the biasing force of the biasing means so that the biasing force of the biasing means is in one of a plurality of states including a first state and a second state; A method for controlling an imaging device, wherein the biasing force in the second state is greater than the biasing force in the first state. (Program 1) A program for causing a computer to execute the control steps according to method 1. (Recording medium 1) A computer-readable recording medium storing a program for causing a computer to execute the control steps according to method 1. [Explanation of symbols]

[0041] 100, 600: Multi-lens camera 110A-D: Camera unit 111A-D: Lens barrel unit 112A-D: Camera holder 210: Base 220, 820: Main shaft 230: Cam mechanism

Claims

1. A plurality of imaging means arranged along a circumferential direction; a plurality of holding means that are rotatable around a rotation axis perpendicular to the circumferential direction and that hold the plurality of imaging means, respectively; a biasing means for biasing the plurality of holding means in a direction parallel to the rotation axis; a control unit that controls the biasing force of the biasing unit so that the biasing force of the biasing unit is in one of a plurality of states including a first state and a second state, The imaging device, wherein the biasing force in the second state is greater than the biasing force in the first state.

2. 2. The imaging apparatus according to claim 1, further comprising a rotation drive means for driving the holding means about the rotation axis.

3. 3. The imaging device according to claim 2, wherein the control means controls the biasing means to the first state before the holding means is driven by the rotational driving means, and controls the biasing means to the second state after the holding means has been driven by the rotational driving means and then stopped.

4. the biasing means includes a first cam, a second cam that contacts the first cam, and a spring that contacts the second cam to generate the biasing force, the first cam is disposed rotatably about the rotation axis, 4. The imaging device according to claim 1, wherein the second cam is arranged to be movable in a direction parallel to the rotation axis when the first cam rotates.

5. a cam driving means for rotating the first cam; and a position detection means for detecting a position of the second cam, 5. The image pickup apparatus according to claim 4, wherein the control means controls the cam drive means to rotate the first cam based on the position of the second cam detected by the position detection means.

6. The present invention further includes a support means for supporting the plurality of holding means so as to be rotatable around a rotation axis perpendicular to the circumferential direction, 4. The imaging device according to claim 2, wherein the rotation drive means comprises a motor disposed in the holding means, a pinion connected to the motor, and an internal gear provided in the support means and meshing with the pinion.

7. The pinion has a torque limiter.

7. The imaging device according to claim 6, wherein the torque limiter disconnects the motor from the pinion while a torque applied to the pinion is equal to or greater than a certain value.

8. A plurality of imaging means arranged along a circumferential direction; a plurality of holding means that are rotatable around a rotation axis perpendicular to the circumferential direction and that hold the plurality of imaging means, respectively; and a biasing unit that biases the plurality of holding units in a direction parallel to the rotation axis, a control step of controlling the biasing force of the biasing means so that the biasing force of the biasing means is in one of a plurality of states including a first state and a second state; A method for controlling an imaging device, wherein the biasing force in the second state is greater than the biasing force in the first state.

9. A program for causing a computer to execute the control steps according to claim 8.

10. A computer-readable recording medium storing a program for causing a computer to execute the control steps according to claim 8.

Images