JP2007225342A - Three-dimensional measuring device and autonomously moving device provided with three-dimensional measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional measuring device capable of changing a measurement condition corresponding to measurement object. <P>SOLUTION: The three-dimensional measuring device 18 of this invention comprises the laser range sensor 20 for measuring the distance data, the rotational device 30 for rotating the laser range sensor 20, the encoder 38 for detecting the rotational angle of the rotational device 30; the arithmetic part 52a connected with the laser range sensor 20 and the encoder 38; the setting means 52c for setting the rotational period; and the rotation control part 52b for driving the rotation device 30 with set rotation period. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for measuring the shape of a space (the shape of an object in the space) in three dimensions.

As a measuring apparatus for measuring the shape of an object in space in three dimensions, a three-dimensional measuring apparatus disclosed in Patent Document 1 is known. This three-dimensional measuring device is a distance measuring device that measures distance data on a scanning surface scanned with a light beam by scanning the light beam around a scanning axis, and rotates the distance measuring device around a rotation axis orthogonal to the scanning axis. And a calculation device that calculates three-dimensional distance data using the distance data obtained by the distance measurement device and the rotation angle of the rotation device.
In this measuring device, the distance measuring device changes the direction of irradiating the light beam around the scanning axis while irradiating the light beam. The distance measuring device emits a light beam at each irradiation angle and detects whether or not an object exists in the direction in which the light beam is irradiated. When an object is present in the direction in which the light is irradiated, the distance to the object is measured. That is, the distance measuring apparatus measures two-dimensional distance data represented by an angle around the scanning axis irradiated with the light beam and a distance to the object. Simultaneously with the measurement of the two-dimensional distance data, the rotation device rotates the distance measurement device around the rotation axis, and the irradiation direction of the light beam by the distance measurement device is changed around the rotation axis. At that time, a rotation angle around the rotation axis by the rotation device (that is, an angle around the rotation axis at which the distance measuring device irradiates light) is detected by the sensor. If the angle around the scanning axis irradiated with the light beam and the angle around the rotation axis are known, the direction irradiated with the light beam can be specified. Therefore, the calculation device calculates the three-dimensional distance data using the two-dimensional distance data measured by the distance measurement device and the rotation angle of the rotation device detected by the sensor.

JP-T-2001-524211

When the three-dimensional measurement apparatus is to be mounted on another apparatus, it is preferable to change measurement conditions such as the measurement range and measurement accuracy of the three-dimensional measurement apparatus according to the measurement purpose and the like. For example, when a three-dimensional measuring device is mounted on an autonomous mobile device and an obstacle is to be detected by the three-dimensional measuring device, it is important to measure the spatial shape in the traveling direction of the autonomous mobile device. Accordingly, the three-dimensional measuring device is required to limit the measurement range so as to measure only the spatial shape in the traveling direction of the self-supporting mobile device or to increase the measurement accuracy (resolution) in the traveling direction. However, in the measurement apparatus of Patent Document 1, measurement conditions cannot be changed, and thus an area unnecessary for the autonomous mobile apparatus is measured. In addition, there is a problem that a long time is required for measurement if a desired resolution is obtained.
As described above, the three-dimensional measurement apparatus disclosed in Patent Document 1 has a problem in that measurement according to a measurement purpose cannot be performed because measurement conditions such as a measurement range and measurement accuracy cannot be changed.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a three-dimensional measurement apparatus capable of changing measurement conditions according to a measurement purpose or the like.

The three-dimensional measuring apparatus of the present invention is equipped with a distance measuring device for measuring distance data on a scanning surface scanned with a light beam by scanning the light beam around a scanning axis, and the distance measuring device is attached to scan the distance measuring device. 3D distance data using a rotation device that rotates around a rotation axis that is not parallel to the axis, a sensor that detects a rotation angle of the rotation device, distance data that is input from the distance measurement device, and rotation angle that is input from the sensor. An arithmetic device for calculating, a setting means for setting a rotation cycle and / or a rotation angle range of the rotation device, and a rotation control device for driving the rotation device within the set rotation cycle and / or rotation angle range.
In this three-dimensional measuring apparatus, the rotation cycle and / or rotation angle range is set by the setting means, and the rotation control device drives the rotation device within the set rotation cycle and / or rotation angle range. Therefore, it is possible to change the rotation period and / or the rotation angle range in which the distance measuring device rotates by the setting means.
When the rotation period at which the distance measuring device rotates is changed, the angular velocity at which the distance measuring device rotates is changed. When the angular velocity at which the distance measuring device rotates is changed, the angular pitch around the rotation axis at which the distance measuring device irradiates light is changed. The angle pitch at which the distance measuring device irradiates light is the density of measurement points (that is, the resolution of measurement) when measuring three-dimensional distance data. Therefore, the above-described three-dimensional measuring apparatus can change the measurement resolution by setting the period in which the distance measuring apparatus rotates according to the measurement purpose and the like.
When the rotation angle range in which the distance measuring device rotates is changed, the scanning range in which the distance measuring device scans the light beam (that is, the measurement range of the three-dimensional distance data) is changed. Therefore, the above-described three-dimensional measurement apparatus can change the measurement range of the distance measurement apparatus according to the measurement purpose and the like.

In the above-described three-dimensional measuring apparatus, the rotation control apparatus can drive the rotation apparatus based on the rotation trajectory calculated using the set rotation period and / or rotation angle range. In this case, it is preferable that the calculated rotation trajectory has a constant angular velocity within a predetermined angle range from the center of the set rotation angle range.
According to such a configuration, measurement can be performed with uniform resolution within a predetermined angle range from the center of the rotation angle range.

In the above-described three-dimensional measurement apparatus, the arithmetic unit corrects the rotation angle input from the sensor using the time when the light beam scans one scanning plane by the distance measurement apparatus and the angular velocity of the rotation apparatus, and obtains the three-dimensional distance data. It is preferable to calculate.
According to such a configuration, the deviation between the data input timing from the distance measuring device to the arithmetic device and the data input timing from the sensor to the arithmetic device is corrected, and the three-dimensional distance data can be calculated with high accuracy. it can.

The present invention also provides an autonomous mobile device that moves to a target point while avoiding an obstacle by measuring three-dimensional distance data while changing measurement conditions according to the situation.
That is, the autonomous mobile device of the present invention is equipped with a distance measuring device for measuring distance data on a scanning surface scanned with a light beam by scanning the light beam around a scanning axis, and the distance measuring device. A rotation device that rotates around a rotation axis that is not parallel to the scanning axis, a moving body on which the rotation device is mounted, a sensor that detects a rotation angle of the rotation device, distance data that is input from the distance measurement device, and a sensor that is input. A computing device that computes three-dimensional distance data using the rotation angle, a moving body control device that controls the moving direction and speed of the moving body using the three-dimensional distance data computed by the computing device, A setting unit that sets a rotation cycle and / or a rotation angle range; and a rotation control device that drives the rotation device within the set rotation cycle and / or rotation angle range.
Even in this autonomous mobile device, the rotation cycle and / or the rotation angle range of the rotation device can be changed by changing the rotation cycle and / or the rotation angle range by the setting means. Therefore, the setting means changes the rotation period and / or the rotation angle range of the rotating device according to the status of the autonomous mobile device, so that the measurement conditions of the distance measuring device are changed according to the status of the autonomous mobile device, and autonomous movement 3D distance data necessary for Since the moving body control device controls the moving direction and moving speed of the moving body using the measured three-dimensional distance data, the autonomous moving device can move to the destination point while avoiding obstacles.

In the above-described autonomous mobile device, it is preferable that the setting means sets the rotation cycle of the rotating device according to the moving speed of the moving body.
According to such a configuration, three-dimensional distance data can be measured with a necessary resolution in accordance with the speed of the moving object. For example, when the moving speed of the moving body is high, the rotation period is shortened so that the three-dimensional distance data can be acquired in a short time although the resolution is low. On the other hand, when the moving speed of the moving body is low, the rotation cycle is lengthened and three-dimensional distance data with high resolution is acquired over time.

In the above-described autonomous mobile device, it is preferable that the arithmetic device corrects the three-dimensional distance data using the moving amount of the moving body.
That is, the three-dimensional distance data obtained by the distance measuring device is represented by a relative position with respect to the position of the autonomous mobile device. Therefore, if the three-dimensional distance data is measured while the autonomous mobile device is moving, the reference point moves, so that the three-dimensional distance data cannot be accurately measured as it is.
According to the above-described autonomous mobile device, since the three-dimensional distance data obtained by the distance measuring device is corrected using the moving amount of the moving body, the three-dimensional distance data can be represented by an absolute position. Therefore, the autonomous mobile device can measure accurate three-dimensional shape data with the distance measuring device while moving.

The autonomous mobile device described above further includes a sensor that detects an inclination angle with respect to the vertical axis of the autonomous mobile device, and the rotation control device corrects a rotation angle range for rotating the distance measuring device based on the inclination angle detected by the sensor. It is preferable to do.
According to such a configuration, when the autonomous mobile device is tilted with respect to the vertical axis, the rotation angle range for rotating the distance measuring device is corrected based on the tilt angle detected by the sensor. For this reason, three-dimensional distance data can be measured in the same measurement range as when the autonomous mobile device is not tilted (for example, within a predetermined angle range with respect to the traveling direction of the moving body).

The main features of the embodiments described in detail below are listed first.
(Mode 1) An autonomous mobile device includes an autonomous mobile body and a three-dimensional measuring device mounted on the autonomous mobile body.
(Mode 2) A three-dimensional measuring apparatus is provided with a laser range sensor for measuring distance data on a scanning surface scanned with a laser by scanning the laser around a scanning axis, and a laser range sensor. Three-dimensional distance data using a rotation device that rotates around a pitch axis perpendicular to the scanning axis, a sensor that detects a rotation angle of the rotation device, distance data input from a laser range sensor, and a rotation angle input from the sensor And a setting means for setting a rotation cycle and / or a rotation angle range of the rotation device, and a rotation control unit for driving the rotation device in the set rotation cycle and / or rotation angle range.
(Mode 3) The autonomous mobile body is a four-wheel carriage that moves by driving four wheels, and a movement that controls the moving direction and speed of the four-wheel carriage by controlling the rotation speed of the wheels of the four-wheel carriage. Consists of a body control device.
(Mode 4) The rotation control device drives the rotation device based on the rotation trajectory calculated using the set rotation period and rotation angle range.
(Embodiment 5) The calculated rotation trajectory has a constant angular velocity within a predetermined angle range from the center of the set rotation angle range.
(Mode 6) The arithmetic unit of the three-dimensional measuring device corrects the rotation angle input from the sensor using the time when the laser scans one scanning surface by the laser range sensor and the angular velocity of the rotating device, and corrects the three-dimensional distance data. Is calculated.
(Mode 7) The calculation device calculates three-dimensional distance data by correcting the rotation angle input from the sensor based on the time delay from the scanning of the laser by the laser range sensor to the input of the distance data to the calculation device. .
(Mode 8) The setting means sets the rotation cycle of the rotating device according to the moving speed of the moving body.
(Mode 9) The arithmetic device corrects the three-dimensional distance data using the moving amount of the moving body.

  An autonomous mobile device according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the autonomous mobile device 10 includes an autonomous mobile body 16 and a three-dimensional measuring device 18 mounted on the autonomous mobile body 16.

(A) Configuration of Autonomous Moving Body 16 The autonomous moving body 16 is configured by a four-wheel cart 40 and a control device 14 that controls the four-wheel cart 40.
The four-wheel carriage 40 includes a carriage main body 42 and four wheels 44 a to 44 d that support the carriage main body 42. On the carriage main body 42, the three-dimensional measuring device 18 is mounted. Motors 46a to 46d are connected to the wheels 44a to 44d. When the motors 46a to 46d rotate, the wheels 44a to 44d rotate and the autonomous mobile device 10 moves. The moving speed of the autonomous mobile device 10 can be adjusted by adjusting the rotational speed of the wheels 44a to 44d, and the moving direction of the autonomous mobile device 10 can be changed by changing the rotational speed of the left and right wheels 44a to 44d. Encoders 48a to 48d are respectively connected to the motors 46a to 46d, and the encoders 48a to 48d detect the rotation amounts o, p, q, and r (that is, wheel rotation amounts) of the motors 46a to 46d. The encoders 48 a to 48 d are electrically connected to the control device 14. The wheel rotation amounts o, p, q, and r detected by the encoders 48 a to 48 d are input to the control device 14.
The control device 14 includes a microprocessor having a CPU, ROM, and RAM. The control device 14 is mounted on the carriage main body 42 and is electrically connected to the motors 46a to 46d and the encoders 48a to 48d. An input device (not shown) is connected to the control device 14, and a destination is set (input) to the control device 14 by the input device. The control device 14 is electrically connected to a control device 52 of the three-dimensional measurement device 18 described later. As will be described in detail later, the control device 52 of the three-dimensional measuring device 18 calculates a three-dimensional map, and the three-dimensional map is input to the control device 14. The control device 14 calculates target rotation speeds of the motors 46a to 46d based on the input three-dimensional map and the destination. Based on the deviation between the rotational speeds of the motors 48a to 48d calculated based on the rotation amounts o, p, q, and r input from the encoders 48a to 48d and the calculated target rotational speed, The control command value is output to 48a to 48d. As each motor 48a to 48d is driven based on the control command value, the autonomous mobile device 10 moves toward the destination.
The control device 14 sets measurement conditions of the three-dimensional measurement device 18 (specifically, a rotation period T, a rotation angle range W, and a rotation center C of the rotation device 30 described later), and the set measurement conditions are set in the control device 52. To enter. Further, the control device 14 calculates the position and traveling direction of the autonomous mobile body 16 based on the rotation amounts o, p, q, and r input from the encoders 48a to 48d, and calculates the calculated position of the autonomous mobile body 16 and The traveling direction is input to the control device 52.

(B) Configuration of 3D Measurement Device 18 The 3D measurement device 18 includes a laser range sensor 20, a rotation device 30 that rotates the laser range sensor 20, and a control device 52. The rotating device 30 and the control device 52 are installed on the four-wheel carriage 40. The laser range sensor 20 is mounted on the rotating device 30.

(B-1) Configuration of Rotating Device 30 The rotating device 30 includes a frame 35, a motor 37, and an encoder 38 that detects the rotation angle of the motor 37.
The frame 35 includes a base portion 35a fixed on the four-wheel carriage 40 and two vertical frames 35b and 35c extending upward from both ends of the base portion 35a. Through holes 36a and 36b are formed near the ends of the vertical frames 35b and 35c, respectively (see FIG. 3). Shaft portions 22a and 22b of a laser range sensor 20 described later are inserted into the through holes 36a and 36b, respectively. When the shaft portions 22a and 22b are respectively attached to the through holes 36a and 36b of the vertical frames 35b and 35c, the laser range sensor 20 is rotatably supported between the vertical frames 35b and 35c (details are shown in FIG. 1). It is supported rotatably around the rotation axis 32).
A motor 37 is installed on the vertical frame 35b. The motor 37 is connected to the shaft portion 22 a of the laser range sensor 20. When the motor 37 rotates, the shaft portion 22a rotates accordingly, and the shaft portion 22a rotates, so that the laser range sensor 20 rotates around the rotation shaft 32 with respect to the vertical frames 35b and 35c. The motor 37 is electrically connected to the control device 52 and rotates based on a control command value output from the control device 52. Therefore, the rotation period T, the rotation range W, and the rotation range center C for rotating the laser range sensor 20 by the control device 52 can be changed.
Connected to the motor 37 is an encoder 38 that detects a rotation angle θ of the motor 37 (an angle θ (hereinafter also referred to as a vertical angle θ) (see FIG. 11) formed by a laser emitted from the laser range sensor 20 with respect to the x axis). Has been. The encoder 38 is electrically connected to the control device 52, and the vertical angle θ of the laser range sensor 20 detected by the encoder 38 is input to the control device 52.

(B-2) Configuration and Action of Laser Range Sensor 20 The laser range sensor 20 has an angle φ at which the laser is emitted (an angle φ that the laser makes with the y-axis (hereinafter also referred to as a horizontal angle φ) (see FIG. 3)). The laser is scanned while changing the angle between 0 ° and 180 °, and the distance data on the scanning surface scanned with the laser is measured. By changing the horizontal angle φ at which the laser beam is emitted by the laser range sensor 20 and simultaneously changing the vertical angle θ at which the laser beam is emitted by the rotating device 30, the laser range sensor 20 has a horizontal angle φ = 0 ° to 180 ° and a vertical angle. The laser is scanned within the rotation range of θ1 to θ2, and the distance data is measured. The angle range θ1 to θ2 for changing the laser in the vertical direction is set by the control device 14.

  FIG. 3 is a diagram schematically showing the internal structure of the laser range sensor 20. As shown in FIG. 3, the laser range sensor 20 includes a frame 22, a distance measurement unit 24 disposed in the frame 22, a mirror 25, a motor 28 that rotates the mirror 25, and an encoder that detects the rotation angle of the motor 28. 28a.

A cross section on the rear side (left side in FIG. 3) of the frame 22 is formed in a square shape, and a cross section on the front side (right side in FIG. 3) is formed in a semicircular shape around a rotation shaft 23 described later.
Shaft portions 22a and 22b are formed on side surfaces 22c and 22d of the rectangular portion of the frame 22, respectively. As described above, the shaft portions 22a and 22b are inserted into the through holes 36a and 36b of the vertical frames 35b and 35c of the rotating device 30, respectively. A side surface 22 e of the semicircular portion of the frame 22 opens over the entire surface, and the opening is closed by a resin member 27. The resin member 27 is formed of a resin material that transmits infrared light having a wavelength of approximately 900 nm well, but cuts light of other wavelengths. The resin member 27 prevents external light from entering the laser range sensor 20 and prevents malfunction of the laser range sensor 20.

  A mirror 25 is disposed in the frame 22 at a location corresponding to the center of the semicircular side surface 22e. The plate thickness of the mirror 25 is very thin, and the front and back surfaces of the mirror 25 are formed in a mirror shape. The mirror 25 is attached to the rotating shaft 23, and rotates with the rotation of the rotating shaft 23. A motor 28 is connected to the rotating shaft 23. The motor 28 rotates the mirror 25 at a preset cycle (26.4 msec in this embodiment). An encoder 28 a that detects the rotation angle of the motor 28 is attached to the motor 28. That is, the encoder 28a detects the rotation angle ψ (horizontal angle φ at which the laser is emitted) of the mirror 25. The detection resolution of the encoder 28a is 0.5 °. Therefore, the encoder 28a detects the rotation angle ψ at a timing when the rotation angle ψ of the mirror 25 becomes an integral multiple of 0.5 °. The encoder 28 a is electrically connected to the distance measuring unit 25, and the rotation angle ψ of the mirror 25 detected by the encoder 28 a is input to the distance measuring unit 25.

  A distance measuring unit 24 is arranged in the direction of ψ = 180 ° when viewed from the mirror 25. As shown in FIG. 4, the distance measuring unit 24 includes a laser light source 24a, a light receiving element 24b, an arithmetic unit 26, and a lens unit 24c, which are installed in a housing 24d.

  The laser light source 24a emits infrared laser light having a wavelength of around 900 nm. The laser light source 24a is controlled by the arithmetic unit 26 and emits laser light at a predetermined timing.

  The light receiving element 24b is disposed at a position where the laser light emitted from the laser light source 24a is not directly incident. The light receiving element 24b is a light receiving element having high sensitivity to light having a wavelength of about 900 nm, and is turned on when receiving light having a predetermined intensity or more. The light receiving element 24b is electrically connected to the arithmetic unit 26, and the output value of the light receiving element 24b is input to the arithmetic unit 26.

  A part of the side surface of the housing 24d on the mirror 25 side is opened, and the lens portion 24c is disposed in the opening. The lens unit 24c is an optical component that includes a lens, a mirror, and the like. The lens unit 24 c guides the laser beam emitted from the laser light source 24 a to the mirror 25. The light incident on the mirror 25 is reflected by the mirror 25 and irradiated outside the laser range sensor 20. The light that enters the laser range sensor 20 is reflected by the mirror 25 and guided to the lens unit 24c, and is guided from the lens unit 24d to the light receiving element 24b.

As shown in FIG. 5, a laser light source 24a, a light receiving element 24b, and an encoder 28a are electrically connected to the arithmetic unit 26. The arithmetic device 26 drives the laser light source 24a and processes signals from the light receiving element 24b and the encoder 28a. The arithmetic device 26 is further connected to the control device 52 by a USB cable 60.
The computing device 26 includes a control unit 26a, a sensing unit 26b, a counting unit 26c, a storage unit 26d, and a computing unit 26e. The count unit 26c continues to count the elapsed time since the power is turned on. The control unit 26a detects the rotation angle ψ of the mirror 25 detected by the encoder 28a, and simultaneously detects the rotation angle ψ and drives the laser light source 24a in pulses. Accordingly, the laser light is emitted in a pulsed manner from the laser light source 24a in synchronization with the detection timing of the rotation angle ψ of the encoder 28a. Further, the control unit 26a reads the time data j of the count unit 26c at the same time as the laser beam is emitted. The rotation angle ψ and time data j detected by the control unit 26a are stored in the storage unit 26d. The sensing unit 26b reads the detection signal of the light receiving element 24b. The read time data k is stored in the storage unit 26d. The calculation unit 26e calculates the laser beam irradiation angle φ, the position where the laser beam is reflected (object such as an obstacle), and the laser range from the rotation angle ψ and time data j and k stored in the storage unit 26d. A distance d between the sensors 20 is calculated (see FIG. 12).

  The operation of the laser range sensor 20 will be described with reference to FIG. When the laser range sensor 20 is activated, the motor 28 rotates and the mirror 25 rotates at a cycle of 26.4 msec. The rotation angle ψ of the mirror 25 is detected by the encoder 28a. That is, the encoder 28 a detects the rotation angle ψ at a timing when the rotation angle ψ of the mirror 25 becomes an integral multiple of 0.5 °, and inputs the rotation angle ψ to the arithmetic unit 26. Since the motor 28 rotates the mirror 25 at a period of 26.4 msec, the period at which the encoder 28a detects the rotation angle ψ is 26.4 msec / 360 / 2≈36.7 μsec. In addition, the mirror 25 is similarly formed into a mirror surface on the front and back sides, and there is no distinction between the front and back sides. Accordingly, it can be considered that the mirror 25 is in exactly the same state when the rotation angle ψ = 0 ° of the mirror 25 and when the rotation angle ψ = 180 °. Therefore, when the rotation angle detected by the encoder 28a is ψ = 180 °, the arithmetic unit 26 determines that the rotation angle ψ = 0 °.

  When the laser range sensor 20 is activated, the controller 26a first reads the rotation angle ψ of the mirror 25 detected by the encoder 28a (step S2), and determines whether or not the read rotation angle ψ is 0 ° (step S2). S4). When the rotation angle ψ is not 0 ° (NO in step S4), the control unit 26a repeatedly performs step S2 and step S4 until the rotation angle ψ becomes 0 °. On the other hand, if it is determined that the rotation angle ψ is 0 ° (YES in step S4), data M indicating that is output to the USB cable 60, and the process proceeds to step S6. The data M output to the USB cable 60 is input to the control device 52.

In step S6, the storage unit 26d stores that the current rotation angle ψ is 0 °. Almost simultaneously with storing the rotation angle ψ = 0 ° in the storage unit 26d, the control unit 26a starts pulse driving of the laser light source 24a (step S8). Thereby, a laser beam is emitted in a pulse form from the laser light source 24a.
When the laser light source 24a is driven in step S8, the control unit 26a reads the time data j counted by the counting unit 26c at the same time (step S10). The read time data j is stored in the storage unit 26d. At that time, the storage unit 26 stores the time data j in association with the rotation angle ψ stored in step S6.

Next, the control unit 26b determines whether or not the light receiving element 24b is turned on (step S12). That is, when laser light is emitted from the laser light source 24a in step S8, the laser light is emitted outside the distance measuring unit 24 through the lens portion 24d. The laser light emitted to the outside of the distance measuring unit 24 enters the mirror 25 (specifically, the vicinity of the rotating shaft 23 (hereinafter referred to as the laser origin 23a)) from the direction of ψ = 180 °. The laser light incident on the mirror 25 is reflected so that the incident angle with respect to the mirror 25 and the emission angle from the mirror 25 are equal. As described above, the distance measuring unit 24 is fixed. On the other hand, the mirror 25 rotates around the rotation shaft 23. Therefore, the reflection direction of the laser light reflected by the mirror 25 is determined by the rotation angle ψ of the mirror 25. When the reflection direction of the laser beam reflected by the mirror 25 is represented by an angle φ in FIG. 3, φ = 2ψ is established.
As is clear from the above calculation formula, when the mirror rotation angle ψ is 0 ° to 90 °, the laser emission angle φ is 0 ° to 180 °. When the rotation angle ψ is 90 ° to 180 °, the laser is not emitted from the laser light source 24a according to the determination in step S4. Accordingly, the laser light emitted from the laser light source 24a is reflected in a direction where the angle φ = 0 ° to 180 °.

  The laser beam reflected by the laser origin 23 a of the mirror 25 enters the resin member 27. As described above, the resin member 27 is formed in a semicircular shape around the rotation axis 23 of the mirror 25 and transmits light having a wavelength of about 900 nm. Therefore, the laser beam reflected by the laser origin 23a is incident on the resin member 27 perpendicularly, passes through the resin member 27, and is emitted to the outside. That is, laser light is emitted from the laser range sensor 20 in the direction of the horizontal angle φ.

  If an object is present in the direction in which the laser beam is emitted from the laser range sensor 20, the object is irradiated with the laser beam, and the object causes irregular reflection of the laser beam. Part of the irregularly reflected laser light returns into the laser range sensor 20 and is reflected by the mirror 25, and is guided to the light receiving element 24b via the lens portion 24c of the distance measuring unit 24. Since the light guided to the light receiving element 24b is light obtained by irregularly reflecting the laser light from the laser light source 24a, the wavelength thereof is around 900 nm. Since the light receiving element 24b is highly sensitive to light having a wavelength of about 900 nm, the light receiving element 24b is turned on when receiving the irregularly reflected laser light. On the other hand, if there is no object in the direction in which the laser beam is emitted from the laser range sensor 20, the laser beam is not irregularly reflected by the object, and the light receiving element 24b is not turned on. Accordingly, in step S12, the control unit 26a determines whether or not the light receiving element 24b is turned on.

When the light receiving element 24b is turned on (that is, when the sensing unit 26b detects the output signal of the light receiving element 24b (YES in step S12)), the control unit 26a counts at the same time as detecting that the light receiving element 24b is turned on. The time data k counted by the unit 26c is read, and the read time data k is stored in the storage unit 26d (step S14). At that time, the storage unit 26d stores the read time data k in association with the rotation angle ψ stored in step S6. That is, the storage unit 26d stores the distance data A composed of the rotation angle ψ, the time data j, and the time data k.
When the light receiving element 24b is not ON (NO in step S12), the control unit 26a performs a predetermined time t (the period in which the encoder 28a detects the rotation angle ψ) after the execution of step S8. It is determined whether or not a time shorter than 7 μsec has elapsed (step S16). If the predetermined time has not elapsed (NO in step S16), the process returns to step S12 and the processes from step S12 are repeated. On the other hand, when the predetermined time has elapsed (YES in step S16), the control unit 26a determines that there is no object in the direction in which the laser beam is emitted, and stores the time data j stored in step S10 from the storage unit 26d. The distance data A for the rotation angle ψ of the mirror 25 stored in step S6 is set to L (= detection limit distance of the laser range sensor 20) stored in step S6 (step S18).

  In step S20, the control unit 26a waits until the encoder 28a detects the rotation angle ψ of the mirror 25 again. When the encoder 28a detects the rotation angle ψ, the control unit 26a reads the rotation angle ψ (step S20). ). Next, the control unit 26a determines whether or not the rotation angle ψ read in Step S20 is 90.5 ° (Step S22). When the rotation angle ψ is not 90.5 ° (NO in step S22), the process returns to step S6 and the processing from step S6 is executed. As a result, the distance data A for the rotation angle ψ read in step S20 is stored in the storage unit 26d.

  As described above, steps S6 to S22 are repeatedly executed by the arithmetic unit 26 until the rotation angle ψ = 90.5 °. The above-described processing is executed at a pitch of 0.5 ° between the rotation angles ψ = 0 ° and ψ = 90 °. As described above, the rotation angle ψ of the mirror 25 and the laser beam emission angle φ have a relationship of φ = 2ψ. Accordingly, the laser light is emitted from the laser range sensor 20 at a pitch of 1 ° between φ = 0 ° and 180 °, and the distance data A is measured each time.

When the rotation angle ψ = 90.5 ° (YES in step S22), the calculation unit 26e emits a laser from the laser range sensor 20 using each distance data A stored in the storage unit 26d. The horizontal angle φ and the distance d from the laser range sensor 20 to the object irradiated with the laser light are calculated (step S24). That is, as described above, the angle φ is obtained by φ = 2ψ. The distance d is obtained by the time difference between the time data j and the time data k (specifically, d = (k−j) / c (= speed of light)).
The calculation unit 26e performs the above calculation on all the distance data A stored in the storage unit 26d, and converts it into distance data B configured by the angle φ and the distance d. The converted distance data B is stored in the storage unit 26d.

  In step S26, all the distance data B converted in step S24 are output to the control device 52 via the USB cable 60 (step S26). When the distance data B is transferred to the control device 52, the calculation unit 26e deletes each distance data A and each distance data B stored in the storage unit 26d (step S28).

  The mirror 25 is rotated by the motor 28 while steps S24 to S28 are being executed. The processes in steps S24 to S28 are executed and finished after the mirror 25 reaches the rotation angle ψ = 90.5 ° to ψ = 180 ° (that is, ψ = 0 °). Even after step S28 is completed, the mirror 25 is rotated. During this time, the control unit 26a detects the rotation angle ψ of the mirror 25 by the encoder 28a (step S30), and whether the rotation angle ψ of the mirror 25 has reached 180 °. It is determined whether or not (step S32). When the rotation angle ψ of the mirror 25 does not become 180 ° (NO in step S32), the process returns to step S30, and when the rotation angle ψ of the mirror 25 becomes 180 ° (YES in step S32), the control unit 26a sets ψ = 180 ° is set to ψ = 0 ° (step S33), the process returns to step S6, and the processing from step S6 is executed again. In step S32, as in step S4, when ψ = 0 °, the control unit 26a outputs data M indicating that to the control device 52 via the USB cable 60.

  As is apparent from the above description, the laser range sensor 20 repeatedly executes steps S6 to S22 during a period in which the rotation angle ψ of the mirror 25 is 0 ° to 90 °. As a result, laser light is emitted from the laser origin 23a in the direction of the horizontal angle φ = 0 ° to 180 °, and the distance data A is measured. Further, steps S24 to S26 are executed during a period in which the rotation angle ψ of the mirror 25 is 90 ° to 180 °, the distance data B is calculated, and each distance data B is transferred to the control device 52. When the laser range sensor 20 repeatedly executes the measurement of the distance data A, the calculation of the distance data B, and the transfer of the distance data B, the distance data B is transferred to the control device 52 at a predetermined cycle.

  Further, the laser range sensor 20 is rotated in the vertical direction by the rotating device 30 while the distance data is being measured. The vertical angle θ at which the laser range sensor 20 emits a laser is changed by being rotated by the rotating device 30. Accordingly, the laser range sensor 20 measures the distance data within the range of the horizontal angle φ = 0 ° to 180 ° while changing the vertical angle θ. Therefore, the measurement range of the laser range sensor 20 can be changed by changing the rotation range of the vertical angle θ by the rotation device 30.

(B-3) Configuration of Control Device 52 The control device 52 is configured by a microprocessor or the like including a CPU, a ROM, and a RAM. The control device 52 is connected to the laser range sensor 20 by the USB cable 60 and is electrically connected to the rotation device 30 and the control device 14.
As shown in FIG. 2, the control device 52 includes a calculation unit 52 a that calculates three-dimensional distance data using the distance data B input from the laser range sensor 20, and a rotation control unit 52 b that controls the rotation device 30. The storage unit 52c stores the distance data input from the laser range sensor 20.

  The rotation control unit 52 b generates a rotation trajectory based on the rotation angle range W, the rotation center C, and the rotation period T set by the control device 14 of the autonomous mobile body 16. Further, the rotation control unit 52b outputs a control command value to the rotating device 30 based on the generated rotation trajectory. Thereby, the rotating device 30 rotates the laser range sensor 20 on the generated rotation trajectory.

The rotation control unit 52 b calculates the upper maximum angle and the lower maximum angle based on the rotation angle range W, the rotation center C, and the rotation period T set by the control device 14. The upper maximum angle is obtained by C + W. The maximum downward angle is obtained by C-W. Then, the obtained upper maximum angle and lower maximum angle are arranged at a period of T with respect to the time axis to generate a rotation trajectory. Specifically, a predetermined period before and after the timing at which the upper maximum angle and the lower maximum angle are reached is a gradual change period D, and in the gradual change period D, the rotational angular velocity dθ / dt is changed at a constant rotational angular acceleration. Is a constant angular velocity period E, and in the constant angular velocity period E, the rotational trajectory is generated so that the rotational angular velocity dθ / dt is a constant angular velocity.
7 and 8 are examples of the rotation trajectory of the laser range sensor 20 generated by the rotation control unit 52b. FIG. 7 shows the rotation trajectory when the rotation angle range W = W ₁ , the rotation center C = 0, and the rotation cycle T = T ₁ . In the rotation trajectory shown in FIG. 7, the upper maximum angle is 0 + W ₁ = W ₁ and the lower maximum angle is 0−W ₁ = −W ₁ . In the gradual change period D, the rotational angular velocity changes at a constant rotational angular acceleration, and in the constant angular velocity period E, the rotational angular velocity is dθ ₁ / dt (= constant).
FIG. 8 shows the rotation trajectory when the rotation angle range W = W ₂ , the rotation center C = −W ₂ , and the rotation period T = T ₂ . In the rotation trajectory shown in FIG. 8, the maximum upper angle is −W ₂ + W ₂ = 0 and the maximum downward angle is −W ₂ −W ₂ = −2W ₂ . In the transformation period D, the rotational angular velocity changes with a constant rotational angular acceleration, and in the constant angular velocity period E, the rotational angular velocity is dθ ₂ / dt.

When the rotation control unit 52b generates a rotation trajectory, the rotation control unit 52b outputs a control command value to the rotation device 30 based on the rotation activation. Therefore, the rotating device 30 rotates the laser range sensor 20 along the rotation trajectory. As described above, the laser range sensor 20 emits a laser in the direction of the vertical angle θ. Accordingly, the laser range sensor 20 scans the laser beam between the upper maximum angle and the lower maximum angle. That is, the angle range between the upper maximum angle and the lower maximum angle is the measurement range of the laser range sensor 20.
When the angular velocity dθ / dt at which the laser range sensor 20 rotates is changed, the angular pitch in the angle θ direction at which the laser range sensor 20 emits laser light is changed. The angular pitch at which the laser range sensor 20 emits laser light is the density of measurement points of distance data (that is, measurement resolution). That is, by setting the rotation angle range W, the rotation center C, and the rotation period T, the rotation angular velocity dθ / dt of the laser range sensor 20 is changed, and thereby the measurement resolution of the laser range sensor 20 can be changed. .
Further, in the constant angular velocity period E, the rotation control unit 52b rotates the laser range sensor 20 so that the rotational angular velocity dθ / dt becomes a constant angular velocity. Therefore, distance data can be measured with a constant resolution within a predetermined angle range from the rotation range center C.

  Note that the rotation angle range W, the rotation center C, and the rotation period T described above are set by the control device 14 based on the moving speed of the autonomous mobile device 10. That is, the control device 14 of the autonomous mobile body 16 calculates the moving speed of the autonomous mobile body 16 based on the detection results detected by the encoders 48a to 48d. Then, the rotation angle range W, the rotation center C, and the rotation period T are set based on the calculated moving speed. Thereby, the rotation control part 52b produces | generates the rotation track | orbit according to the moving speed of the autonomous mobile body 16, and rotates the laser range sensor 20 based on the rotation track | orbit.

In this embodiment, when the moving speed of the autonomous mobile body 16 is fast, the rotation angle range W is set narrow, and when the moving speed is slow, the rotation angle range W is set wide. Thereby, when the moving speed of the autonomous mobile body 16 is slow, distance data in a wide angle range is measured, and when the moving speed of the autonomous mobile body 16 is fast, only distance data in the minimum necessary range is measured. .
Further, when the moving speed of the autonomous mobile body 16 is fast, the rotation center C is set in the downward direction (that is, the road surface direction), and when it is slow, it is set in the front direction. Thereby, when the moving speed of the autonomous mobile device 10 is fast, distance data on the road surface on which the autonomous mobile body 16 travels is mainly measured.
Moreover, when the moving speed of the autonomous mobile body 16 is fast, the rotation period T is set short, and when the moving speed is slow, it is set long. That is, when the moving speed of the autonomous mobile body 16 is fast, the rotational angular speed dθ / dt increases, and when the moving speed of the autonomous mobile body 16 is slow, the rotational angular speed dθ / dt decreases. Thereby, when the moving speed of the autonomous mobile body 16 is fast, an obstacle can be detected earlier.

7 described above is a rotation trajectory when the movement speed of the autonomous mobile body 16 is low, and FIG. 8 is a rotation trajectory when the movement speed of the autonomous mobile body 16 is high. Figure 7, a comparison of FIG. 8, the rotation angle range W ₁ in FIG. 7 is set larger than the rotation range W ₂ in FIG. 8. Therefore, a wider range of distance data is measured on the rotating trajectory of FIG. In FIG. 7, the rotation center C = 0, whereas in FIG. 8, the rotation center C = −W. Therefore, the rotation trajectory of FIG. 8 is measured around the floor surface. The rotation period T2 of FIG. 8 is set to be shorter than the rotation range T ₁ of the FIG. Therefore, an obstacle can be detected more quickly in the rotation trajectory of FIG.

  The calculation unit 52a calculates three-dimensional distance data by calculating the three-dimensional distance data from the position and traveling direction of the autonomous mobile body 16 input from the control device 14, the distance data B stored in the storage unit 52c, and the vertical angle θ. Generate a map. The three-dimensional map calculated by the calculation unit 52a is output to the control device 14.

The operation of the calculation unit 52a will be described with reference to FIGS. As shown in FIG. 10, the autonomous mobile device 10 is activated in a state where it is placed on a horizontal plane. A position A in FIG. 10 is a position when the autonomous mobile device 10 is activated.
As shown in FIG. 9, when the autonomous mobile device 10 is activated, first, the calculation unit 52a sets the origin (step S34). That is, the calculation unit 52a sets the starting position (position A in FIG. 10) as the origin (more specifically, sets the midpoint 34 (reference point 34) on the rotation shaft 32 of the autonomous mobile device 10 as the origin. To do). The computing unit 52a sets an xyz coordinate system in which the front direction of the autonomous mobile device 10 at the time of activation is the x axis, the vertical direction is the z axis, and the direction orthogonal to the x axis and the z axis is the y axis.

  When the autonomous mobile device 10 is activated, the laser range sensor 20 starts to acquire distance data, and the laser range sensor 20 is rotated by the rotating device 30. As described above, the laser range sensor 20 outputs data M (that is, data indicating that the rotation angle ψ of the mirror 25 of the laser range sensor 20 is 0 °) to the calculation unit 52a via the USB cable 60. (Step S36).

  When the data M is input to the calculation unit 52a, the calculation unit 52a reads the vertical angle θ detected by the rotating device 30 (step S38). The vertical angle θ is read almost simultaneously with the input of the data M. Therefore, the vertical angle θ read by the calculation unit 52a is the vertical angle θ when the laser range sensor 20 emits the laser in the direction of φ = 0 °.

  Moreover, the calculating part 52a reads the position (a, b) and direction V of the autonomous mobile device 10 from the control device 14 of the autonomous mobile body 16 (step S42). As already described, the position (a, b) is calculated with reference to the reference point 34 and is represented by the x and y coordinates in the above-described xyz coordinate system, and the direction V is represented by the angle R with respect to the x axis. ing. The position (a, b) and the angle R read in step S42 are those when the laser range sensor 20 emits a laser in the direction of φ = 0 °.

  As described above, when the laser range sensor 20 outputs the data M, the laser range sensor 20 scans the laser beam between φ = 0 ° and 180 °, and acquires the distance data A at each emission angle φ. And after acquiring all the distance data A in φ = 0 ° to 180 °, the distance data B is calculated from each distance data A. When the laser range sensor 20 calculates each distance data B, it outputs the distance data B to the control device 52 via the USB cable 60. Each distance data B input to the control device 52 is input to the storage unit 52c (step S44).

  When each distance data B is input to the storage unit 52c, the calculation unit 52a calculates three-dimensional distance data based on the distance data B, the position (a, b), the angle R, and the vertical angle θ. Do. Below, the calculation method of three-dimensional distance data is demonstrated.

  In step S46, the calculation unit 52a selects one distance data B to be calculated from each distance data B stored in the storage unit 52c. At this time, the calculation unit 52a selects the distance data B having the smallest emission angle φ from the distance data B stored in the storage unit 52c.

In step S48, the vertical angle θ is corrected based on the emission angle φ of the distance data B selected in step S46. That is, the vertical angle θ read by the calculation unit 52a in step S38 is the vertical angle θ when the emission angle φ = 0 °. The laser range sensor 20 is rotated by the rotating device 30 while the laser beam is scanned from φ = 0 ° to φ = 180 °, and the vertical angle θ is changed. Therefore, if the distance data B other than φ = 0 ° is calculated using the vertical angle θ, an error occurs in the calculation result. Therefore, the vertical angle θ is corrected. The correction of the vertical angle θ is performed by the following calculation formula.
θ ′ = θ + (dθ / dt) · td
Here, θ ′ is a corrected vertical angle, dθ / dt is an angular velocity at which the laser range sensor 20 rotates when θ is detected, td is a time when the vertical angle θ is read, and distance data B Is the time difference from the detected time. In the present embodiment, since the laser range sensor 20 scans the laser beam in the section of φ = 0 ° to 180 ° is 6.6 msec, td = φ / 180 × 6.6.
The position (a, b) and the angle R read by the calculation unit 52a in step S42 are also data when the emission angle φ = 0 °. Therefore, the position (a, b) and the angle R may be corrected. However, in this embodiment, since the moving speed of the autonomous mobile device 10 is slow and the amount of movement of the autonomous mobile device 10 during the period in which the laser range sensor 20 measures distance data is small, the position (a, b) and Even if the angle R is not corrected, an error hardly occurs. Therefore, in this embodiment, the position (a, b) and the angle R are not corrected.

When correcting the vertical angle θ, the calculation unit 52a calculates the relative position of the object irradiated with the laser light emitted from the laser range sensor 20 with respect to the autonomous mobile device 10 (step S50).
The relative position is calculated by calculating the distance data B (that is, the emission angle φ and the distance d) and the corrected vertical angle θ ′. The relative position is based on the reference point 34 at the current position of the autonomous mobile device 10 (position B in FIG. 10), the current traveling direction of the autonomous mobile device 10 is the x ′ axis, the vertical direction is the z ′ axis, It is represented by an x′y′z ′ coordinate system in which the direction orthogonal to the x ′ axis and the z ′ axis is the y ′ axis.
The relative coordinates (x ′, y ′, z ′) are obtained by the sum of the offset vector O between the reference point 34 and the laser origin 23a shown in FIGS. 11 and 12 and the vector L indicating the laser oscillation trajectory. The parameters (x ′ _o , y ′ _o , z ′ _o ) of the offset vector O are constants x ′ _o1 and z ′ _o1 (see FIG. 11) determined by the mounting dimensions of the laser range sensor 20 and the rotating device 30 and the vertical angle. It can be obtained by θ ′. That is,

Α is an angle formed by the offset vector O and the vector L.
Further, the parameters (x ′ _L , y ′ _L , z ′ _L ) of the vector L can be obtained from the distance d, the emission angle φ, and the vertical angle θ ′. That is,

  Accordingly, the relative coordinates (x ′, y ′, z ′) of the object irradiated with the laser with respect to the autonomous mobile device 10 are as follows.

  When the arithmetic unit 52a calculates the relative coordinates (x ′, y ′, z ′), the absolute coordinates (x in the xyz coordinate system of the object irradiated with the laser are calculated from the relative coordinates (x ′, y ′, z ′). , Y, z) is calculated (step S52). The absolute coordinates (x, y, z) are three-dimensional distance data indicating the absolute position of the object irradiated with the laser. The coordinates (x, y, z) are the angles formed by the coordinates (x ′, y ′, z ′) and the position (a, b) of the autonomous mobile device 10 and the traveling direction V of the autonomous mobile device 10 and the x axis. It is obtained by converting the coordinates using R. That is,

When calculating the three-dimensional distance data (x, y, z), the computing unit 52a plots the calculated three-dimensional distance data (x, y, z) on the xyz coordinates set in step S34 (step S54). When the three-dimensional distance data (x, y, z) is plotted, the calculation unit 52a deletes the distance data B selected in step S46 from the storage unit 52c (step S56). When the distance data B is deleted from the storage unit 52c, the calculation unit 52a determines whether or not the distance data B exists in the storage unit 52c (step S58).
If the distance data B exists in the storage unit 52c (YES in step S58), the process returns to step S46 and the processing from step S46 is executed. Thereby, three-dimensional distance data (x, y, z) is calculated for all the distance data B. On the other hand, when the distance data B does not exist in the storage unit 52c (NO in step S58), the calculation unit 52a outputs the plotted three-dimensional map to the control device 14 (step 60), and returns to step S36. The process from step S36 is executed.

Through the above processing, the three-dimensional distance data (x, y, z) is calculated from all the distance data B stored in the storage unit 52c. Each calculated three-dimensional distance data (x, y, z) is plotted in xyz coordinates in step S54. As a result, a three-dimensional map representing the shape of the xyz space is created.
In the processes of steps S46 to S60, after the laser range sensor 20 outputs each distance data B to the USB cable 60 (step S26 in FIG. 6), the next measurement period starts (that is, in FIG. 6). This is executed until the output of data M in step S32. Therefore, the data M is not input from the laser range sensor 20 to the calculation unit 52a while the calculation unit 52a executes steps S46 to S60.
In addition, the calculation unit 52a rotates the laser range sensor 20 with the time td calculated using the time (in this embodiment, 6.6 msec) that the laser range sensor 20 scans the light beam on one scanning plane. The vertical angle θ input from the rotating device 30 is corrected using the angular velocity dθ / dt. Therefore, accurate three-dimensional distance data can be obtained.

Next, processing in which the control device 14 controls the moving direction and moving speed of the autonomous mobile device 10 will be described with reference to FIG.
When starting the autonomous mobile device 10, first, the destination is input to the control device 14 (step S62). The destination is specified by xy coordinate values in the absolute coordinate system. When the destination is input, the three-dimensional measuring device 18 is activated and starts measuring three-dimensional distance data.

  When the three-dimensional measuring device 18 starts measuring the three-dimensional distance data, a three-dimensional map is output from the three-dimensional measuring device 18, and the three-dimensional map is input to the control device 14 (step S64). The control device 14 determines whether or not there is an obstacle (position of the obstacle) in the traveling direction determined from the current position of the autonomous mobile device 10 and the position of the destination from the input three-dimensional map (step). S66).

If it is determined that there is no obstacle in the destination direction (NO in step S66), the control device 14 outputs a control command value to the motors 46a to 46d, and moves the autonomous mobile device 10 in the direction of the destination (step S68). ). On the other hand, if it is determined that there is an obstacle in the destination direction (NO in step S66), the control device 14 changes the traveling direction of the autonomous mobile device 10 in a direction to avoid the obstacle, and in the changed traveling direction. A control command value is output to the motors 46a to 46d so that the self-moving device 10 moves (step S70).
In addition, when there is no obstacle in the moving direction of the autonomous mobile device 10, the control device 14 accelerates the moving speed of the autonomous mobile device 10 to a predetermined speed. That is, when there is no obstacle in the moving direction of the autonomous mobile device 10, the autonomous moving device 10 does not change the moving direction, and thus the three-dimensional distance data in the moving direction is sufficiently obtained. Therefore, even if the moving speed is accelerated, the moving device 10 can move without colliding with an obstacle.

  When the control device 14 moves the autonomous mobile device 10 in step S68 or step S70, the control device 14 determines whether or not the autonomous mobile device 10 has arrived at the destination (step S74). If it determines with the autonomous mobile apparatus 10 not having arrived at the destination (it is NO at step S74), it will return to step S64 and will perform the process from step S64. If it is determined that the autonomous mobile device 10 has arrived at the destination (YES in step S74), the movement of the autonomous mobile device 10 is stopped. Thereby, the autonomous mobile device 10 can move to the destination while avoiding the obstacle.

As is clear from the above description, the autonomous mobile device 10 of the present embodiment sets the rotation cycle T and the rotation angle range W of the rotation device 30 by the control device 14, and the rotation cycle T set by the rotation control unit 52b. The rotation device 30 is driven in the rotation angle range W. Therefore, the resolution and measurement range of distance data measurement by the laser range sensor 20 can be arbitrarily changed.
Further, in the autonomous mobile device 10 of the present embodiment, the rotation control unit 52b generates a rotation trajectory of the laser range sensor 20 so that the rotation control unit 52b rotates at a constant angular velocity within a predetermined angle range from the rotation center C. Therefore, within a predetermined angle range from the rotation center C, distance data can be measured with uniform resolution.
Further, in the autonomous mobile device 10 of the present embodiment, the calculation unit 52a calculates the time td calculated using the time (6.6 msec) that the laser beam scans one scanning surface by the laser range sensor 20, and the rotating device 30 is a laser. The vertical angle θ input from the rotating device 30 is corrected using the angular velocity dθ / dt that rotates the range sensor 20. Therefore, the shift in the data acquisition timing is corrected, and the three-dimensional distance data can be accurately calculated.
Moreover, in the autonomous mobile device 10 of the present embodiment, the calculation unit 52a corrects the measured three-dimensional distance data using the movement amount (that is, the position (a, b) and the angle R) of the autonomous mobile device 10. To do. Accordingly, the measured three-dimensional distance data can be converted into coordinate values in the xyz coordinate system (absolute coordinate system), and the autonomous mobile device 10 moves while avoiding obstacles to the destination specified in the absolute coordinate system. can do.

In the autonomous mobile device 10 according to the present embodiment, the rotation period T, the rotation angle range W, and the rotation center C for rotating the laser range sensor 20 are set according to the moving speed of the autonomous mobile device 10. It is not restricted to such embodiment, A rotation track can also be set by another method.
For example, the autonomous mobile device 10 is further provided with a gyro sensor that detects the tilt angle of the autonomous mobile body 16 with respect to the vertical axis, and the rotation center C and / or the rotation angle range W is corrected based on the tilt angle detected by the gyro sensor. It is good also as composition to do. According to such a configuration, even when the autonomous mobile device 10 is tilted with respect to the vertical axis, the rotation center C and / or the rotation angle that rotates the laser range sensor 20 based on the tilt angle detected by the gyro sensor. Range W is modified. Thereby, the autonomous mobile device 10 can measure the three-dimensional distance data in the measurement range according to the road surface inclination state. For example, by correcting the rotation center C based on the inclination angle detected by the gyro sensor, the three-dimensional distance data can be measured in the same measurement range as when the road surface is not inclined. When the vehicle 10 travels on an uneven road surface, the rotation center C may be set in the road surface direction (that is, the minus side). According to such a configuration, the measurement range of the laser range sensor 20 is set with the road surface as the center, so that unevenness on the road surface can be suitably detected.
Further, when the autonomous mobile device 10 moves in an indoor environment, the rotation center C may be set in the ceiling direction (that is, the plus side). According to such a configuration, the absolute position of the autonomous mobile device 10 can be accurately identified by the laser range sensor 20 measuring the three-dimensional distance data of the ceiling.
Moreover, it is good also as a structure which starts the laser range sensor 20 without rotating at normal time, and rotates the laser range sensor 20 when an obstacle is detected by the laser range sensor 20. Accordingly, in a situation where no obstacle is detected, distance data in the traveling direction is measured in a short cycle, and only when the obstacle is detected, the laser range sensor 20 is rotated by the rotating device and the shape of the obstacle is measured. be able to.
In the above-described embodiment, when correcting the vertical angle θ, the time td is calculated by a calculation formula. However, the time td may be obtained by performing an experiment. By obtaining the time td experimentally, the vertical angle θ can be corrected more accurately.
In the above-described embodiment, the position and moving direction of the autonomous mobile device 10 are calculated from the wheel rotation amounts o, p, q, and r detected by the encoders 48a to 48d. The present invention is not limited to such an embodiment. For example, the position and moving direction of the autonomous mobile device 10 may be detected using GPS (Global Positioning System).
In the autonomous mobile device 10 described above, the rotation trajectory is generated by setting the rotation angle range W, the rotation center C, and the rotation period T, but the present invention is not limited to such an embodiment. For example, the rotation trajectory may be generated by setting the upper maximum angle, the lower maximum angle, and the rotational angular velocity dθ / dt.
Furthermore, in the above-described embodiment, the rotation angle range W, the rotation center C, and the rotation cycle T are set by the control device 14 of the autonomous mobile body 16, but the rotation angle range W, the rotation center C, and the rotation cycle T are set to 3. You may make it carry out by the input device etc. which were provided in the dimension measuring apparatus 18 separately.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The perspective view of the autonomous mobile apparatus 10 of a present Example. The block diagram which shows the structure of the autonomous mobile apparatus 10 of a present Example. The internal structure figure of the laser range sensor 20 of a present Example. The enlarged view of the distance measurement unit 24. FIG. The block diagram of the arithmetic unit 26. FIG. The flowchart which shows the process of the arithmetic unit 26. The graph which shows the trajectory of the swing motion of the laser range sensor. The graph which shows the trajectory of the swing motion of the laser range sensor. The flowchart which shows the process of the calculating part 52a. The perspective view which shows the motion of the autonomous mobile apparatus 10 of a present Example. The side view of the laser range sensor 20. FIG. The top view of the laser range sensor 20. FIG. The flowchart which shows the process of the control apparatus.

Explanation of symbols

10: autonomous mobile device 14: control device 16: autonomous mobile body 18: three-dimensional measuring device 20: laser range sensor 23: rotating shaft 23a: laser origin 24: distance measuring unit 24a: laser light source 24b: light receiving element 24c: lens unit 25: Mirror 26: Computing device 26a: Control unit 26b: Sensing unit 26c: Count unit 26d: Storage unit 26e: Computing unit 28: Motor 28a: Encoder 30: Rotating device 32: Rotating shaft 34: Reference point 37: Motor 38: Encoder 40: Four-wheel bogie 42: Bogie main body 44a to 44d: Wheels 46a to 46d: Motors 48a to 48d: Encoder 52: Control device 52a: Calculation unit 52b: Rotation control unit 52c: Storage unit

Claims (8)

A three-dimensional measuring apparatus for measuring a three-dimensional shape of space,
A distance measuring device that measures distance data on a scanning plane scanned by a light beam by scanning the light beam around a scanning axis;
A rotation device mounted with a distance measurement device and rotating the distance measurement device around a rotation axis not parallel to the scanning axis;
A sensor for detecting the rotation angle of the rotating device;
An arithmetic device for calculating three-dimensional distance data using distance data input from a distance measuring device and a rotation angle input from a sensor;
Setting means for setting a rotation period and / or a rotation angle range of the rotation device;
And a rotation control device that drives the rotation device within a set rotation period and / or rotation angle range.   The three-dimensional measurement apparatus according to claim 1, wherein the rotation control device drives the rotation device based on a rotation trajectory calculated using the set rotation period and / or rotation angle range.   The three-dimensional measuring apparatus according to claim 2, wherein the calculated rotation trajectory has a constant angular velocity within a predetermined angle range from the center of the set rotation angle range.   The computing device calculates the three-dimensional distance data by correcting the rotation angle input from the sensor, using the time when the light beam scans one scanning plane by the distance measuring device and the angular velocity of the rotating device. Item 4. The three-dimensional measuring apparatus according to item 3. It is an autonomous mobile device that moves to the target point while avoiding obstacles,
A distance measuring device that measures distance data on a scanning plane scanned by a light beam by scanning the light beam around a scanning axis;
A rotation device mounted with a distance measurement device and rotating the distance measurement device around a rotation axis not parallel to the scanning axis;
A moving body on which a rotating device is mounted;
A sensor for detecting the rotation angle of the rotating device;
An arithmetic device for calculating three-dimensional distance data using distance data input from a distance measuring device and a rotation angle input from a sensor;
A moving body control device that controls the moving direction and moving speed of the moving body using the three-dimensional distance data calculated by the calculation device;
Setting means for setting a rotation period and / or a rotation angle range of the rotation device;
An autonomous mobile device comprising: a rotation control device that drives the rotation device within a set rotation period and / or rotation angle range.   6. The autonomous mobile device according to claim 5, wherein the setting means sets the rotation cycle of the rotating device according to the moving speed of the moving body.   The autonomous mobile device according to claim 5 or 6, wherein the arithmetic device corrects the three-dimensional distance data using the moving amount of the moving body.   The rotation control device further includes a sensor for detecting an inclination angle with respect to the vertical axis of the moving body, and the rotation control device corrects a rotation angle range for rotating the distance measuring device based on the inclination angle detected by the sensor. The autonomous mobile device according to any one of 5 to 7.

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