JP4848871B2 - Autonomous mobile device - Google Patents

Description

  The present invention relates to an autonomous mobile device that moves to a target point while avoiding an obstacle.

A three-dimensional measuring apparatus that measures the shape of a space in three dimensions is known. The three-dimensional measuring device includes a distance measuring device that measures distance data on a scanning line scanned with a light beam by scanning the light beam around a scanning axis, and a distance measuring device that is fixed around a rotation axis orthogonal to the scanning axis. A rotation device that rotates at an angular velocity, 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 device measures two-dimensional distance data represented by an angle around a scanning axis irradiated with a light beam and a distance to an 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, the rotation angle around the rotation axis by the rotation device (that is, the 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.
Patent Document 1 discloses a technique for measuring a three-dimensional shape of a space using a distance measuring device that measures distance data on a scanning line scanned with a light beam by scanning the light beam around a scanning axis. Yes. In the technique of Patent Document 1, a distance measuring device is installed on a railway vehicle, two-dimensional distance data is measured by the distance measuring device, and a three-dimensional shape of a space is measured by moving the railway vehicle.

JP 2005-69700 A

An autonomous mobile device equipped with this type of three-dimensional measuring device is known. Such an autonomous mobile device may measure a three-dimensional shape such as a floor surface in the traveling direction of the autonomous mobile device. For example, the autonomous mobile device can detect an obstacle in the traveling direction by measuring the floor surface shape in the traveling direction, and can safely move the floor surface.
On the other hand, in the autonomous mobile device, the distance measuring device is usually rotated at a constant angular velocity around a rotation axis that is orthogonal to the scanning axis and the traveling direction of the autonomous mobile device. In this way, when the distance measuring device is rotated around the rotation axis at a constant angular velocity and the shape of the plane is measured, the distance at which the light beam is scanned becomes wider at a position far from the distance measuring device on the plane, and the measurement resolution is reduced. descend. For this reason, the obstacle in the position far from the autonomous mobile device cannot be detected at an early stage. Thus, the conventional autonomous mobile device has a problem that the resolution is lowered when measuring the shape of the position far from the distance measuring device on the plane.

  The present invention has been made in view of the above circumstances, and provides an autonomous mobile device that can suppress a decrease in resolution even when measuring the shape of a position far from the distance measuring device on the measurement surface. With the goal.

The autonomous mobile device of the present invention includes a distance measuring device that measures distance data on a scanning line scanned with a light beam by scanning the light beam around a scanning axis at a predetermined period, and a distance measuring device attached to the distance measuring device. Input from a distance measuring device, a rotating device that rotates around a rotation axis that is orthogonal to the scanning axis and the traveling direction of the autonomous moving device, a moving body on which the rotating device is mounted, a sensor that detects the rotation angle of the rotating device, An arithmetic device that calculates three-dimensional distance data using the distance data and a rotation angle input from the sensor, a rotation control device that controls the rotational motion around the rotation axis of the rotating device, and
And 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. When the rotation control device scans the light beam from the distance measurement device toward the reference plane, when scanning the light beam at a position far from the distance measurement device on the reference plane, the distance measurement device on the reference plane. The rotating device is rotated at an angular velocity slower than that when scanning a light beam at a position close to the position.
In this autonomous mobile device, when the rotation control device scans the light beam at a position far from the distance measuring device on the reference plane, it is slower than when the light beam is scanned at a position near the distance measuring device on the reference plane. The rotating device is rotated at an angular velocity. Therefore, as compared with the case where the rotating device is rotated at a constant angular velocity, when the light beam is scanned at a position far from the distance measuring device on the reference plane, the interval at which the light beam is scanned is suppressed, Reduction in resolution can be suppressed.
Here, the “reference plane” refers to a plane set as a target whose shape is measured by the autonomous mobile device. Therefore, the plane set as the measurement target may be different from the plane actually measured. For example, when the autonomous mobile device is set to measure the shape of a horizontal floor surface, the floor surface actually measured by the autonomous mobile device may be inclined. In this case, depending on the shape of the plane in which the rotation control device is actually measured, as the distance from the distance measuring device increases, the interval at which the light beam is scanned may become wider (or narrower). As a method for setting the “reference plane”, a plane measured by rotating the rotating device around the rotation axis at an equal angular velocity may be set as the “reference plane”. For example, when measuring an inclined floor surface by an autonomous mobile device, first, measure the floor surface by rotating the rotating device around the rotation axis at an equiangular velocity, and calculate the inclination angle of the floor surface from the measurement result. A floor surface inclined at the calculated inclination angle is defined as a “reference plane”.

In the autonomous mobile device described above, the rotation trajectory of the rotation control device is determined so that the rotation angular velocity of the rotation device becomes slower as the distance from the distance measurement device to the position where the light beam on the reference plane is scanned becomes longer. It is preferable.
According to such a configuration, since the rotational speed is controlled according to the distance from the distance measuring device to the position where the light beam on the reference plane is scanned, it is possible to appropriately scan the light beam on the reference plane.

In the above-described autonomous mobile device, it is preferable that the rotation control device controls the rotary device using a plane corresponding to a floor surface on which the autonomous mobile device moves as a reference plane.
According to such a configuration, since the floor shape on which the autonomous mobile device moves is measured by the distance measuring device, the autonomous mobile device can safely move on the floor surface.

In the above-described autonomous mobile device, it is preferable that the rotation trajectory of the rotation control device is determined so that the intervals between the scanning lines of the light beams scanned on the reference plane in each cycle of the distance measuring device are equal.
According to such a configuration, since the light beams are scanned at equal intervals with respect to the reference plane, the shape of the plane corresponding to the reference plane can be measured with a uniform resolution.

The main features of the embodiments described in detail below are listed first.
(Mode 1) The 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 orthogonal to the scanning axis, a sensor that detects the rotation angle of the rotation device, distance data that is input from the laser range sensor, and rotation angle that is input from the sensor And a rotation control device for controlling the rotational movement around the rotation axis of the rotating device.
(Mode 3) When the rotation control device scans the laser from the laser range sensor toward the reference plane, when scanning the light beam at a position far from the laser range sensor on the reference plane, the laser on the reference plane The rotating device is rotated at a slower angular velocity than when scanning a light beam at a position close to the range sensor.
(Mode 4) The rotation trajectory of the rotation control device is determined so that the rotation angular velocity of the rotation device becomes slower as the distance from the laser range sensor to the position where the laser on the reference plane is scanned becomes longer.
(Embodiment 5) The rotation trajectory of the rotation control device is determined such that the intervals between the scanning lines of the light beams scanned on the reference plane in each period of the distance measuring device are equal.
(Mode 6) The rotation control device controls the rotation device using a plane corresponding to the floor surface on which the autonomous mobile device moves as a reference plane.
(Mode 7) 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. It is constituted by a body control device.

  An autonomous mobile device according to an embodiment of the present invention will be described with reference to the drawings. The autonomous mobile device 10 shown in FIGS. 1 and 2 detects an obstacle by measuring the three-dimensional shape of the space, and travels on the floor surface while avoiding the obstacle. Hereinafter, the traveling direction of the autonomous mobile device 10 is referred to as the X direction, the vertical direction is referred to as the Z direction, and the direction perpendicular to the X direction and the Z direction is referred to as the Y direction. 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. Then, based on the difference between the rotational speeds of the motors 46a to 46d calculated based on the rotation amounts o, p, q, and r input from the encoders 48a to 48d and the calculated target rotational speed, A control command value is input to 46a to 46d. Since each motor 46a-46d drives based on the input control command value, the autonomous mobile device 10 moves toward the destination.
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 to be described later are inserted into the through holes 36a and 36b, respectively. Accordingly, the laser range sensor 20 is rotatably supported between the vertical frames 35b and 35c (specifically, the laser range sensor 20 can be rotated around the rotation axis 32 shown in FIG. 1 (that is, the pitch axis of the autonomous mobile device 10). Supported).
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 according to a control command value output from the control device 52. The motor 37 is connected to an encoder 38 that detects a rotation angle θ of the motor 37 (that is, an angle θ with respect to the floor surface of the laser range sensor 20 (hereinafter also referred to as a vertical angle θ)). 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 is configured to determine the angle φ at which the laser is emitted (angle φ with respect to the Y direction of the laser (hereinafter also referred to as horizontal angle φ) (see FIG. 3)). The laser is scanned while changing between 0 ° and 180 °, and the distance data on the scanning surface scanned with the laser is measured. Further, the laser range sensor 20 irradiates the laser in the direction of the vertical angle θ. By rotating the laser range sensor 20 by the rotating device 30, the vertical angle θ at which the laser is emitted is changed. By changing the vertical angle θ of the laser range sensor 20 by the rotating device 30 simultaneously with the change of the horizontal angle φ at which the laser of the laser range sensor 20 emits the laser, the laser range sensor 20 has the horizontal angle φ = 0 ° to 180 ° and The laser is scanned within an angle range of a predetermined vertical angle θ, and distance data is measured.

  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 measurement unit 24, and the rotation angle ψ of the mirror 25 detected by the encoder 28 a is input to the distance measurement unit 24.

  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 24c 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 cycle of 26.4 msec, the cycle 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 pulses 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 26d stores the time data j in association with the rotation angle ψ stored in step S6.

Next, the sensing 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 24c. 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 rotation angle ψ of the mirror 25 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 to 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 after the execution of step S8 (a period in which the encoder 28a detects the rotation angle ψ 36.7 μsec). It is determined whether or not the time 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 angle 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 from the time difference between the time data j and the time data k (specifically, d = (k−j) / c (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 52b stores a rotation track 70 shown in FIG. 7 and a rotation track 72 shown in FIG. The rotation control unit 52b alternately selects the rotation tracks 70 and 72 at predetermined time intervals, and outputs a control command value to the rotating device 30 based on the selected rotation track. Thereby, the rotating device 30 rotates the laser range sensor 20 on the selected rotation path.

A rotational trajectory 70 shown in FIG. 7 is a rotational trajectory for measuring the spatial shape in the traveling direction of the autonomous mobile device 10 over a wide range. As shown in the figure, in the rotation track 70, the rotation center is determined to be θ = 0 °, the upper maximum angle is θ = W1, and the lower maximum angle is determined to be θ = −W1. Therefore, on the rotating track 70, the laser range sensor 20 is rotated so as to reciprocate in an angle range of θ = W1 to −W1. As a result, the laser is emitted in an angle range of θ = W1 to −W1, and the shape of the space in the angle range is measured. Further, the rotational trajectory 70 has a rotational angular velocity dθ in the other period E so that the rotational angular acceleration dθ / dt ² is constant in the period D before and after the timing at which θ becomes the upper maximum angle W1 and the lower maximum angle −W1. / Dt is determined to be constant.

  A rotating track 72 shown in FIG. 8 is a rotating track for measuring the shape of the floor surface in the traveling direction of the autonomous mobile device 10. The rotation path 72 uses a horizontal floor as a reference plane, sets a target position (given as a function of time) to irradiate a laser on the reference plane, and irradiates the set target position with the laser. It has been decided. Before describing the details of the rotation path 72, the positional relationship between the laser range sensor 20 and the position (target position) where the laser from the laser range sensor 20 is irradiated onto the floor surface (reference plane) will be described.

FIG. 10 is a side view of the three-dimensional measuring device 18 when measuring the road surface shape. As shown in FIG. 10, the laser range sensor 20 rotates in the range of the vertical angle θ <0 about the rotation shaft 32 when measuring the road surface shape. A vector K indicates the emission direction of the laser emitted from the laser origin 23a. A point 74 indicates a position on the floor (reference plane) where the laser is irradiated when the laser is emitted from the laser origin 23a. That is, the point 74 is a target position when the laser range sensor 20 irradiates a laser on the floor surface. A vector J indicates a relative position between the laser origin 23 a and the rotation shaft 32. In other words, the laser origin 23a is in the direction of the angle α (the angle α with respect to the laser range sensor 20) from the rotation axis 32 and at a position where the distance J is present. The rotation shaft 32 is at a height H from the floor surface.
The target position 74 moves in the X direction by changing the vertical angle θ of the laser range sensor 20. The distance X in the X direction from the rotary shaft 32 to the target position 74 is determined by the vertical angle θ. As shown in FIG. 10, the height H _23a of the laser origin 23a from the floor surface is H-Jsin (θ + α). Further, X-direction distance _{X 23a} from the laser origin 23a to a target position 74, has a X-Jcos (θ + α) . Therefore, the distance X in the X direction from the rotation shaft 32 to the target position 74 and the vertical angle θ have the following relationship.

Next, the rotation track 72 will be described. The rotational trajectory 72 is determined so that the target position 74 moves in the X direction along the trajectory shown in FIG. That is, the trajectory of the target position 74 is determined so as to reciprocate from the position where the distance X = X1 to the position where the distance X = X2 (<X1). Accordingly, the rotation path 72 is determined so as to reciprocate between an angle −W2 corresponding to the distance X1 and an angle −W3 corresponding to the distance X2. The angle −W2 is calculated based on the relational expression [Expression 1] and X1, and the angle −W3 is calculated based on the relational expression [Expression 1] and X2.
Further, as shown in FIG. 8, the rotating track 72 is constituted by a rotating track in the period F and a rotating track in the period G.

As shown in FIG. 9, the rotation trajectory 72 in the period G is determined such that the target position 74 moves in the X direction at a constant speed dX / dt. That is, the trajectory of the target position 74 in the period G is a linear function f (t) at time t. The rotation trajectory 72 in the period G is determined based on the linear function f (t) and the above-described relational expression [Formula 1]. As a result, as shown in FIG. 8, the rotational trajectory 72 in the period G increases as the distance X from the laser range sensor 20 to the position where the laser on the floor is scanned (ie, the target position 74) increases ( That is, as the distance X approaches X1, the rotational angular velocity is determined to be slower.
As described above, the rotation path 72 is determined so that the target position 74 moves in the X direction at a constant speed in the period G. Further, as described above, the laser range sensor 20 scans the laser at a constant cycle (in this embodiment, 13.2 msec, which is half the rotation cycle of the mirror 25). Therefore, in the period G, the laser is scanned on the floor surface at equal intervals as shown in FIG. Therefore, the rotation control unit 52b controls the rotating device 30 according to the rotation track 72, so that the shape of the floor surface can be measured with uniform resolution. FIG. 12 shows a state where the laser range sensor 20 emits a laser in the direction of the XII-XII line of FIG. As shown in FIG. 12, as the distance to the laser irradiation position becomes longer, the rotational angular velocity is decreased (that is, the angle pitch in FIG. 12 is decreased), whereby the laser irradiation position (laser scanning line) interval ΔX. Are equal. As described above, when the rotation orbit 72 is used, the laser is scanned on the floor surface at equal intervals in the period G, so that the distance data of the floor surface is acquired by the laser range sensor 20 with a uniform resolution. In FIG. 12, since the position of the laser origin 23a and the position of the rotation shaft 32 are very close, they are shown as the same point.

  As shown in FIG. 9, the rotation trajectory 72 in the period F is determined so that the target position 74 changes the speed at a constant acceleration and changes the moving direction. That is, the trajectory of the target position 74 in the period G is a quadratic function g (t) of time t. The rotation trajectory 72 in the period F is calculated based on the quadratic function g (t) and the above [Equation 1].

  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. 10 and 13 to 15. As shown in FIG. 14, the autonomous mobile device 10 is activated in a state where it is placed on a horizontal plane. A position A in FIG. 14 is a position when the autonomous mobile device 10 is activated.
As shown in FIG. 13, 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. 14) as the origin (specifically, sets the midpoint 34 (reference point 34) on the rotating shaft 32 of the autonomous mobile device 10 as the origin). To do). Further, the calculation unit 52a sets an xyz coordinate system in which the X direction of the autonomous mobile device 10 at the time of activation is the x axis, the Y direction is the y axis, and the Z direction is the z 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. 14) as the origin, 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 J between the reference point 34 and the laser origin 23a shown in FIGS. 10 and 15 and the vector K indicating the laser oscillation trajectory. The parameters (x ′ _J , y ′ _J , z ′ _J ) of the offset vector J are constants x ′ _J1 and z ′ _J1 (see FIG. 10) 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 J and the vector K.
Further, the parameters (x ′ _K , y ′ _K , z ′ _K ) of the vector K 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 coordinate (x, y, z) is an angle formed by the coordinate (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.

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.

  In step S <b> 63, the control device 52 of the three-dimensional measurement device 18 selects the rotation trajectory of the rotation device 30. After the activation of the autonomous mobile device 10, the control device 52 selects the rotation path 72.

  When the control device 52 selects the rotation trajectory, the three-dimensional measuring device 18 starts measuring three-dimensional distance data. Thereby, 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). As described above, when the rotation device 30 is controlled in accordance with the rotation path 72, the laser scanning interval ΔX is uniform if the floor surface is flat and horizontal. Therefore, when the coordinates of the measured laser irradiation positions are not equally spaced in the X direction, the autonomous mobile device 10 is said to have obstacles and irregularities without measuring the detailed shape of the positions. I can recognize that.

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 autonomous mobile 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 autonomous mobile 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. In the second and subsequent steps S64, the control device 52 alternately selects the rotation trajectory 70 and the rotation trajectory 72, and outputs a three-dimensional map measured based on the selected rotation trajectory 70 or 72 to the control device 14. Therefore, the three-dimensional measuring device 18 measures the three-dimensional shape data by the rotating track 70 (that is, measures a wide range of spatial shapes) and measures the three-dimensional shape data by the rotating track 72 (that is, measures the floor shape). And repeatedly.
When the autonomous mobile device 10 determines that it has arrived at the destination (YES in step S74), the autonomous mobile device 10 stops moving.

  As described above, the autonomous mobile device 10 alternately and repeatedly performs the measurement of the three-dimensional shape data by the rotating track 70 and the measurement of the three-dimensional shape data by the rotating track 72. The rotational trajectory 72 is determined so that the rotational angular velocity becomes slower as the distance from the laser range sensor 20 to the position where the laser on the floor is scanned becomes longer, thereby the target position 74 where the laser is irradiated. Moves in the X direction at a constant speed. Therefore, when the autonomous mobile device 10 drives the rotation device 30 according to the rotation path 72, the laser is scanned on the floor surface at equal intervals, so that the floor surface shape can be measured with uniform resolution. That is, the shape of the position far from the autonomous mobile device 10 on the floor surface can be measured without reducing the resolution. Therefore, even when there is a small obstacle at a position away from the autonomous mobile device 10 on the floor, the autonomous mobile device 10 can detect the obstacle at an early stage and select a route that avoids the obstacle. it can. In addition, since the floor shape is measured with a uniform resolution, a three-dimensional map with a uniform resolution can be created.

  In the autonomous mobile device of this example, the rotating device was controlled according to the rotation trajectory with the horizontal floor as the reference plane, but the present invention is not limited to such an embodiment, and other planes are used as the reference plane. The rotating device may be controlled by the rotated trajectory. For example, when the autonomous mobile device moves near the wall surface, the rotating device can be controlled according to the rotation trajectory with the wall surface as a reference plane, or when the autonomous mobile device travels on the inclined floor surface, Various planes can be used as the reference plane, such as controlling the rotating device according to the rotation trajectory with the plane as the reference plane.

  Further, in the above-described autonomous mobile device, the rotating device is controlled with a predetermined rotating trajectory, but the measurement range can be changed by generating a rotating trajectory in which the upper maximum angle and the lower maximum angle of the rotating trajectory are changed, The resolution of the measurement (laser scanning interval ΔX) may be changed by generating a rotation trajectory with a changed rotation period. In addition, when a shape that seems to be a plane is detected by space shape measurement, a new rotation trajectory with the plane as a reference plane may be generated. For example, when the shape of the floor surface measured by the rotating track 70 can be approximated to a substantially flat surface, the control device 52 may generate a rotating track whose reference plane is the approximated plane.

  In addition, although the above-described autonomous mobile device is a wheel traveling type autonomous mobile device, it may be a multi-legged walking type robot or the like. By measuring the shape of the floor on which the robot walks, the robot leg can be stepped on to a flatter position on the floor. As a result, stable walking of the robot can be ensured, and the robot can be prevented from falling over.

  Moreover, it is good also as a structure which starts a laser range sensor without rotating normally, and rotates a laser range sensor only when an obstacle is detected by the laser range sensor. As a result, when the obstacle is not detected, the floor shape in the traveling direction is measured in a short cycle, and only when the obstacle is detected, the laser range sensor is rotated by the rotating device to measure the shape of the obstacle. be able to.

  Moreover, in the above-mentioned Example, although the position and moving direction of the autonomous mobile apparatus were calculated from the rotation amount of the wheel which an encoder detects, this invention is not limited to such embodiment. For example, the position and moving direction of the autonomous mobile device may be detected using GPS (Global Positioning System).

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 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 rotation track | orbit 70 of the laser range sensor 20. FIG. The graph which shows the rotation track | orbit 72 of the laser range sensor 20. FIG. The graph which shows the position of the target position 74 of the laser range sensor 20 when rotating the laser range sensor 20 according to the rotation track | orbit 72. FIG. Explanatory drawing at the time of laser emission of the laser range sensor 20. FIG. Explanatory drawing of a laser scanning line when the laser range sensor 20 is rotated according to the rotation track | orbit 72. FIG. Explanatory drawing of the irradiation position of a laser when rotating the laser range sensor 20 according to the rotation track | orbit 72. FIG. The flowchart which shows the process of the calculating part 52a. The perspective view which shows the motion of the autonomous mobile apparatus 10. 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 24d: casing 25: mirror 26: arithmetic unit 26a: control unit 26b: sensing unit 26c: counting unit 26d: storage unit 26e: arithmetic unit 27: resin member 28: motor 28a: encoder 30: rotating device 32: rotating shaft 34 : Reference point 35: Frame 37: Motor 38: Encoder 40: Four wheel bogie 42: Bogie main body 44 a to 44 d: Wheels 46 a to 46 d: Motor 48 a to 48 d: Encoder 52: Controller 52 a: Calculation unit 52 b: Rotation control unit 52 c : Storage unit 70: Rotating track 72: Rotating track 74: Target position

Claims (4)

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 line scanned by a light beam by scanning the light beam around a scanning axis at a predetermined period;
A rotation device to which a distance measurement device is attached, and which rotates the distance measurement device around a rotation axis orthogonal to the scanning axis and the traveling direction of the autonomous mobile device;
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 rotation control device for controlling the rotational movement around the rotation axis of the rotation device;
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 arithmetic device,
When scanning the light beam from the distance measuring device toward the reference plane, the rotation control device is close to the distance measuring device on the reference plane when scanning the light beam at a position far from the distance measuring device on the reference plane. An autonomous mobile device characterized in that a rotating device is rotated at a slower angular velocity than when scanning a light beam at a position.   The rotation trajectory of the rotation control device is determined such that the rotation angular velocity of the rotation device decreases as the distance from the distance measurement device to the position where the light beam on the reference plane is scanned increases. The autonomous mobile device according to claim 1.   The autonomous mobile device according to claim 1, wherein the rotational control device controls the rotational device using a plane corresponding to a floor surface on which the autonomous mobile device moves as a reference plane.   The rotation trajectory of the rotation control device is determined so that the intervals between the scanning lines of the light beams scanned on the reference plane in each period of the distance measuring device are equal intervals. The autonomous mobile device according to any one of the above.

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