JP2006039760A - Mobile robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a mobile robot that moves and/or turns on a plane of travel by attaching a plurality of wheel units to its robot body unit to detect human bodies by means of its simple structure. <P>SOLUTION: The mobile robot 1 which moves and/or turns on the plane 2 of travel by attaching the plurality of wheel units 51-53 to the robot body unit 20 includes a first sensor (piezoelectric infrared sensor) 27 for detecting whether or not there is a human body around the entire circumference of the robot body unit 20, a second sensor (thermopile) 28 for specifying the direction of a human body upon detection, and a third sensor (distance sensor) 22 for measuring the distance to the human body, all of the sensors being mounted in a robot casing 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention can detect a human body in a mobile robot that moves and / or turns on a traveling surface by attaching a plurality of wheel units to the robot body unit, and can change an activity state depending on whether or not the human body is approached. The present invention relates to a mobile robot configured as described above.

  Currently, most robots are used as industrial robots, but in the future, there are expectations for mobile robots for home use that can coexist with humans in the home with high safety.

  As this type of mobile robot, the applicant has previously proposed a mobile robot having a three-wheel configuration. The mobile robot having the three-wheel configuration has a very simple structure, a small number of parts, and a special computer. It is not necessary, the memory is inexpensive, and it can easily maintain posture even on an inclined floor, without hitting an obstacle or falling by a disturbance to injure a person or damaging surrounding equipment. It is difficult to move without changing the course even if there are obstacles, holes or dents, etc., and even if it is used for a long time, the outer surface does not get dirty or scratched, so it is optimal for home use (for example, , See Patent Document 1).

  In addition, autonomous mobile robots for guidance have been developed on behalf of humans at facilities visited by many visitors such as hospitals, museums, and offices. It is configured so that it can be guided by an image sensing means such as a camera (see, for example, Patent Document 2).

Furthermore, in the autonomous mobile device, a distance sensor that detects the front in the traveling direction and an infrared sensor (pyroelectric sensor) that can detect infrared rays emitted from a person can cover the front of the robot from the directional characteristics of the sensors. At least three each of them are attached, and when an obstacle is detected by a distance sensor, when the obstacle is determined to be a person by an infrared sensor, an avoidance operation is performed on the person (for example, a patent) Reference 3).
JP 2004-42246 A JP 2003-280739 A Japanese Patent Application Laid-Open No. 9-185412.

  By the way, since the mobile robot having the three-wheel configuration proposed by the applicant of the present application has a function of detecting a human body, the human body is detected when increasing the relationship between the human and the mobile robot and increasing the number of functions. If the technical idea of the autonomous mobile robot for guidance according to Patent Document 2 described above is introduced as it is when a function is to be added, problems as described in the following items (a) to (c) occur.

  That is, (a). In the above-described autonomous mobile robot for guidance, the configuration of the imaging means is complicated and the identification control algorithm is also complicated and the response performance in order to perform the identification processing by performing the arithmetic processing on the image taken by the imaging means such as a camera. There is a problem that is bad.

  (B). In the above-described autonomous mobile robot for guidance, a computer that performs high-speed processing is required to perform arithmetic processing on images captured by an imaging means such as a camera, which makes the robot expensive and unsuitable for home use. There is a problem.

  (C). In the above-described autonomous mobile robot for guidance, since a human face is photographed by an imaging means such as a camera, there is a problem that privacy such as a personal portrait right is infringed, and the person himself is captured by the photograph itself. On the other hand, there is a problem that disgust occurs.

  Furthermore, in the above-described autonomous mobile device according to Patent Document 3, in order to perform an avoidance operation on a person when a person is detected, it is convenient when applied to a moving body dangerous to the person, It is not suitable for home mobile robots that want to increase the relationship between people and mobile robots, and the total number of distance sensors and infrared sensors is at least six, which increases the cost.

  Therefore, in improving a home mobile robot that can coexist with humans in a small and lightweight home, a function to detect a human body with a simple structure has been added to increase the relationship between humans and mobile robots and increase their functionality. Mobile robots that can do this are desired.

The present invention has been made in view of the above problems, and the invention according to claim 1 is a mobile robot in which a plurality of wheel units are attached to a robot body unit to move and / or turn on a traveling surface.
A first sensor for detecting the presence or absence of a human body over the entire circumference of the robot body unit; a second sensor for specifying the direction of the human body when the human body is detected; and a first sensor for measuring a distance to the human body. 3 is a mobile robot characterized in that the sensor 3 is attached to a robot casing.

The invention according to claim 2 is the mobile robot according to claim 1,
When the human body is detected by the first sensor, the direction of the human body is specified by the second sensor while turning the mobile robot as necessary, and thereafter, distance information from the third sensor It is a mobile robot characterized by autonomously controlling the movement operation according to the above.

  According to the mobile robot of the present invention, in particular, the first sensor (pyroelectric infrared sensor) that detects the presence or absence of a human body over the entire periphery of the robot body unit and the direction of the human body when the human body is detected are specified. Since the second sensor (thermopile) and the third sensor (distance sensor) for measuring the distance to the human body are attached to the robot housing, the relationship between the person and the mobile robot is increased and the multifunctional function is achieved. Can do. Thereby, the problems with respect to Patent Documents 1 to 3 described in the background art can be solved, and it is not necessary to perform processing for identifying a person by performing arithmetic processing on an image photographed by an imaging means such as a camera. Therefore, the identification control algorithm is unnecessary, so the response is good, and a computer that performs high-speed processing is unnecessary, so the mobile robot is inexpensive and ideal for home use. Since the image is not photographed, privacy such as personal portrait rights is not infringed, and the number of sensors for detecting a human body is small and the human body detection structure is simple, so that it can be provided at a lower cost.

  Hereinafter, an embodiment of a mobile robot according to the present invention will be described in detail with reference to FIGS.

FIG. 1 is a plan view showing a mobile robot according to the present invention in plan and various sensors attached to the robot body unit in plan.
FIG. 2 is a block diagram showing a control system in a mobile robot according to the present invention.
FIG. 3 is a plan view for explaining the operation mode of the wheel unit in the mobile robot according to the present invention.
FIG. 4 is a plan view for explaining the rotation and movement of the wheel unit in the mobile robot according to the present invention.

  First, a schematic configuration of a mobile robot according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the mobile robot 1 according to the present invention includes four units. One unit is the robot body unit 20, and the other three are wheel units 51 to 53, and these three wheel units 51 to 53 have the same configuration.

  The mobile robot 1 is provided on the traveling surface 2 while avoiding obstacles on the traveling surface 2 when moving and / or turning on the traveling surface 2 by the three wheel units 51 to 53. By detecting a step and avoiding the step when the amount of the step is greater than a preset value, the human body can be detected and the activity status can be changed depending on whether or not the human body is approached These will be described in detail later.

  The robot body unit 20 described above is provided with three wheel units 51 to 53 below the center of a spherical robot casing 21 formed in a substantially spherical shape, and the three wheel units 51 to 53 are spherical. Since it is attached so as to protrude toward the running surface 2 from three wheel unit openings (not shown) penetrating from the inside of the robot casing 21 along the lower outer peripheral surface 21a, Specifically, the structure is as shown in FIGS.

  Here, after the direction in which the mobile robot 1 normally moves is set to the front side of the robot body unit 20, one wheel unit 51 is attached to the rear side opposite to the front side of the robot body unit 20. The other wheel units 52 and 53 are attached to the left and right of the front side of the robot body unit 20 substantially symmetrically. Accordingly, the three wheel units 51 to 53 are configured such that projections on the traveling surface 2 form substantially 120 ° at substantially equal angles to each other.

  The three wheel units 51 to 53 include cylindrical body parts 51a to 53a, and substantially spherical grounding parts 51b to 53b that are connected to the lower part of the body parts 51a to 53a and contact the running surface 2. The rotating shafts 51c to 53c are attached to the center of the body portions 51a to 53a and rotate integrally with the body portions 51a to 53a and the grounding portions 51b to 53b. The grounding portions 51b to 53b are on the traveling surface 2. The robot body unit 20 is supported by being separated from the traveling surface 2 by being in contact with. Further, the virtual extension lines of the rotating shafts 51 c to 53 c of the wheel units 51 to 53 are configured to intersect at the inner central portion of the spherical robot casing 21.

  At this time, if the grounding portions 51b to 53b of the wheel units 51 to 53 and the traveling surface 2 are respectively rigid bodies, they are point contacts. However, for example, the traveling surface 2 is in surface contact with a soft material such as a carpet. The traveling surface 2 in this embodiment is a rigid flat surface determined by three points where the grounding portions 51b to 53b are grounded.

  The wheel units 51 to 53 are rotated by the rotation drive motors 45 to 47 (FIG. 2) via the motor drive controllers 42 to 44 (FIG. 2) mounted therein or the robot body unit 20. Each of them is driven to rotate independently about 53c.

  Various types of sensors 22 to 28 that are essential parts of the present invention are attached to the robot body unit 20.

  The above-described various sensors 22 to 28 will be described in detail. As shown in FIGS. 7 to 9 to be described later, the upper part on the front side of the spherical robot casing 21 that forms the outer shape of the robot body unit 20. Includes a first ultrasonic sensor 22 having a transmitter 22a and a receiver 22b for transmitting / receiving an ultrasonic beam with a narrow directivity angle to detect an obstacle ahead on the traveling surface 2, and as necessary. And a second ultrasonic unit provided with a transmitter 23a and a receiver 23b that transmit / receive an ultrasonic beam with a wide directivity angle in order to detect a front obstacle that is provided in accordance with the first ultrasonic sensor 22 and cannot be detected by the first ultrasonic sensor 22. A sound wave sensor 23 and a front infrared sensor 24 provided with a light emitting part 24a and a light receiving part 24b for emitting / receiving an infrared beam to detect a front step provided on the traveling surface 2 and a front step amount of the front step. Mounting It is.

  Further, on the upper left part of the spherical robot housing 21, a left step provided on the traveling surface 2 and a light emitting unit 25a for emitting / receiving an infrared beam for detecting the left step amount of the left step and a light receiving unit. A left-side infrared sensor 25 having a portion 25b is attached. On the other hand, a right step provided on the traveling surface 2 and a right step amount of the right step are detected at the upper right portion of the spherical robot casing 21. A right-side infrared sensor 26 having a light emitting part 26a for emitting / receiving an infrared beam and a light receiving part 26b is attached.

  In addition, a pyroelectric infrared sensor 27 for detecting the presence or absence of a human body and the movement of the human body over the entire circumference (omnidirectional) of the robot body unit 20 is provided at a substantially central portion of the top surface of the spherical robot casing 21. It is attached upward.

  Further, in the vicinity of the pyroelectric infrared sensor 27, when the presence of the human body is detected by the pyroelectric infrared sensor 27, the body temperature is detected by detecting the body temperature of the human body while turning the mobile robot 1 as necessary. A thermopile 28 for specifying the position) is attached toward the front of the spherical robot casing 21.

  At this time, the various sensors 22 to 28 are attached from the inside of the spherical robot housing 21 to the outside of the spherical robot housing 21, and the various sensors 22 to 28 are mounted on the spherical robot housing 21. It faces each sensor opening (not shown) penetrating along the outer peripheral surface 21a of 21.

  Next, the configuration of the control system of the mobile robot 1 will be described with reference to FIG. As shown in FIG. 2, inside the robot body unit 20, the mobile robot 1 is comprehensively controlled and a pyroelectric infrared sensor 27 and a thermopile 28 are connected, and external information is detected and measured. An external sensor 32 that outputs information to the outside, a battery 34 that serves as a power source for the mobile robot 1, a battery sensor 35 that detects the remaining amount of the battery 34, and a first super narrow directivity angle The first ultrasonic sensor driving circuit 36 for driving the acoustic wave sensor 22 and transmitting the detection signal to the system controller 31 and the second ultrasonic sensor 23 having a wide directivity angle are driven to obtain the detection signal. The second ultrasonic sensor driving circuit 37 for transmitting to the system controller 31 and the front infrared sensor 24 are driven and detected. Forward infrared sensor drive circuit 38 for transmitting the signal to the system controller 31, left infrared sensor drive circuit 39 for driving the left infrared sensor 25 and transmitting its detection signal to the system controller 31, and right infrared The right-side infrared sensor drive circuit 40 for driving the sensor 26 and transmitting the detection signal to the system controller 31 and the motion control controller 41 for controlling motion of the mobile robot 1 such as movement and / or turning. ing.

  The motion controller 41 described above receives the action content determined by the system controller 31 as a command signal, and the content is based on a control program stored in advance in a memory (not shown) in the motion controller 41. Analyzing and determining how to control each of the three wheel units 51 to 53, and sending the determined contents to the motor drive controllers 42 to 44 provided in the wheel units 51 to 53 as command signals. .

  The three wheel units 51 to 53 are provided with the motor drive controllers 42 to 44 and the rotation drive motors 45 to 47 described above. The rotation drive motors 45 to 47 have the wheel units 51 to 53 mounted thereon. It is an actuator that moves (forward, reverse, side) and / or turns the mobile robot 1 by rotating it appropriately as described later.

  With the above system configuration, the system controller 31 determines the next action to be performed based on the detection information from the various sensors 22 to 28, and the command is transmitted to the motion control controller 41 and the motor drive controllers 42 to 44. ing.

  When an obstacle or a step is detected by the first and second ultrasonic sensors 22 and 23 and the infrared sensors 24 to 26, or when a human body is detected by the pyroelectric infrared sensor 27 and the thermopile 28, 3 By appropriately controlling the rotation of the two wheel units 51 to 53, the mobile robot 1 moves forward, reverse, laterally (moves in the left-right direction with respect to the forward direction), stops, and turns (spins on the spot). The basic operation of the three wheel units 51 to 53 will be described with reference to FIGS.

  In this embodiment, the rotation direction and the rotation speed of the wheel units 51 to 53 are variously changed independently by the motor drive controllers 42 to 44 and the rotation drive motors 45 to 47, so that the grounding portions 51b to 53b and the running surface are changed. Various motions can be imparted to the mobile robot 1 by the frictional force with 2.

  At this time, the mobile robot 1 can be roughly divided and moved in the following five operation modes according to the control of the rotation drive motors 45 to 47, that is, the rotation control method of the wheel units 51 to 53 (see FIGS. 3 and 4). .

  The three wheel units 51 to 53 shown in FIGS. 3 and 4 are attached to the rear side of the robot body unit 20 in correspondence with FIG. 1 shown above, and the wheel units 52 and 53 are attached. Is shown in a plan view in a state of being attached to the left and right of the front side of the robot body unit 20.

  (1) Turn in a stationary state (autorotation), (2) Straight movement (forward, reverse and side), (3) Curve movement, (4) Meandering movement, (5) Linear movement and curve movement while rotating .

  The operation modes (1) to (5) will be described in order.

  (1) Turning (spinning) in a stationary state {see FIG. 3 (1) and FIG. 4 (a)} This is the most basic operation mode, and the three wheel units 51 to 53 are respectively in the same rotational direction. By driving to rotate at the number of rotations, the mobile robot 1 rotates while stationary on the spot. For example, as shown in FIG. 4A, when the rotating shafts 51c to 53c of the wheel units 51 to 53 are rotated in the clockwise direction when viewed from the outside, the mobile robot 1 remains stationary at that position and is viewed from above. Rotates counterclockwise. On the other hand, if the rotation direction of the wheel units 51 to 53 is rotated counterclockwise as opposed to the above, the mobile robot 1 rotates in the clockwise direction while remaining stationary at that position. And the rotation speed of the mobile robot 1 can be increased / decreased by increasing / decreasing the rotation speed per unit time (henceforth a rotation speed) of the wheel units 51-53.

  (2) Straight movement {See FIGS. 3 (2) and 4 (b) to 4 (e)} Of the three wheel units 51 to 53, for example, any one wheel unit 52 is stopped without rotating. The remaining two wheel units 51 and 53 are rotated and driven in opposite directions, so that the mobile robot 1 is straight in the direction along the projection line of the rotating shaft 52c of the wheel unit 52 onto the traveling surface 2. Forward or backward.

  Further, by setting the rotation direction and the number of rotations of the three wheel units 51 to 53, for example, it can be linearly moved in a direction orthogonal to the rotation shaft 52c of the wheel unit 52.

  In this case, the case of proceeding in the opposite direction of the stopped wheel unit 52 is called forward, the case of proceeding to the stopped wheel unit 52 side is called backward, the case of proceeding in the direction perpendicular to the forward or reverse direction is called sideward. This will be described below.

(For forward)
As shown in FIG. 4 (b), when the wheel unit 52 is stopped and the wheel unit 51 is driven in the clockwise direction and the wheel unit 53 is driven in the counterclockwise direction at the same rotation speed, the mobile robot 1 becomes the wheel unit. In the direction along the projection line of the rotating shaft 52c of the rotating shaft 52c onto the traveling surface 2, the vehicle moves straight in the opposite direction of the wheel unit 52 (the direction of the arrow C in the figure).

  Therefore, when the direction in which the mobile robot 1 normally moves is set to the front side of the robot body unit 20 (FIG. 1), the wheel unit 51 is stopped, and the wheel unit 53 is rotated in the clockwise direction. 52 may be driven in the counterclockwise direction at the same rotational speed.

(For backwards)
As shown in FIG. 4C, when both the rotation directions of the wheel units 51 and 53 are reversely rotated with respect to the above-described forward movement, the vehicle moves backward. That is, when the wheel unit 52 is stopped and the wheel unit 51 is driven in the counterclockwise direction and the wheel unit 53 is driven in the clockwise direction at the same rotation speed, the mobile robot 1 travels on the rotating shaft 52c of the wheel unit 52. In a direction along the projection line onto the surface 2, it moves straight in the direction of the wheel unit 52 (the direction of arrow D in the figure).

(In case of side advance)
As shown in FIG. 4 (d), the wheel units 51 and 53 are rotated at the same constant rotation speed in the same rotation direction, the wheel unit 52 is rotated in the direction opposite to the rotation direction of the wheel units 51 and 53, and the wheels. The mobile robot 1 moves in a direction orthogonal to the forward and reverse directions described above by rotating the unit 51, 53 at twice the number of rotations. More specifically, when the rotation direction of the wheel units 51 and 53 is rotated clockwise at a constant rotation speed N and the wheel unit 52 is rotated counterclockwise at the rotation speed 2N, the mobile robot 1 moves forward. It moves linearly in the left direction (direction of arrow E in the figure) orthogonal to the direction.

  On the other hand, as shown in FIG. 4 (e), on the contrary to FIG. 4 (d), the rotation direction of the wheel units 51, 53 is rotated counterclockwise at a constant rotation speed N, and the wheel unit 52 is turned clockwise. When rotating in the turning direction at a rotation speed of 2N, the mobile robot 1 linearly moves in the right direction (in the direction of arrow F in the figure) orthogonal to the forward direction.

  In any of the cases (forward), (reverse), and (side), the moving speed of the mobile robot 1 can be increased or decreased by increasing or decreasing the rotation speed.

  (3) Curve movement {FIG. 3 (3)} The mobile robot 1 can be moved in an arc shape, which is referred to as curve movement. There are two drive control methods for giving this curve movement, which will be described below.

(First curve moving method)
The first curve moving method is a method of rotationally driving the wheel unit 52 that has stopped rotating in the above-described straight movement state. Thereby, the mobile robot 1 moves in an arc shape. At this time, the radius of the moving arc can be changed by changing the rotation speed of the wheel unit 52. That is, the faster the rotation speed of the wheel unit 52, the smaller the radius of the moving arc.

(Second curve moving method)
The second curve moving method is a method in which the other two wheel units 51 and 53 are rotationally driven at different constant rotational speeds while the wheel unit 52 is stopped in the above-described straight traveling state. Thereby, the mobile robot 1 moves in an arc shape. That is, the curve is moved in a circular arc shape having a center on the side of the wheel unit having the smaller number of rotations. In this case, it is possible to vary the radius of the arc by changing the difference in rotational speed between the two wheel units being driven. The larger the difference, the smaller the radius of the moving arc.

  In either case (first curve moving method) or (second curve moving method), the moving speed of the mobile robot 1 is increased or decreased by increasing or decreasing the rotation speed of the wheel units 51 and 53 other than the wheel unit 52. Can be increased or decreased. In particular, in the case of the (first curve moving method), the radius of the moving arc can be changed, and the radius of the moving arc increases as the number of rotations of the wheel units 51 and 53 is increased.

  (4) Serpentine movement {FIG. 3 (4)} In the above-described curve movement, the direction of bending is changed in order to perform meandering movement while swinging left and right. That is, in the first curve moving method described above, the rotation direction of the wheel unit 52 is repeatedly switched between forward rotation and reverse rotation. In the second curve moving method, the wheel units 51 and 53 other than the wheel unit 52 are switched. The zigzag movement is performed by alternately switching different rotation speeds.

  (5) Linear movement and curve movement while rotating {Fig. 3 (5)} The rotation directions of the three wheel units 51 to 53 are cycled like "forward rotation → reverse rotation → forward rotation → ...". When the wheel units 51 to 53 are driven with the rotation speed periodically changed with a time change corresponding to a sine wave and with a certain time difference in the cycle, the mobile robot 1 rotates. While moving straight or curved.

  Next, various sensors 22 to 28 and their operations, which are essential parts of the present invention, will be described with reference to new FIGS.

FIG. 5 is a plan view schematically showing the detection area characteristics of the first and second ultrasonic sensors in the mobile robot according to the present invention,
FIG. 6 is a plan view schematically illustrating the detection area characteristics of the front infrared sensor, the left infrared sensor, and the right infrared sensor in the mobile robot according to the present invention;
FIG. 7 is a right side view showing a state in which a front step is detected using a front infrared sensor in the mobile robot according to the present invention;
FIG. 8 is a right side view for explaining the operation of detecting the front step amount of the front step using the front infrared sensor in the mobile robot according to the present invention.
FIG. 9 is a front view showing a state in which a left step and a right step are detected using a left infrared sensor and a right infrared sensor in a mobile robot according to the present invention,
FIG. 10 is a side view schematically showing the detection area characteristics of the pyroelectric infrared sensor and the thermopile in the mobile robot according to the present invention,
FIGS. 11A and 11B are a plan view, a side view, and a side view showing a state in which the presence or absence of a human body is detected by a pyroelectric infrared sensor in the mobile robot according to the present invention
12 (a) and 12 (b) show a state in which the direction of the human body is detected by the thermopile while turning the mobile robot as necessary after detecting the human body by the pyroelectric infrared sensor in the mobile robot according to the present invention. Plan view, side view,
FIGS. 13A and 13B are a plan view, a side view, and a side view showing a state in which the direction of the human body is specified by the pyroelectric infrared sensor in the mobile robot according to the present invention.
FIG. 14 is a side view showing a state in which the mobile robot approaches the human body according to the distance information from the first ultrasonic sensor in the mobile robot according to the present invention.

  First, as shown in FIG. 5, the direction in which the mobile robot 1 normally moves is set to the front side of the robot body unit 20, and the first provided on the front side of the spherical robot casing 21 of the robot body unit 20. The ultrasonic sensor 22 of 1 is mounted in a direction substantially parallel to the traveling surface 2, that is, in a horizontal direction, and an ultrasonic beam 22 c spreading in a substantially conical shape with a narrow directivity angle of approximately 60 ° is applied to the traveling surface. 2, the ultrasonic beam 22 c is reflected by the obstacle 3 such as the wall surface 3 A in front of the ultrasonic beam 22 c, and the obstacle 3 is detected.

  At this time, the distance of the front detection area 5 for detecting the front of the mobile robot 1 by the ultrasonic beam 22c from the first ultrasonic sensor 22 is several meters. In this embodiment, the center of the narrow directivity angle of about 60 ° is used. Therefore, an ultrasonic sensor having a distance performance of about 3 m from the front of the robot body unit 20 is used. Further, the first ultrasonic sensor 22 functions as a distance sensor that measures the distance from the position where the direction of the human body is specified by the thermopile 28 as will be described later.

  Further, when a width dimension that allows the three wheel units 51 to 53 attached to the mobile robot 1 to pass with a slight margin is called a vehicle width, if the vehicle width is assumed to be, for example, 300 mm, the ultrasonic sensor 22 detects the width. The region in which the vehicle width 300 mm of the mobile robot 1 can be detected from the directivity angle characteristic corresponds to a distance of about 260 mm (= 150 / tan 30 °) from the front of the robot body unit 20 in the front detection area 5 described above. An area where the vehicle width of 300 mm of the mobile robot 1 can be detected is referred to as an avoidance detection area 6 when the mobile robot 1 avoids the obstacle 3, and a forward distance of 260 mm set in the avoidance detection area 6 is set in the system. It is stored in a storage unit (not shown) in the controller 31 (FIG. 2).

  In addition, the regions located on the left and right outside the front detection area 5 are the undetected areas 7L and 7R of the first ultrasonic sensor 22, and approach the mobile robot 1 within the undetected areas 7L and 7R. When there is an obstacle 3 such as a cylinder 3B, the cylinder 3B cannot be detected by the first ultrasonic sensor 22.

  In order to avoid this, a second ultrasonic sensor 23 having a wider directivity angle than the first ultrasonic sensor 22 is provided on the front side of the spherical robot casing 21 of the robot body unit 20 as necessary. .

  The above-described second ultrasonic sensor 23 is also mounted on the front side of the spherical robot casing 21 in a direction that is substantially parallel to the traveling surface 2, that is, in a horizontal direction, and has a wide directivity angle of approximately 120 °. An ultrasonic beam 23c spreading in a substantially conical shape is emitted substantially parallel to the traveling surface 2, and the ultrasonic beam 23c reflected by an obstacle 3 such as a cylinder 3B in front of the ultrasonic beam 23c is received. The obstacle 3 is detected, and the characteristics other than the directivity angle are substantially the same as those of the first ultrasonic sensor 22, and the front is detected by the ultrasonic beam 23 c from the second ultrasonic sensor 23. The distance of the detection area 11 has a performance of about 3 m. In addition, the regions located on the left and right sides outside the front detection area 11 by the second ultrasonic sensor 23 are the undetected areas 12L and 12R of the second ultrasonic sensor 23.

  At this time, when the first and second ultrasonic sensors 22 and 23 are provided, first, the second ultrasonic sensor 23 having a wide directivity angle is started first, and the obstacle 3 is detected. After that, the avoidance operation to the obstacle 3 is performed in the avoidance detection area 6 by the first ultrasonic sensor 22 having a narrow directivity angle.

  In the following description, only the first ultrasonic sensor 22 having a narrow directivity angle is provided without providing the second ultrasonic sensor 23 having a wide directivity angle in order to reduce the number of components and simplify the operation flow. The case where the obstacle 3 is detected by using will be described. At this time, a method of controlling while detecting the obstacle 3 ahead using only the first ultrasonic sensor 22 is as follows.

  (1). When the obstacle 3 is present in the undetected areas 7L and 7R at the time of activation, the obstacle 3 cannot be detected. If the obstacle 3 is not detected within 260 mm forward at each position by turning (in the embodiment, 30 °), advancement is possible at the center position.

  (2). During forward movement, if the obstacle 3 is not detected within the avoidance detection area 6 within a forward distance of 260 mm, the forward movement is continued.

  (3). If the obstacle 3 is detected within a forward distance of 260 mm while moving forward and at a position that is turned left and right by a certain angle, the robot stops and takes an avoidance action.

  In this embodiment, when detecting the obstacle 3 in front of the mobile robot 1, only the first and second ultrasonic sensors 22, 23 or the first ultrasonic sensor 22 are used. It is also possible to use a known infrared sensor (not shown) in place of these ultrasonic sensors.

  Next, as shown in FIG. 6, the front infrared sensor 24 provided on the front side of the spherical robot casing 21 of the robot body unit 20, the left infrared sensor 25 provided on the left and right sides of the spherical robot casing 21, and the right side. In the infrared sensor 26, light emitting units 24a to 26a using infrared light emitting diodes and the like and light receiving units 24b to 26b are integrally formed at the same height position. At this time, the infrared beams 24c to 26c emitted from the light emitting units 24a to 26a of the infrared sensors 24 to 26 are always turned on, and the reflected light of the infrared beams 24c to 26c is received by the light receiving units 24b to 26b. The distances between the infrared sensors 24 to 26 and the reflection points of the infrared beams 24c to 26c can be detected by reading out the light receiving units 24b to 26b at predetermined intervals.

  The infrared beams 24c to 26c from the respective infrared sensors 24 to 26 are mounted so as to irradiate obliquely toward the lower traveling surface 2 while spreading in a substantially conical shape with a narrow directivity angle of approximately 10 °. The front step 4F shown in FIGS. 7 and 8 and the front step amount H of the front step 4F are detected by the infrared sensor 24, and the left step 4L and the left step 4L shown in FIG. The left step amount is detected, and the right infrared sensor 26 detects the right step 4R shown in FIG. 9 and the right step amount of the right step 4R.

  The step 4 including the front step 4F, the left step 4L, and the right step 4R has an upper step that protrudes upward from the traveling surface 2 and a lower step that is formed one step lower than the traveling surface 2. The upper step amount of the upper step that protrudes upward from the running surface 2 is normally called “height”, and the lower step amount of the lower step that is formed one step lower than the running surface 2 is “depth”. Although generally called, in this embodiment, in each of the infrared sensors 24 to 26, the upper step, the upper step amount (height) of the upper step, the lower step, and the lower step amount (depth) of the lower step Since it can be detected, the following explanation will be made without distinguishing between the upper step and the lower step except when necessary.

  At this time, the detection capability of the infrared beams 24c to 26c from the infrared sensors 24 to 26 is about 800 mm, but here the infrared beams 24c to 26c are obliquely irradiated toward the lower running surface 2. The detection areas 15 to 17 of the infrared sensors 24 to 26 are regions including points where the centers of the infrared beams 24c to 26c emitted at a narrow directivity angle of about 10 ° reach the traveling surface 2.

  The detection distance L1 from the front infrared sensor 24 to the traveling surface 2 where the center of the infrared beam 24c irradiated obliquely toward the lower traveling surface 2 reaches the traveling surface 2 is set in advance, for example, to 110 mm. 25, both the detection distances L2 and L3 until the center of the infrared beams 25c and 26c irradiated obliquely toward the lower traveling surface 2 from the right-side infrared sensor 26 reaches the traveling surface 2 are preset to 90 mm, for example. Accordingly, the angles formed between the infrared beams 24c to 26c and the traveling surface 2 are set to values of θ1 to θ3, respectively. At this time, since the left and right detection distances L2 and L3 are both 90 mm, θ2 θ3 is set to the same angle.

  Accordingly, when the detection areas 15 to 17 of the infrared sensors 24 to 26 are illustrated in a plan view, the distance from the robot body unit 20 to the tip of the front detection area 15 is L1 × cos θ1, and from the robot body unit 20 The distance to the tip of the left detection area 16 is L2 × cos θ2, and the distance from the robot body unit 20 to the tip of the right detection area 17 is L3 × cos θ3.

  Then, the values of the detection distances L1 to L3 of the infrared sensors 24 to 26 and the values of the angles θ1 to θ3 formed by the infrared beams 24c to 26c from the infrared sensors 24 to 26 and the traveling surface 2 are set to the system controller 31. It is stored in a storage unit (not shown) in FIG.

  Accordingly, the detection position L1 of the front infrared sensor 24 shown in FIG. 7 is larger than the detection distances L2 and L3 of the left infrared sensor 25 and right infrared sensor 26 shown in FIG. Is set to That is, the relationship between the step detection distance L1 of the front infrared sensor 24 and the step detection distance L2 of the left infrared sensor 25 is set as L1> L2. Similarly, the relationship between the step detection distance L1 of the front infrared sensor 24 and the step detection distance L3 of the right infrared sensor 26 is set as L1> L3 = L2.

  This is because the forward direction can be moved at a high speed, so it is necessary to provide a time margin until the front step 4F is detected and stopped, and the detection distance L1 of the front step 4F is preferably longer to some extent. It is. Regarding the detection of the left and right steps 4L and 4R, the lateral movement in the left and right direction is not performed at a higher speed than the forward movement, so that there is not much time allowance until the left and right steps 4L and 4R are detected and stopped. The detection distances L2 and L3 are preferably shorter with priority given to extending the range of action so that it is close to the right and left steps.

  Here, as shown in FIG. 8, when the mobile robot 1 moves forward on the traveling surface 2, when the front step 4 </ b> F is provided on the traveling surface 2 in front of the mobile robot 1, The front step 4F is detected using the infrared sensor 24, and the front step amount H of the front step 4F is detected.

  At this time, the mobile robot 1 can overcome the upper level difference 4 to some extent as the movement performance. In this embodiment, the upper step of the step amount (height) within 30 mm moves over the premise that it can overcome the threshold in the home. Therefore, it is necessary to avoid the upper step exceeding 30 mm so as not to collide because the upper step cannot be overcome. Also, if the lower step 4 is a lower step within 30 mm, it can be climbed again even if the lower step is descended. Therefore, the lower step within 30 mm may be entered without avoiding it. There is no need to avoid the lower step exceeding 30 mm. Along with this, a storage unit (not shown) in the system controller 31 (FIG. 2) stores an allowable allowable step amount value 30 mm in advance.

  When the mobile robot 1 is moving forward on the traveling surface 2, the detection distance L1 by the infrared beam 24c from the front infrared sensor 24 intersects the traveling surface 2 at an obliquely lower position of 110 mm as described above. The detection distance L1 = 110 mm is stored in advance in a storage unit (not shown) in the system controller 31 (FIG. 2), and the angle formed between the infrared beam 24c and the traveling surface 2 is θ1. Since it is stored in advance in a storage unit (not shown) in the system controller 31 (FIG. 2), the system controller 31 (FIG. 2) is a height between the front infrared sensor 24 and the traveling surface 2. It is known that H1 is H1 = L1 × sin θ1.

  On the other hand, when the mobile robot 1 moves forward and the front infrared sensor 24 detects the front step 4F provided on the traveling surface 2, the infrared beam 24c from the front infrared sensor 24 is reflected by the upper surface of the front step 4F. Therefore, by reflecting the detection voltage value of the reflected light into a distance value using a voltage / distance conversion table (not shown) in the front infrared sensor drive circuit 38 (FIG. 2), reflection on the upper surface of the front step 4F is performed. The hourly detection distance L1 ′ is obtained with a value shorter than the above-described detection distance L1. Thereafter, the detection distance L1 ′ during reflection obtained by the front infrared sensor drive circuit 38 (FIG. 2) is input to the system controller 31 (FIG. 2), so that the system controller 31 and the front infrared sensor 24 It is detected that the height H1 ′ between the upper surface of the step 4F is H1 ′ = L1 ′ × sin θ1, and the front step amount (height) H of the front step 4F is H1−H1 ′ = (H1− L1 ′) × sin θ1 is detected.

  Then, the system controller 31 (FIG. 2) allows the internal determination unit (not shown) to previously store the front step amount (height) H of the front step 4F in the internal storage unit (not shown). It is determined whether or not the step amount value is larger than 30 mm. When the front step amount (height) H of the front step 4F is larger than the allowable step amount value 30 mm, the command of the system controller 31 (FIG. 2) Based on the above, an operation for avoiding the front step 4F is performed.

  When detecting the left step amount of the left step 4L with the left infrared sensor 25 or when detecting the right step amount of the right step 4R with the right infrared sensor 26, the front step sensor 4F is used with the front infrared sensor 24 described above. Since the previous step amount H may be detected by the same method as described above, detailed description thereof is omitted.

  Next, as shown in FIG. 10, the pyroelectric infrared sensor 27 attached upward to a substantially central portion of the top surface of the spherical robot casing 21 of the robot body unit 20 in the mobile robot 1 has a predetermined detection. The human body M can be detected only within the range, and the presence or absence of the human body M is detected by the movement of the human body M having the body temperature within the range, but the direction (position) of the human body M is specified. I can't do it.

  The pyroelectric infrared sensor 27 described above uses a ferroelectric material such as lead zirconate titanate (PZT), lead titanate (PT), or barium titanate / strontium (BST) having a pyroelectric effect. The differential output type is configured to detect the presence of the human body M by absorbing the far infrared rays generated from the human body M.

  The detection area 18 by the pyroelectric infrared sensor 27 described above extends upward in a substantially conical shape from a substantially central portion of the top surface of the spherical robot casing 21 and is within a certain detection distance. The apex angle of the cone which is the detection area 18 by the pyroelectric infrared sensor 27 is, for example, 92 °, and the detection distance is, for example, 2000 mm upward from the substantially central portion of the top surface of the spherical robot casing 21. The diameter of the tip portion of the detection distance is, for example, 5000 mm.

  The pyroelectric infrared sensor 27 is mounted so that the detection area 18 faces the upper part of the mobile robot 1 to detect the presence or absence of the human body M over the entire circumference (all directions) of the mobile robot 1. Can do. That is, even if the human body M approaches the mobile robot 1 from any direction, it is possible to reliably detect.

  Here, when the height of attachment of the pyroelectric infrared sensor 27 to the mobile robot 1 is 180 mm from the traveling surface 2, for example, the distance Kmm from the mobile robot 1 to the human body M when detecting the approaching human body M is the human body. If the height of M is Tmm, K = (T−180) / tan 44 °. For example, when an adult with a height of 160 cm approaches the mobile robot 1 within 147 cm, the mobile robot 1 detects the adult, When the child approaches the mobile robot 1 within 105 cm, the mobile robot 1 detects the child. Since the mobile robot 1 does not detect the human body M without a certain height in this way, for example, it is possible to prevent unnecessary movement when a short infant or a small animal such as a dog or cat approaches. Can do.

  Next, after setting the direction in which the mobile robot 1 normally moves to the front side of the robot body unit 20, the thermopile 28 attached toward the front of the spherical robot housing 21 in the vicinity of the pyroelectric infrared sensor 27. In addition, there is a detection area 19 that extends in a substantially conical shape, and the apex angle of the cone that is the detection range is, for example, 40 °. At this time, the detection distance of the detection area 19 by the thermopile 28 is set to be longer than the radius 2500 mm of the tip portion of the detection area 18 by the pyroelectric infrared sensor 27 toward the front side of the mobile robot 1. .

  The above-described thermopile (thermopile) 28 has a plurality of thermocouples connected in series, such as a junction of p-type polysilicon and n-type polysilicon or a junction of polysilicon and aluminum, and radiates from the human body M in a non-contact manner. When the received infrared rays are received, an electromotive force corresponding to the amount of energy is generated, and the body temperature generated by the human body M is measured to be an integral output type. And the direction (position) where the human body M exists can be specified by comparing the body temperature of the human body M detected by the thermopile 28 and the ambient temperature.

  From the above, the basic idea for detecting the human body M in the mobile robot 1 is that the pyroelectric infrared sensor 27 detects the presence or absence of the human body M, and then the thermopile while turning the mobile robot 1 as necessary. At 28, the direction (position) of the human body M is specified. Thereafter, the mobile robot 1 is moved in the direction of the human body M, and stops when the distance information of the first ultrasonic sensor 22 (FIG. 1) reaches a certain value, that is, when it approaches the human body M.

  Here, a specific method for detecting the human body M and the operation of the mobile robot 1 will be described in detail. First, as shown in FIGS. 11A and 11B, the human body M is within the detection area 18 of the pyroelectric infrared sensor 27 attached to the approximate center of the top surface of the spherical robot housing 21 in the mobile robot 1. When a part of is entered, the pyroelectric infrared sensor 27 detects the human body M. However, the pyroelectric infrared sensor 27 cannot identify the direction (position) in which the human body M is present.

  Next, as shown in FIGS. 12A and 12B, when the mobile robot 1 detects the presence of a human body by the pyroelectric infrared sensor 27, the mobile robot 1 attaches a thermopile 28 attached in the vicinity of the pyroelectric infrared sensor 27. If the human body M is immediately detected in the detection area 19 of the thermopile 28 while being operated, the direction (position) of the human body M is specified here, and the mobile robot 1 is moved to the first position as will be described later with reference to FIG. Depending on the distance information of the ultrasonic sensor 22, the moving operation such as approaching to the human body M or stopping on the spot is autonomously controlled.

  On the other hand, when detecting the presence of a human body by the pyroelectric infrared sensor 27 and operating the thermopile 28, if the human body M is not detected in the detection area 19 of the thermopile 28, the mobile robot 1 first displays the figure on the spot. The turning (spinning) operation as described in 3 (1) is performed. At this time, in the embodiment, the mobile robot 1 is turned leftward, but may be turned rightward. Further, the pyroelectric infrared sensor 27 may be in an activated state or may be deactivated.

  If the direction (position) of the human body M is detected by the thermopile 28 as shown in FIGS. 13A and 13B while turning the mobile robot 1, the mobile robot 1 stops the turning operation.

  At this time, as shown in FIG. 14, since the human body M is present in front of the mobile robot 1, the direction (position) of the human body M can be specified. Thereafter, the mobile robot 1 performs the first ultrasonic wave. The human body M in the ultrasonic sensor detection area (= equivalent to the front detection area described in FIG. 5) 5 of the first ultrasonic sensor 22 from the position where the sensor 22 is activated and the direction (position) of the human body M is specified. Until the distance output from the first ultrasonic sensor 22 reaches a predetermined value. That is, the mobile robot 1 comes close to the human body M and stops.

  When the mobile robot 1 performs such an action, the mobile robot 1 recognizes itself and moves close to it when viewed from the human side. Therefore, it is as if a pet is approaching a human. looks like. Such behavior makes the mobile robot 1 friendly to humans and can exist as a partner that coexists with humans. Therefore, it is possible to increase the relationship between the human and the mobile robot 1 and achieve multi-functionality.

  Thereby, the problems with respect to Patent Documents 1 to 3 described in the background art can be solved, and it is not necessary to perform processing for identifying a person by performing arithmetic processing on an image photographed by an imaging means such as a camera. Therefore, since the identification control algorithm is unnecessary, the responsiveness is good, and a computer that performs high-speed processing is unnecessary. Therefore, the mobile robot 1 is inexpensive and suitable for home use. The privacy of the individual's portrait right and the like is not infringed, and the number of sensors for detecting the human body is small and the human body detection structure is simple.

  Next, among various sensors 22 to 28 which are the main part of the present invention, an operation flow for detecting an obstacle by the first ultrasonic sensor 22, and a human body is detected by the pyroelectric infrared sensor 27 and the thermopile 28. The operation flow to be described will be described in combination with the new FIGS. 15 to 18 and FIG. 2 described above.

In addition, since the description about the operation | movement flow which detects a level | step difference by the infrared sensors 24-26 is not entangled with the human body detection operation | movement, description here is abbreviate | omitted.

FIG. 15 is a flowchart showing a process for detecting and avoiding an obstacle ahead using the first ultrasonic sensor in the mobile robot according to the present invention;
FIG. 16 is a diagram for explaining a case where a moving speed according to the distance from an obstacle is set in the mobile robot according to the present invention;
FIG. 17 shows a forward process for controlling the moving speed according to the distance from an obstacle when the obstacle is ahead using the first ultrasonic sensor to avoid the obstacle in the mobile robot according to the present invention. Flowchart shown,
FIG. 18 is a flowchart showing a process in which a mobile robot detects a human body and acts in the mobile robot according to the present invention.

  (1) Flow for Detecting an Obstacle and Performing Avoidance Action FIG. 15 shows a follow chart for detecting an obstacle 3 ahead using the first ultrasonic sensor 22 and taking an avoidance action. The basic obstacle avoidance method is a process in which the mobile robot 1 repeats a left turn in 30 ° steps. Here, two counters of rotation_counter (hereinafter referred to as R counter) and obstacle_counter (hereinafter referred to as OB counter) are prepared. In this embodiment, the mobile robot 1 is turned left, but there is no problem if it is turned right.

  First, in step S101, the R counter is reset to zero. The R counter is used to prevent an infinite loop that repeats a left turn in a situation surrounded by obstacles all around, and turns 12 times in 360 ° turns, that is, 30 ° step turns. Is repeated, emergency processing (step S111) is performed in a deadlock state. This determination process is performed in step S102.

  In step S103, the OB counter is reset to zero. The OB counter is a counter that counts continuously detecting three positions in front without an obstacle. As described above, the condition for enabling the advance at the time of start-up is that the obstacle is not detected within a forward distance of 260 mm at each position by turning by a certain left and right angle (30 ° in the embodiment) with reference to the initial position. In order to simplify processing in actual control, this left / right turning control is replaced with turning control in one direction (in the embodiment, left turning), and an obstacle is detected within a distance of 260 mm forward three times in succession. Otherwise, it is considered that the obstacle is avoided at the position returned to the center direction (in the embodiment, the right turn at the end).

  Next, in step S104, the R counter is incremented by 1, and in step S105, distance information from the first ultrasonic sensor 22 to the front obstacle is input. Next, in step S106, it is determined whether or not the distance information input from the first ultrasonic sensor 22 is within 260 mm. If there is an obstacle within 260 mm, the process returns to step S102. On the other hand, if there is no obstacle within 260 mm in step S106, a left turn of 30 ° is performed in step S107, and the OB counter is incremented by 1 in step S108. In step S109, it is determined whether the OB counter is 2. If not, the process returns to 104. On the other hand, if the OB counter is 2 in step S109, it means that no obstacle has been detected within a forward distance of 260 mm three times in succession, so that in the next step S110 a right turn 30 ° is required to return to the center position. Then, the process is terminated, and then the forward action process described below is executed.

  (2) Flow of moving forward while detecting an obstacle FIG. 17 shows a flowchart of moving forward while detecting an obstacle ahead using the first ultrasonic sensor 22. At this time, as shown in FIG. 16, the forward speed is set in a three-stage mode according to the distance from the obstacle. That is, when the distance to the obstacle exceeds 1500 mm, the speed is the high speed mode, and when the distance to the obstacle is over 500 mm and within 1500 mm, the speed is the medium speed mode, and the distance to the obstacle exceeds 260 mm and within 500 mm. If the speed is in the low speed mode, and of course within 260 mm, it will naturally stop.

  As shown in FIG. 17, first, in step 121, distance information with respect to the front obstacle from the first ultrasonic sensor 22 is input, and in step S122, it is determined whether or not the distance to the obstacle is within 260 mm. If the distance from the obstacle is within 260 mm, stop processing is performed in step S123 and this flow is terminated. On the other hand, if there is no obstacle within 260 mm in step S122, the process proceeds to step S124 to determine whether the distance from the obstacle is within 500 mm. If the distance from the obstacle is within 500 mm in step S124, the process proceeds to step S125, the forward speed is set to the low speed mode, and the process returns to step S121. On the other hand, if the distance to the obstacle exceeds 500 mm in step S124, the process proceeds to step S126 to determine whether or not the distance to the obstacle is within 1500 mm. If it is determined in step S126 that the distance from the obstacle is within 1500 mm, the process proceeds to step S127, the forward speed is set to the medium speed mode, and the process returns to step S121. On the other hand, if it exceeds 1500 mm in step S126, the forward speed is set to the high speed mode in step S128, and the process returns to step S121.

  The above loop is repeated, and when the distance from the obstacle is within 260 mm, the mobile robot 1 stops moving forward and stops, and the process is terminated, and the process proceeds to the above-described process for avoiding the obstacle.

(3) Flow in which the mobile robot acts by detecting a human body FIG. 18 shows a flowchart in which the mobile robot 1 acts by detecting a human body. First, initialization of a computer (not shown) provided in the mobile robot 1 is performed by variable initialization, timer initialization, port input / output designation, input / output designation, and interrupt prohibition processing from step S201 to step S205. .

  Next, in step S206, all the rotational drive motors 45 to 47 are stopped.

  Next, in step S207, detection information from the pyroelectric infrared sensor 27 is input. In step S208, it is determined whether or not the human body is detected by the pyroelectric infrared sensor 27, and no human body is detected. Return to step S207, and if a human body is detected, proceed to step S209. That is, the mobile robot 1 is in a standby state until the human body is detected by the pyroelectric infrared sensor 27. This state is called a standby mode.

  Next, when it is determined in step S208 that the human body has been detected by the pyroelectric infrared sensor 27, a power-on process is executed in step S209. Specifically, the power-on process is performed by causing an LED (not shown), which is a light-emitting means, to emit light, driving the thermopile 28 and the external sensor 32, and communicating with the motion controller 41 to prepare for system driving. .

  Next, in step S210, after the presence of a human body is detected by the pyroelectric infrared sensor 27, the mobile robot 1 is turned leftward as necessary, and a timer (not shown) is started in step S211. In this state, the mobile robot 1 is rotating leftward at that position. In this embodiment, the mobile robot 1 is turned left, but there is no problem even if it is turned right.

  Next, in step S212, detection information from the thermopile 28 is input. In step S213, it is determined whether or not the timer value has reached a first predetermined value (for example, 5 seconds). For example, when 5 seconds have elapsed, the process returns to step S205 to enter a standby mode. On the other hand, if the timer does not reach the first predetermined value (for example, 5 seconds) in step S213, the temperature information (detection information) input from the thermopile 28 in step S214 is 35 ° C to 39 ° C. Whether or not the temperature is within the range is determined. If the temperature is not within the temperature range (35 ° C to 39 ° C), the process returns to step S212 to be within the temperature range (35 ° C to 39 ° C). In this case, the 5-second timer is stopped in step S215 and the value of this timer is reset to 0, and the left turn of the mobile robot 1 is stopped in step S216, and then, in FIG. The process proceeds to the described forward process.

  At this time, when the above-described timer reaches the first predetermined value (for example, 5 seconds), the reason for performing the process of returning to the standby mode is that there is a wall such as a low screen between the human body and the mobile robot 1. Even if the human body is detected by the pyroelectric infrared sensor 27, the above-described wall is obstructed and the human body cannot be detected by the thermopile 28, and the human body direction (position) cannot be specified. This is to prevent the mobile robot 1 from entering an infinite loop that repeats turning forever, in order to cope with a case where the mobile robot 1 has moved away from the mobile robot 1 immediately after approaching it. The reason why the temperature information detected by the thermopile 28 in step S214 is within the range of 35 ° C. to 39 ° C. is to detect the body temperature of the human body.

  Therefore, in the process up to step S216, the mobile robot 1 has detected the human body and specified its direction. In step S217, the forward process is performed. In this forward process, the human body is regarded as a kind of obstacle, and when it reaches a certain distance, for example, within 260 mm as described above with reference to FIG. To do. The mobile robot 1 performs the actions described above with reference to FIGS. 11 to 14 through the series of flow processes described above.

  The contents of the processing that follows are the flow in which the mobile robot 1 receives a command from a person and shifts to a specific operation mode, the mobile robot 1 does not receive a command from a person for a certain period, and does not detect a human body. In this case, the process of returning to the standby mode in the event of a failure is described.

  First, in step S218, a timer for measuring a certain time is operated. Subsequently, in step S219, detection information from the pyroelectric infrared sensor 27 is input, and in step S220, presence / absence determination processing is performed.

  If the human body is not detected by the pyroelectric infrared sensor 27 in step S220, the process proceeds to step S221 to determine whether or not the timer has reached a second predetermined value (for example, 5 minutes). When the predetermined value of 2 (for example, 5 minutes) is reached, the process returns to step S205 to enter the standby mode. On the other hand, if the timer has not reached the second predetermined value (for example, 5 minutes), the process proceeds to step S223.

  If the human body is detected by the pyroelectric infrared sensor 27 in step S220, the value of the 5-minute timer is reset to 0 in step S222, and the process proceeds to step S223. If the human body is not detected by the above process for a predetermined period (for example, 5 minutes) set in advance by a 5-minute timer, it is determined that there is no person and the mobile robot 1 returns to the standby mode.

  Next, in step S223, the mobile robot 1 inputs a command from a person in the next operation mode. The command input method includes a switch provided in the main body of the mobile robot 1, an infrared remote controller, and voice input by human voice. Subsequently, the input content of the command is determined in step S224, and if there is no input or the command is other than a predetermined input, the process returns to step S218. If a predetermined command is input, the process proceeds to step S225 to stop each timer described above, reset the value of each timer to 0, and execute a predetermined operation mode. In this embodiment, either a remote operation mode in which a person operates the mobile robot 1 with a remote controller (not shown) in step S226 or an autonomous mode in which the mobile robot 1 autonomously operates in step S227. Do something.

  With the above process, the mobile robot 1 automatically shifts to the standby mode when there is no operation mode command from a person and the detection of the human body is not performed for a predetermined time. This process prevents the mobile robot 1 from inadvertently consuming the battery.

It is the top view which showed the various sensors attached to the robot main body unit planarly while showing the mobile robot which concerns on this invention planarly. 1 is a configuration diagram showing a control system in a mobile robot according to the present invention. In the mobile robot which concerns on this invention, it is a top view for demonstrating the operation mode of a wheel unit. In the mobile robot which concerns on this invention, it is a top view for demonstrating rotation and movement of a wheel unit. FIG. 5 is a plan view schematically showing the detection area characteristics of the first and second ultrasonic sensors in the mobile robot according to the present invention. FIG. 5 is a plan view schematically showing the detection area characteristics of the front infrared sensor, the left infrared sensor, and the right infrared sensor in the mobile robot according to the present invention. In the mobile robot which concerns on this invention, it is the right view which showed the state which detects a front level | step difference using a front infrared sensor. FIG. 6 is a right side view for explaining an operation of detecting a front step amount of a front step using a front infrared sensor in the mobile robot according to the present invention. In the mobile robot which concerns on this invention, it is the front view which showed the state which detects a left level | step difference and a right level | step difference using a left side infrared sensor and a right side infrared sensor. FIG. 4 is a side view schematically showing a detection area characteristic of a pyroelectric infrared sensor and a thermopile in the mobile robot according to the present invention. (A), (b) is the top view and side view which showed the state which detects the presence or absence of a human body with a pyroelectric infrared sensor in the mobile robot which concerns on this invention. (A), (b) shows a state in which the direction of the human body is detected by the thermopile while turning the mobile robot as necessary after detecting the human body by the pyroelectric infrared sensor in the mobile robot according to the present invention. It is a top view and a side view. (A), (b) is the top view and side view which showed the state which specifies the direction of a human body with a pyroelectric infrared sensor in the mobile robot which concerns on this invention. In the mobile robot which concerns on this invention, it is the side view which showed the state in which a mobile robot approaches a human body according to the distance information from a 1st ultrasonic sensor. 6 is a flowchart showing processing for detecting and avoiding an obstacle ahead using the first ultrasonic sensor in the mobile robot according to the present invention. It is a figure for demonstrating the case where the moving speed according to the distance with an obstruction is set in the mobile robot which concerns on this invention. In the mobile robot according to the present invention, when detecting and avoiding an obstacle ahead using the first ultrasonic sensor, a flowchart showing a forward process for controlling the moving speed according to the distance from the obstacle. It is. 5 is a flowchart showing processing in which the mobile robot detects a human body and acts in the mobile robot according to the present invention.

Explanation of symbols

1 ... Mobile robot,
2 ... running surface,
3 ... Obstacle, 3A ... Wall surface, 3B ... Cylinder,
4 ... step, 4F ... front step, 4L ... left step, 4R ... right step,
6 ... avoidance detection area by the first ultrasonic sensor,
15 ... front detection area by front infrared sensor,
16: Left detection area by left infrared sensor,
17: Right detection area by right infrared sensor,
18 ... detection area by pyroelectric infrared sensor,
19 ... Detection area by thermopile,
20 ... Robot body unit,
21 ... Spherical robot housing,
22 ... First ultrasonic sensor, 22a ... Transmitter, 22b ... Receiver, 22c ... Ultrasonic beam,
23 ... Second ultrasonic sensor, 23a ... Transmitter, 23b ... Receiver, 23c ... Ultrasonic beam,
24 ... front infrared sensor,
24a ... light emitting part, 24b ... light receiving part, 24c ... infrared beam,
25. Left infrared sensor,
25a ... Light emitting part, 25b ... Light receiving part, 25c ... Infrared beam,
26 ... right side infrared sensor,
26a ... light emitting part, 26b ... light receiving part, 26c ... infrared beam,
27 ... Pyroelectric infrared sensor 27,
28 ... Thermopile,
31 ... System control controller,
32 ... External sensor, 33 ... Output device, 34 ... Battery, 35 ... Battery sensor,
36 ... 1st ultrasonic sensor drive circuit, 37 ... 2nd ultrasonic sensor drive circuit,
38 ... Front infrared sensor drive circuit, 39 ... Left infrared sensor drive circuit,
40 ... right infrared sensor drive circuit, 41 ... motion control controller,
42-44 ... motor drive controller,
45-47 ... rotational drive motor,
51-53 ... wheel unit,
51a-53a ... trunk part, 51b-53b ... grounding part, 51c-53c ... rotating shaft,
M ... Human body.

Claims (2)

In a mobile robot that moves and / or turns on a traveling surface by attaching a plurality of wheel units to the robot body unit,
A first sensor for detecting the presence or absence of a human body over the entire circumference of the robot body unit; a second sensor for specifying the direction of the human body when the human body is detected; and a first sensor for measuring a distance to the human body. A mobile robot characterized in that the sensor 3 is attached to a robot housing. The mobile robot according to claim 1,
When the human body is detected by the first sensor, the direction of the human body is specified by the second sensor while turning the mobile robot as necessary, and thereafter, distance information from the third sensor A mobile robot characterized by autonomously controlling the movement operation according to the situation.

Images