JP2019053367A - Image processing device and movement support device - Google Patents

Abstract

To determine presence or absence of an obstacle in a front space of a mobile body, by a simple constitution.SOLUTION: A movement support device 1 comprises an image processing device 10 which has an imaging unit 3 for capturing a stereo image of a front space, and an arithmetic device 5. The arithmetic device comprises: a position selection unit which selects a plurality of measuring points P0-P5 from the surface captured as the stereo image; a plane equation calculation unit which calculates a plurality of plane equations, on the basis of the three-dimensional space coordinates of the plurality of measuring points; and a determination unit which determines presence or absence of an obstacle in a front space, on the basis of the plurality of plane equations.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an image processing apparatus and a movement support apparatus.

  There is known an image processing apparatus that estimates the state of a front space based on a captured stereo image.

  There is a need for an image processing apparatus that is worn when a visually handicapped person or the like walks and can easily determine whether there are obstacles such as steps, stairs, walls, and objects in front of him / herself.

  For example, Patent Document 1 discloses an image processing device for performing plane detection when a robot or an automobile moves autonomously. This image processing apparatus calculates a horizontal plane and a vertical plane in the front field of view of the distance sensor.

  Patent Document 2 discloses a step edge estimation device for causing a robot that can move autonomously to move up and down stairs. The present invention estimates the position and direction of the stepped portion on the assumption that there is a step in front.

  Patent Document 3 discloses a road surface level difference detection device that detects a road level level difference from a plurality of image data captured by a stereo camera.

  However, in the case of a pedestrian, there are many obstacles to be noted other than the horizontal and vertical planes, such as steps, stairs, and objects at the feet. None of the patent documents disclose an image processing apparatus that easily discriminates an obstacle in front of a pedestrian.

  Therefore, there is a need for an image processing apparatus that can easily determine whether there are obstacles such as steps, stairs, walls, and objects in the front space.

Japanese Patent Laid-Open No. 10-063210 Japanese Patent Laying-Open No. 2015-043317

  It is an object of the present invention to provide an image processing apparatus that determines the presence or absence of an obstacle in a front space of a moving body with a simple configuration.

  An image processing apparatus according to the present invention includes an imaging unit that captures a stereo image of a front space, a position selection unit that selects a plurality of measurement points from the surface captured by the stereo image, and a three-dimensional space of the plurality of measurement points. A plane equation calculation unit that calculates a plurality of plane equations based on the coordinates, and a determination unit that determines the presence or absence of an obstacle in the front space based on the plurality of plane equations.

  According to the present invention, the presence or absence of an obstacle in the front space of the moving body is determined with a simple configuration.

BRIEF DESCRIPTION OF THE DRAWINGS (a) Schematic block diagram which shows embodiment of the movement assistance apparatus concerning this invention, (b) The front perspective view which shows a mode that the wearer mounted | worn with the imaging part which the said movement assistance apparatus has. It is a functional block diagram of the said movement assistance apparatus. It is a schematic diagram which shows the measurement point which the position selection part which the image processing apparatus with which the said movement assistance apparatus has has selects in the said wearer's front space. It is a schematic diagram which shows the mode of the plane which passes along the said measurement point drawn by assuming that the optical axis of the said imaging part is horizontal. It is a flowchart of the said movement assistance apparatus. (A) The state of the front space when moving forward in a place with a wall on the front right side, (b) An analysis example by the image processing apparatus. (A) The state of the front space when rotating leftward at a place where there is a wall on the left side of the front, (b) An analysis example by the image processing device. (A) State of front space when there is an obstacle in front of the front, (b) Analysis example by the image processing device. (A) The state of the front space when there is a descending staircase in front of the front, (b) An analysis example by the image processing device. It is a schematic diagram which shows the mode of the normal vector calculated from the measurement point and the said measurement point when there is a downward staircase in front of the front. (A) The state of the front space when there is an ascending stairs in front of the front, (b) An analysis example by the image processing device. It is a schematic diagram which shows the mode of the normal vector calculated from the measurement point and the said measurement point in case there exists an uphill staircase in front. It is a schematic diagram which shows the mode of the normal vector calculated from the measurement point and the said measurement point in case there exists an uphill step in front of the front.

  Embodiments of an image processing apparatus and a movement support apparatus according to the present invention will be described below with reference to the drawings.

Overview of Movement Support Device As shown in FIGS. 1A and 1B, the movement support device 1 includes a fixed unit 2, an imaging unit 3, a transmission unit 4, an arithmetic device 5, a battery 6, Is provided. The imaging unit 3 is fixed to the user by the fixing unit 2 so that an image in the traveling direction of the user can be captured. The imaging unit 3 and the arithmetic device 5 constitute an image processing device 10.

  The fixing unit 2, the imaging unit 3, and the transmission unit 4 are configured in a ring shape corresponding to the outer periphery of the head of the user 100. The imaging unit 3 is a stereo camera configured by a pair of cameras. The imaging unit 3 is fixed near the left and right temples of the user 100. The pair of cameras are connected by a resin member on the front side of the user 100 so that the distance between the pair of cameras does not change. The stereo camera 3 is connected by a fixed portion 2 on the back side of the user 100. The fixing part 2 is a belt having a metal fitting, for example, and the length can be adjusted in accordance with the outer peripheral length of the head of the user 100. Further, the fixing portion 2 may be an elastic belt.

  The imaging unit 3 and the transmission unit 4 are connected to the arithmetic device 5 in a wired or wireless manner. The arithmetic device 5 analyzes the image in the traveling direction of the user 100 based on the stereo image captured by the imaging unit 3 and determines the presence or absence of an obstacle. The arithmetic device 5 outputs the determined result to the transmission unit 4.

  Here, the obstacle is a concept including a wide range of objects and obstacles to be noted when moving, such as steps, stairs, walls, and objects at the feet. The step includes one up step and a down step, and the stair includes an up stair and a down stair. The obstacle includes an uphill slope and a downhill slope. The movement assumes a walk when the visually impaired person wears and uses the movement assistance apparatus 1.

  The transmission unit 4 receives the result calculated by the calculation device 5, and informs the user 100 whether or not there is an obstacle in the traveling direction of the user 100 and what kind of obstacle is present. It is the mechanism part which transmits. The transmission unit 4 is, for example, a bone conduction headphone. In the present embodiment, the transmission unit 4 is fixed so as to come into contact with the head of the user 100 at a connection portion between one camera of the imaging unit 3 and the fixing unit 2. The transmission unit 4 is not limited to the bone conduction headphones, and may be a device such as an earphone or a speaker that transmits information by voice, or may be a device that transmits information by touch. Various devices such as a projection onto the retina of the user 100 with a laser can be applied.

  The battery 6 supplies power to the imaging unit 3, the transmission unit 4, and the arithmetic device 5.

  The arithmetic device 5 and the battery 6 are attached to the waist, chest, etc. of the user 100.

  The fixed position of the imaging unit 3 may not be the head as long as the front space of the user 100 can be imaged. For example, it may be a shoulder or a chest. Depending on the fixing position of the imaging unit 3, various shapes such as a neck pillow type and a chest band type can be applied to the fixing unit 2.

Configuration of Movement Support Device 1 As illustrated in FIG. 2, the movement support device 1 includes an imaging unit 3, an A / D conversion unit 31, a position selection unit 32, a position calculation unit 33, and a plane equation calculation unit 36. Further, the movement support apparatus 1 includes an imaging unit angle calculation unit 40 and a coordinate conversion unit 41 for correcting the inclination of the imaging unit 3. Furthermore, the movement support apparatus 1 includes a flat road determination unit 50, a recording unit 60, and a transmission unit 4.

  In the following description, the traveling direction of the user 100 on the horizontal plane is the x-axis direction, the direction orthogonal to the x-axis on the horizontal plane is the y-axis direction, and the direction orthogonal to the horizontal plane is the z-axis direction. This xyz coordinate system is also called a user coordinate system. Further, the forward direction in the stereo image is defined as the X-axis direction, the left-right direction orthogonal to the X-axis is defined as the Y-axis direction, and the vertical direction orthogonal to the X-axis and Y-axis is defined as the X-axis direction. This XYZ coordinate system is also referred to as an imaging unit coordinate system. The imaging unit coordinate system is obtained by an array of pixels of the imaging unit.

  The imaging unit 3 captures a stereo image of the space in front of the user 100 in the traveling direction. In order to image the road surface at the foot of the user 100, the imaging unit 3 is fixed facing slightly downward from the horizontal.

  The A / D conversion unit 31 digitally converts the stereo image captured by the imaging unit 3.

  As illustrated in FIG. 3, the position selection unit 32 selects a plurality of measurement points from the surface captured in the digitally converted stereo image. The plurality of measurement points are a point P0, a point P1, a point P2 (hereinafter also referred to as “first measurement point group”) on the surface close to the user's 100 feet, and a surface slightly ahead of the user's feet. Point P3, point P4, and point P5 (hereinafter also referred to as “second measurement point group”).

  The first measurement point group and the second measurement point group are points that are not on the same straight line. For example, the point P0 is the front of the user 100, the point P1 is diagonally forward right with respect to the point P0, and the point P2 is diagonally forward left with respect to the point P0. The point P3 is a position that is in front of the user 100 and is slightly farther from the user 100 than the point P0 in the traveling direction. Point P4 is diagonally forward right with respect to point P3, and point P5 is diagonally forward left with respect to point P3. Measurement points P4 and P5 that are farthest from the imaging unit 3 in the second measurement point group are located farther from the imaging unit 3 than any measurement point in the first measurement point group.

  The position calculation unit 33 measures the three-dimensional spatial coordinates of the points P0 to P5 in the imaging unit coordinate system.

● Angle correction of the imaging unit 3 The imaging unit 3 is fixed with its optical axis facing slightly downward from the horizontal. In other words, as shown in FIG. 4, when the horizontal in the stereo image captured by the imaging unit 3 is interpreted as the same as the horizontal in the user coordinate system, the road surface appears to rise obliquely.

  Therefore, the imaging unit angle calculation unit 40 and the coordinate conversion unit 41 calculate the angle of the optical axis of the imaging unit 3 with respect to the horizontal plane in the user coordinate system, and the measurement points P0 to P5 obtained on the imaging unit coordinate system. The three-dimensional space coordinates are converted into three-dimensional space coordinates on the user coordinate system.

  As shown in FIGS. 2 to 4, the imaging unit angle calculation unit 40 obtains a vector V1 connecting the points P0 and P1, and a vector V2 connecting the points P0 and P2. Then, the imaging unit angle calculation unit 40 calculates the outer product of the vector V1 and the vector V2, and derives the normal vector V100 of the plane P100 passing through the points P0 to P2. Since the plane P100 is a plane that is perpendicular to the normal vector V100 and passes through the point P0, the imaging unit angle calculation unit 40 can obtain a plane equation of the plane P100 from the normal vector V100 and the point P0.

The plane equation of the plane P100 having the normal vector V100 of the components (A, B, C) is expressed as follows.
AX + BY + CZ + D = 0 (1)
X, Y, and Z are variables, and A, B, C, and D are constants.

  The normal vector V100 may be derived by the plane equation calculation unit 36 described later, and the imaging unit angle calculation unit 40 may receive information on the normal vector V100 from the plane equation calculation unit 36.

The imaging unit angle calculation unit 40 calculates an inclination angle A100 in the xz-axis space of the normal vector V100 of the plane P100 according to equation (2).
(2)
Is the length of the normal vector V100.

The coordinate conversion unit 41 converts the three-dimensional spatial coordinates of the points P0 to P5 obtained on the imaging unit coordinate system into the user coordinate system using the angle A100 as the angle of the optical axis of the imaging unit 3. When the three-dimensional space coordinates obtained on the imaging unit coordinate system of the point Pn (n is a natural number starting from 0) are (Xn, Yn, Zn), the three-dimensional space coordinates (xn, yn, zn) are obtained by the following equations (3) to (5), respectively. In the present embodiment, n is a natural number from 0 to 5.
xn = Xn × cos (−π / 2 + angle A100) −Zn × sin (−π / 2 + angle A100) (3)
zn = Zn × sin (−π / 2 + angle A100) + Zn × cos (−π / 2 + angle A100) (4)
yn = Yn (5)
The unit of the angle A100 is radians. From the expressions (3) to (5), the three-dimensional space coordinates in the user coordinate system of the points P0 to P5 are obtained.

  The normal vector V100 may be slightly inclined in the yz-axis space on the actual road surface. Since the influence of the inclination of the yz axis space is minute, the inclination of the yz axis space is ignored in the present embodiment. However, the imaging unit angle calculation unit 40 may calculate the inclination of the yz-axis space. The coordinate conversion unit 41 may convert the three-dimensional space coordinates of the measurement points P0 to P5 into the user coordinate system based on the inclination of the yz-axis space.

  As illustrated in FIG. 3, the plane equation calculation unit 36 derives a plane equation representing a plane passing through the first measurement point group and a plane equation representing a plane passing through the second measurement point group. Specifically, the plane equation calculation unit 36 obtains a vector v1 connecting the points P0 and P1 converted into the user coordinate system and a vector v2 connecting the points P0 and P2 converted into the user coordinate system. . Then, the plane equation calculation unit 36 calculates the outer product of the vector v1 and the vector v2, and derives the normal vector V10 of the plane P10 passing through the points P0 to P2.

  Further, the plane equation calculation unit 36 obtains a vector v3 connecting the points P3 and P4 converted into the user coordinate system and a vector v4 connecting the points P3 and P5 converted into the user coordinate system. The plane equation calculation unit 36 calculates the outer product of the vector v3 and the vector v4, and derives a normal vector V11 of the plane P11 passing through the points P3 to P5.

The plane equation of the plane P10 having the normal vector V10 is expressed as follows.
ax + by + cz + d = 0 (6)
x, y, and z are variables, and a, b, c, and d are constants.

● Flat road determination unit 50
As shown in FIG. 2, the flat road determination unit 50 includes a plane height calculation unit 52, a plane angle calculation unit 53, and a determination unit 70.

  The plane height calculation unit 52 calculates the z component of the first measurement point group points P0 to P2, that is, the average of the heights, and calculates the height Z10. Further, the plane height calculation unit 52 calculates the z component of the second measurement point group points P3 to P5, that is, the average of the heights, and calculates the height Z11.

  The plane angle calculation unit 53 calculates the inclinations of the plane P10 and the plane P11 based on the components of the normal vector V10 of the plane P10 and the normal vector V11 of the plane P11. First, the plane angle calculation unit 53 normalizes the normal vectors V10 and V11, and calculates normalized normal vectors V20 and V21.

Assuming that the component of the normalized normal vector V20 is (a20, b20, c20), the tilt angle A10 of the vector V10 with respect to the traveling direction can be obtained by Expression (6).
A10 = π / 2-acos (a20) (6)
The tilt angle B10 of the vector V10 with respect to the left-right direction is obtained by Expression (7).
B10 = π / 2-acos (b20) (7)

  Similarly, the plane angle calculation unit 53 calculates the tilt angle A11 with respect to the traveling direction of the formula vector V11 and the tilt angle B11 with respect to the left-right direction using the formulas (6) and (7).

  The recording unit 60 records the heights Z10 and Z11 calculated in the past, the tilt angles A10 and A11 with respect to the traveling direction of the planes P10 and P11, and the tilt angles B10 and B11 with respect to the left-right direction. The recording unit 60 can record a plurality of values calculated in the past. The recording unit 60 transmits each value to the determination unit 70 in response to a call from the determination unit 70.

  The recording unit 60 may store all the values after the start of measurement, or record a plurality of the latest values and receive the newest data when receiving the new data. Data may be deleted.

  The determination unit 70 determines the presence or absence of an obstacle in the front space of the user 100 based on the heights Z10 and Z11 and the tilt angles A10, A11, B10, and B11 of the planes P10 and P11.

  The determination unit 70 may store a predetermined threshold value for each value, and may determine that there is an obstacle in the front space when each currently calculated value exceeds the threshold value. The determination unit 70 may receive each value calculated in the past from the recording unit 60 and determine the presence or absence of an obstacle based on each value calculated in the past and each value currently calculated. Specifically, it may be determined that there is an obstacle in the front space when each of the most recently calculated values and each of the currently calculated values continuously exceed the threshold.

-Flowchart of the movement assistance apparatus 1 Operation | movement of the movement assistance apparatus 1 demonstrated so far is demonstrated. As illustrated in FIG. 5, first, the movement support apparatus 1 images the front space of the user 100 by the imaging unit 3 to obtain a stereo image (step S1). And the movement assistance apparatus 1 A / D-converts the image imaged by the A / D conversion part 31 (step S2).

  Next, the position selection unit 32 selects a plurality of measurement points from the surface of the A / D converted image (step S3). The plurality of measurement points are a total of 6 points: points P0, P1, and P2 on the surface near the user's 100 feet, and points P3, P4, and P5 on the surface slightly ahead of the user's feet. It is.

  Next, the position calculation unit 33 calculates the three-dimensional spatial coordinates in the imaging unit coordinate system of the plurality of measurement points P0 to P5 (step S4).

  The imaging unit angle calculation unit 40 calculates the inclination of the optical axis of the imaging unit 3 from the three-dimensional space coordinates of the first measurement point group points P0 to P2 (step S5). The recording unit 60 records the calculated inclination of the optical axis of the imaging unit 3 (step S61).

  The imaging unit angle calculation unit 40 reads the optical axis inclination of the imaging unit 3 calculated in the past from the recording unit 60, and based on the optical axis inclination calculated in the past and the currently calculated optical axis inclination. The inclination of the optical axis of the imaging unit 3 may be calculated. If the currently calculated optical axis inclination is too large, a value calculated in the past instead of the currently calculated value may be transmitted to the coordinate conversion unit 41 as the optical axis inclination of the imaging unit 3. Good. Furthermore, the imaging unit angle calculation unit 40 may calculate the current inclination of the optical axis of the imaging unit 3 based on a plurality of values calculated in the past. By using the inclination of the optical axis calculated in the past for calculation, even when the space at the foot of the user 100 is not flat in a narrow space such as a staircase or while climbing up and down stairs, It is possible to appropriately determine the presence or absence of an obstacle in the space.

  The coordinate conversion unit 41 converts the three-dimensional spatial coordinates in the imaging unit coordinate system of the points P0 to P5 into the three-dimensional spatial coordinates in the user coordinate system based on the inclination of the optical axis of the imaging unit 3 (step S6). ).

  The plane equation calculation unit 36 calculates the normal vector V10 of the plane P10 passing through the points P0, P1, and P2 (step S7). Further, the plane equation calculation unit 36 calculates the normal vector V11 of the plane P11 passing through the points P3, P4, and P5 (step S8).

  The plane height calculation unit 52 calculates the height Z10 of the first measurement point group (step S9). Further, the plane height calculation unit 52 calculates the height Z11 of the second measurement point group (step S10). The recording unit records the heights Z10 and Z11 (step S62).

  The plane angle calculation unit 53 calculates a tilt angle A10 in the advancing direction with respect to the horizontal direction and a tilt angle B10 in the left-right direction of the plane P10 (step S11). Further, the plane angle calculation unit 53 calculates a tilt angle A11 in the traveling direction relative to the horizontal direction and a tilt angle B11 in the left-right direction of the plane P11 (step S12). The recording unit records the tilt angles A10, A11, B10, and B11 of the calculated plane P10 and plane P11, respectively (step S63).

  The determination unit 70 calls information on the heights Z10 and Z11 calculated in the past and the tilt angles A10, A11, B10, and B11 from the recording unit 60 (step S13). The determination unit 70 determines whether or not there is an obstacle in the front space of the user 100 based on the previously calculated height and tilt angle and the currently calculated height and tilt angle (step S14). The recording unit 60 records the determination result (step S64).

  The movement support apparatus 1 is assumed to be worn by a user who is walking, for example, and sequentially determines whether there is an obstacle ahead. Therefore, the determination unit 70 can capture how the distance between the user and the obstacle gradually changes as the user walks by using each value calculated in the past for determination. Therefore, the obstacle determination accuracy is improved.

  If the determination unit 70 determines that it is necessary to transmit to the user based on the determination result, the determination unit 70 transmits that fact to the transmission unit 4. The transmission unit 4 transmits the determination result to the user by various methods (step S15). When the determination unit 70 determines that it is not necessary to transmit to the user, the determination unit 70 does not transmit information to the transmission unit 4.

  The transmission unit 4 may notify the user only when there is an obstacle, or may notify the user that he / she can walk safely when there is no obstacle.

  Finally, the movement support apparatus 1 returns to step S1, and periodically repeats the operations of steps S1 to S15 and steps S61 to S63.

  Thus, the movement assistance apparatus 1 can determine the presence or absence of an obstacle around the user 100 with a simple configuration by analyzing the space of the foot and the space slightly ahead of the foot. .

Measurement Example 1: When there is a wall in front of the user in the direction of travel As shown in FIG. 6A, when the wall 200 exists slightly ahead of the user's 100 feet, the point of the second measurement point group P3 and point P5 are on the floor, and point P4 rides on the wall 200. Accordingly, the plane P11 is measured while being inclined from the upper right to the lower left.

  FIG. 6B shows a time-series change of each value when the user 100 approaches the wall obliquely. In this measurement example, a total of 16 values, each of 15 values calculated in the past and currently calculated values, are shown. That is, each value up to frame-15 is plotted with the time point of the currently calculated value as frame 0 and the time point of the value calculated once before as frame-1.

  In each subsequent measurement example, the measurement frequency of the movement support apparatus 1 is 10 Hz. That is, the movement support apparatus 1 performs a measurement once every 100 ms and analyzes the state of the front space. In other words, the time interval between frames is 100 ms. The measurement frequency is arbitrary, and the more frequently the measurement is, the higher the accuracy is, but the processing load on the computing device 5 of the movement support apparatus 1 increases. When a person wears and uses it, if the walking speed of the person is considered to be about 1 m / s, a measurement of about 10 Hz that analyzes changes in the front space every about 0.1 m is suitable. According to such a movement support apparatus 1, it is possible to reduce erroneous detection due to instantaneous fluctuations, and it is possible to more accurately determine the front space of the moving user 100.

  In the figure, the horizontal tilt angle B11 of the plane P11 rises from around frame-10 to around 50 °. Further, the inclination angle A11 in the traveling direction of the plane P11 is lowered to around −40 °. Further, reflecting the fact that the point P1 gets on the wall 200 as the user 100 progresses, the horizontal tilt angle B10 of the plane P10 also gradually increases. From these pieces of information, the determination unit 70 can determine that a plane inclined obliquely to the right with respect to the traveling direction exists ahead. In this case, the determination unit 70 determines that there is a wall on the right front side, and notifies the user through the transmission unit 4.

Measurement Example 2: When there is a wall in front of the user's rotation direction As shown in FIG. 7A, when there is a wall in front of the left side of the user 100, the user 100 rotates in the left direction near the wall. In this case, in the second measurement point group, the point P5 is on the floor surface, and the points P3 and P4 ride on the wall 201. Further, the point P2 of the first measurement point group also gets on the wall 201 as the user 100 rotates.

  As shown in FIG. 7B, the tilt angles of the plane P10 and the plane P11 gradually increase in the minus direction from the vicinity of the frame-9 in both the traveling direction and the left-right direction. Accordingly, the determination unit 70 determines that an obstacle has appeared ahead as the user 100 rotates, and transmits the fact to the user 100 through the transmission unit 4.

Measurement Example 3: When there is an obstacle in front of the direction of travel of the user As shown in FIG. 8A, when the user 100 walks toward the obstacle 202, the point P4 and the point P5 are obstacles almost simultaneously. Get on the object 202.

  As shown in FIG. 8B, the tilt angle B11 in the left-right direction of the plane P11 hardly changes, but the tilt angle A11 in the traveling direction suddenly changes from the frame 11 to the minus direction to −50 °. It goes down to the vicinity. Accordingly, the determination unit 70 determines that there is an obstacle in front of the user 100 in the traveling direction, and transmits the fact to the user 100 through the transmission unit 4.

Measurement Example 4: When there is a descending staircase in front of the user in the direction of travel As shown in FIG. 9A, when the user 100 approaches the descending staircase, the plane P11 is arranged on the descending staircase step. Is done. As shown in FIG. 9B, the tilt angle A11 from the frame -13 to the plane P11 increases in the plus direction. The tilt angle A10 of the plane P10 is substantially constant. Further, the planar height Z11 of the plane P11 changes so as to be positioned below the planar height Z10 of the plane P10. From these things, the determination part 70 determines with the down stairs or the down slope having appeared in front of the user 100's advancing direction. Note that the tilt angle A11 in the traveling direction of the plane P11 is about 20 ° when the plane P11 is approaching the stairs. As shown in FIG. 10, since this value corresponds to the slope of the stairs, it can be seen that the image processing apparatus 10 can analyze the descending stairs.

Measurement Example 5: When there is an ascending stairs in front of the user's direction of travel As shown in FIG. 11A, when the user 100 reaches before the ascending stairs, the plane P11 is placed on the ascending stairs. Is done. As shown in FIG. 11B, the plane P11 tilt angle A11 increases from the vicinity of the frame −10 to the − side. Moreover, the change that the plane height of the plane P11 is located above the plane P10 has begun. From these things, the determination part 70 determines with the uphill step or the uphill slope having appeared in the advancing direction front of the user 100. FIG. Note that the tilt angle A11 in the traveling direction of the plane P11 is approximately −20 ° when the plane P11 is approaching the stairs. As shown in FIG. 12, since this value corresponds to the slope of the staircase, it can be seen that the image processing apparatus 10 can analyze the state of the upstairs.

Measurement Example 6: When there is a step in front of the user's direction of travel As shown in FIG. 13, for example, when there is a step between the floor of the entrance and the soil, the tilt angles A10, A11, B10, B11 are small. However, the heights Z10 and Z11 are different from each other. Therefore, the determination unit 70 compares the planar heights Z10 and Z11 to determine whether or not there is a step ahead. This is the same for the up and down steps.

  Thus, the image processing apparatus 10 can determine the presence or absence of an obstacle in the front space of the moving object with a simple configuration. In addition, the movement support apparatus 1 including the image processing apparatus 10 can transmit the presence / absence of an obstacle in the front space of the moving body to the wearing user 100.

  In the description of the movement support apparatus according to the present invention, it has been described assuming an apparatus that is worn and used by a human. However, the technical idea of the present invention can also be applied to, for example, a mechanism unit that is attached to a robot or incorporated in a robot to determine the presence or absence of an obstacle.

DESCRIPTION OF SYMBOLS 1 Movement assistance apparatus 3 Imaging part 10 Image processing apparatus 32 Position selection part 36 Plane equation calculation part 70 Determination part

Claims (9)

An imaging unit that captures a stereo image of the front space;
A position selection unit for selecting a plurality of measurement points from the stereo image;
A plane equation calculation unit that calculates a plurality of plane equations based on the three-dimensional spatial coordinates of the plurality of measurement points;
A determination unit that determines the presence or absence of an obstacle in the front space based on the plurality of plane equations;
An image processing apparatus comprising:   The determination unit calculates inclinations of planes represented by the plurality of plane equations from the plurality of plane equations, and determines the presence or absence of an obstacle in the front space based on the inclinations of the respective planes. The image processing apparatus described.   The determination unit calculates, from the plurality of plane equations, the inclination of the plane represented by the plurality of plane equations in the front-rear direction and the left-right direction orthogonal to the front-rear direction, respectively, and the plane inclination in the front-rear direction and the left-right direction The image processing apparatus according to claim 1, wherein a type of an obstacle in the front space is determined based on an inclination of a plane in a direction.   A recording unit that records the inclination of the plane calculated in the past is further provided, and the determination unit is configured to obstruct the obstacle in the front space based on the inclination of the plane calculated in the past and the inclination of the plane that is currently calculated. The image processing apparatus according to claim 1, wherein the presence or absence of the image is determined.   Based on the plane equation, an imaging unit angle calculation unit that calculates an angle of the imaging unit with respect to the plane represented by the plane equation as an imaging unit angle, and coordinate conversion that corrects the inclination of the stereo image based on the imaging unit angle The image processing apparatus according to claim 1, further comprising a unit.   The plurality of plane equations includes a first plane equation and a second plane equation, and the plurality of measurement points are different from the first measurement point group including the plurality of measurement points and the second measurement point group. The plane equation calculation unit includes a second measurement point group including points, and the plane equation calculation unit calculates the first plane equation representing a plane passing through the first measurement point group and represents the plane passing through the second measurement point group. The image processing apparatus according to claim 1, wherein the second plane equation is calculated.   The measurement point that is farthest from the imaging unit in the second measurement point group is at a position farther forward from the imaging unit than any measurement point of the first measurement point group. Image processing device.   The determination unit calculates an average height of the first measurement point group and the second measurement point group, respectively, and determines the presence or absence of an obstacle in the front space based on the average height. 8. The image processing apparatus according to 7. An image processing apparatus configured to be fixed to a moving body and having an imaging unit that captures a stereo image of a space in front of the moving body;
A transmission unit for transmitting a processing result of the image processing apparatus to the moving body;
A movement support apparatus comprising:
The said image processing apparatus is a movement assistance apparatus which is an image processing apparatus in any one of Claims 1 thru | or 8.