JP5761152B2 - Traveling device - Google Patents

Description

  The present invention is, for example, a travel support device that supports walking of a pedestrian who is difficult to walk autonomously such as a weak color person, a senior car that supports movement of an elderly person, a power assist cart that power-assisted movement of a distribution car, etc. The present invention relates to a traveling device.

This type of travel support device is roughly classified into a guide robot that guides a pedestrian to a destination and a guide device that can be used as a guide dog.
As a guidance robot, information necessary for the guided person to move to the destination, such as direction instructions when moving to the destination, is displayed on the display, and the guidance guides the guided person to the destination while guiding the guided person. A robot has been proposed (see, for example, Patent Document 1).

As another guide robot, a guide robot that displays information necessary for the guided person to move to the target and outputs the information from the speaker by voice, and guides the guided person to the destination while guiding the guided person. Has been proposed (see, for example, Patent Document 2).
Furthermore, as another guidance robot, the featured part of the guided person is extracted by image processing using an imaging means such as a camera to identify the guided person, and the featured part is referred to the identified guided person. Meanwhile, an autonomous mobile robot for guidance that guides a guided person to a destination while guiding the person being guided has been proposed (see, for example, Patent Document 3).

On the other hand, as a guide device, an obstacle, a thing approaching the user, a thing to be avoided for the user, such as a step, is detected and the course is corrected for the traveling direction, or the traveling direction is A guide device has been proposed in which a user is guided by applying a brake (see, for example, Patent Document 4).
As another guide device, the monitor TV image is collated with the image stored in the memory chip to determine what the image captured by the monitor TV is and inform the user by voice. A guide dog robot has been proposed in which a signal is sent to the brake when the image is an image (for example, see Patent Document 5).

  Furthermore, a robot that makes contact with and guides a blind blind owner like a guide dog, comprising means for recognizing the owner and means for recognizing that the owner is in contact with the robot. There has been proposed a robot having a function of searching for and contacting an owner when separated (for example, Patent Document 6).

JP 2008-152504 A JP 2007-276080 A JP 2003-280739 A JP-A-11-212259 JP 2003-225266 A JP 2006-345960 A

However, in the guidance robots described in Patent Documents 1 to 3, it is possible to guide the person to be guided to the destination by image or voice, but guidance is given to a pedestrian who is blind. There is an unresolved issue that cannot be done.
On the other hand, in the guide devices described in Patent Documents 1 to 3, when the destination is input in advance, the guidance guide is given to the pedestrian who is blind and the obstacle just before However, there is no specific description on how to detect and discriminate obstacles to guide visually impaired people, and form a guide device that changes the guide dog. There is an unresolved issue that is impossible.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and an object thereof is to provide a traveling device that can travel safely by detecting an obstacle.

In order to achieve the above object, a first aspect of the traveling device according to the present invention includes an operation input unit that a pedestrian who performs walking support holds and inputs a moving direction, and also includes a traveling unit. A self-propelled vehicle capable of traveling in the direction of the vehicle, travel control means for controlling the travel of the self-propelled vehicle based on the movement direction input by the operation input unit, and positions of obstacles around the self-propelled vehicle. an obstacle detecting means for detecting, on the basis of the the traveling direction of the self-propelled body by the travel control unit based only on the operation of the input unit inputs the position information of the obstacle detected by the obstacle detecting means itself Obstacle contact determining means for determining whether or not the running body is in contact with the obstacle, and traveling direction correcting means for correcting the traveling direction of the traveling control means based on the determination result of the obstacle contact determining means. The travel direction correcting means is connected to the obstacle. It has a danger map that represents the degree of danger calculated based on the line trajectory and the distance by the relationship between the moving speed and the turning speed, and travels with reference to the danger degree map based on the moving speed and the turning speed that to correct the direction.

Also, a second aspect of the traveling device according to the present invention, which has an operation input unit for pedestrian performing walking assistance inputs the moving direction by grasping, you can travel in any direction with a traveling unit A self-propelled vehicle, travel control means for controlling the travel of the self-propelled vehicle based on the moving direction input by the operation input unit, and obstacle detection for detecting the position of an obstacle around the self-propelled vehicle And the obstacle of the self-propelled vehicle based on the position information of the obstacle detected by the obstacle detection device and the traveling direction of the self-propelled vehicle by the traveling control device based only on the input of the operation input unit. An obstacle contact determination means for determining presence or absence of contact with an object; and a travel direction correction means for correcting a travel direction of the travel control means based on a determination result of the obstacle contact determination means. means, based on the arrival time for the obstacle There have arrival time map configured danger area and safety area, to correct the traveling direction by referring to the arrival time map based on the moving speed and the turning speed of the self-propelled body.

According to a third aspect of the traveling apparatus of the present invention, the traveling control means includes a movement speed detecting means for calculating a movement speed of the self-propelled body in response to an input from the operation input section, and the operation input section. Turning speed detecting means for detecting the turning speed of the self-propelled body in response to an input of the obstacle, the obstacle contact determining means being in contact with the obstacle based on the moving speed and the turning speed of the self-propelled body Determine.

Moreover, the 4th aspect of the traveling apparatus which concerns on this invention has the structure by which the said self-propelled body had the structure by which the support arm extended while inclining back was formed in the front upper surface of a base, and this support arm An operation input unit is formed on the top of the pedestrian so that a pedestrian can grip and input a moving direction.
Moreover, the 5th aspect of the traveling apparatus which concerns on this invention has the width | variety more than the shoulder width of the said pedestrian, and the recessed part which accommodates the leg of the pedestrian who assists walking on the back side is formed, Drive with the pedestrian following the back.

Moreover, the 6th aspect of the traveling apparatus which concerns on this invention is comprised by the said grip part which the said operation input part hold | maintains a pedestrian, and the 6-axis force sensor connected with this grip part.
Further, according to a seventh aspect of the traveling apparatus of the present invention, the obstacle detection unit includes a scanner range sensor that scans in a horizontal direction in front of the self-propelled body, and the scanner range sensor includes at least The position of the obstacle is detected by scanning a predetermined angle range in front of the self-propelled body.

Further, an eighth aspect of the traveling device according to the present invention is such that the self-propelled body has a front wheel having a caster structure and a pair of left and right driving rear wheels that are driven by an electric motor that is driven forward and backward by the traveling control means . It has.
Further, a ninth aspect of the traveling device according to the present invention includes a traveling surface distance detection unit in which the obstacle detection unit measures a distance from a traveling surface preceding the traveling direction of the self-propelled body, and the traveling surface. And a floor surface determination unit that detects a step on the traveling surface as an obstacle based on the measurement data detected by the distance detection unit.

  According to the present invention, the pedestrian or the driver operates the operation input unit because it has the operation input unit for inputting the moving direction and the self-propelled body that has the traveling unit and can travel in any direction. Thus, the self-propelled body is travel-controlled in the direction according to the will of the pedestrian or driver. Then, when an obstacle is detected in the traveling direction of the self-propelled body, the traveling direction of the traveling control means is corrected, so that it can be performed safely and reliably while leading walking in the direction according to the will of the visually impaired, for example. .

It is a perspective view which shows one Embodiment of the walk assistance apparatus which concerns on this invention. It is a front view of FIG. It is a right view of FIG. It is a bottom view of FIG. It is explanatory drawing which shows the detection range of a laser range sensor. It is a block diagram which shows a traveling control apparatus. It is a block diagram which shows an arithmetic processing unit. It is a flowchart which shows an example of the traveling control processing procedure performed with a traveling control part. It is a schematic diagram which shows the positional relationship of a self-propelled body and an obstruction. It is explanatory drawing which shows the positional relationship and risk map of a self-propelled body and an obstruction. It is a figure with which it uses for description of the arrival time map to the obstruction which shows other embodiment of this invention, (a) is a figure which shows the positional relationship of an obstruction and a traveling body, (b) shows an arrival time map. It is a characteristic diagram. It is a flowchart which shows an example of the traveling control processing procedure in other embodiment of this invention. It is a flowchart which shows an example of the correction process procedure of FIG. It is explanatory drawing which shows other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 is a perspective view showing an embodiment of a walking support apparatus according to the present invention, FIG. 2 is a front view, FIG. 3 is a right side view, and FIG. 4 is a bottom view.
In the figure, 1 is a walking assistance device as a traveling device, and this walking assistance device 1 has a self-propelled body 2 that travels in an arbitrary direction. The self-propelled body 2 includes a base 3 that is formed in a streamline shape with a sharp front end when viewed from the bottom and has a height of, for example, a pedestrian's knee that supports walking. The base 3 is formed with a width at the rear end face larger than the shoulder width of the pedestrian, and a recess 4 is formed on the rear end face to accommodate the lower leg of the pedestrian that is recessed forward.

On the bottom surface of the base 3, a caster 5 is pivotably disposed on the front end side, and driving wheels 6L and 6R are rotatably supported by extending the axles 7L and 7R in the left-right direction at the left and right positions on the rear end side. Yes. In these drive wheels 6L and 6R, pulleys 8L and 8R are fixed inside the axles 7L and 7R, respectively.
Endless timing belts 11L and 11R are wound between the pulleys 8L and 8R and the pulleys 10L and 10R fixed to the rotation shafts of the electric motors 9L and 9R disposed on the front side of the drive wheels 6L and 6R. Thus, the drive wheels 6L and 6R are rotationally driven at the same rotational speed as the rotational speeds of the rotating shafts of the electric motors 9L and 9R. Here, each of the electric motors 9L and 9R is provided with non-excitation actuating brakes 12L and 12R that operate the brake in a non-excited state.

At this time, if the rotation speeds of the rotating shafts of the electric motors 9L and 9R are made equal, the base 3 moves in the front-rear direction according to the rotation direction of the rotating shaft, and the rotation speed of the left driving wheel 6L is changed to the right driving wheel 6R. The base 3 turns left (or turns right) when driven at a rotation speed (or a high rotation speed) slower than the rotation speed.
In addition, when the right driving wheel 6R (or the left driving wheel 6L) is driven to rotate in the forward direction with the left driving wheel 6L (or the right driving wheel 6R) stopped, the left (or right) turning state is established. Become.
Further, when the left driving wheel 6L (or the right driving wheel 6R) is driven in reverse rotation and the right driving wheel 6R (or the left driving wheel 6L) is driven forward rotation, a super-left (or right) turning state is established. Become.

Thus, the base 3 can be made to travel in an arbitrary direction by controlling the rotational speeds of the left and right drive wheels 6L and 6R.
A support arm 15 that is inclined and extended from the front end side to the rear side on the upper surface is fixed to the base 3. A horizontal arm 16 is formed at the upper end of the support arm 15 so as to extend rearward in parallel with the base 3 to a position near the recess 4 of the base 3. On the rear end side of the upper surface of the horizontal arm 16, an operation input unit 17 for inputting the traveling direction is disposed. The operation input unit 17 includes a grip 18 that a pedestrian can hold with one finger and a six-axis force that detects the input in the XYZ axial directions applied to the grip 18 by connecting and supporting the grip 18. It consists of a sensor 19.

  Further, a band-shaped opening 21 is formed on the side surface on the front end side of the base 3 over an angle range of, for example, 300 degrees, and 90 degrees on the rear side in the horizontal direction on the inner side corresponding to the front end of the opening 21. A scanner-type range sensor 22 that measures the distance to an obstacle using a laser beam in an angle range of 270 degrees excluding the angle range is provided. Similarly, on the front end side of the horizontal arm 16, a scanner-type range sensor 23 that measures the distance to an obstacle using a laser beam in an angle range of 270 degrees excluding an angle range of 90 degrees on the rear side in the horizontal direction. Is provided.

In addition, a scanner-type range sensor 24 that measures a distance to an obstacle on a diagonally lower side in an angular range of 240 degrees excluding an upper angular range of 120 degrees is provided on the back surface side of the upper end side of the support arm 15, for example. Furthermore, a camera 25 is provided on the front end side of the support arm 15 facing the scanner range sensor 24 to acquire image information of obstacles obliquely downward and forward.
Then, the electric motors 9L and 9R are drive-controlled by the travel control device 30, as shown in FIG.

  As shown in FIG. 6, the travel control device 30 includes an arithmetic processing device 31 such as a microcomputer that is driven by a battery built in the self-propelled body 2. As shown in a functional block diagram in FIG. 7, the arithmetic processing device 31 includes a travel control unit 51, an obstacle detection unit 52, an obstacle contact determination unit 53, and a travel direction correction unit 54. Yes. As shown in FIG. 6, the arithmetic processing unit 31 includes a sensor signal input I / F 61, a speed command value output I / F 62, a rotation angle position input I / F 63, and an audio output I / F 64. Yes.

The sensor signal input I / F 61 is connected to the above-described six-axis force sensor 19 of the operation input unit 17, scanner range sensors 22 to 24, and the camera 25. In the sensor signal input I / F 61, the forces Fx, Fy, and Fz that are applied from the six-axis force sensor 19 in the three-axis directions of the X, Y , and Z axes, and the three axes of the X, Y , and Z axes. Read around moments Mx, My and Mz. The sensor signal input I / F 61 reads obstacle position information output from the scanner range sensors 22 to 24 and image information captured by the camera 25.

  The speed command value output I / F 62 outputs the speed command value generated by the travel control unit 51 to the motor drivers 65L and 65R to which power is supplied from the battery built in the self-propelled body 2 that drives the electric motors 9L and 9R. To do. The rotation angle position input I / F 63 reads the rotation angle position information output from the encoders 66L and 66R that detect the rotation angle positions of the electric motors 9L and 9R, and outputs the information to the travel control unit 51.

The audio output I / F 64 outputs, for example, alarm information including audio output when the obstacle detection unit 52 detects the approach of an obstacle to the speaker 67.
The travel control unit 51 performs a travel control process shown in FIG. 8 by turning on a start switch (not shown), and generates speed command values for the electric motors 9L and 9R.
In this travel control process, first, in step S1, the forces Fx, Fy, and Fz applied to the X, Y, and Z axes output from the six-axis force sensor 19 of the operation input unit 17, and the X, Y, and Z axes. Read around moments Mx, My and Mz.

Then, extraction proceeds to step S2, the force Fz pedestrians requiring leading out of the force F x ~Fz input at step S1 is applied to the Z-axis for detecting whether grips the grip 18 Then, it is determined whether or not the extracted force Fz is greater than or equal to a preset gripping force threshold Fzth. If the determination result in step S2 is Fz <Fzth, it is determined that the pedestrian requiring guidance does not hold the grip 18, the process returns to step S1, and waits until Fz ≧ Fzth. On the other hand, when the determination result of step S2 is Fz ≧ Fzth, the process proceeds to step S3.

  In step S3, electric power is supplied to the non-excitation actuating brakes 12L and 12R of the electric motors 9L and 9R to release the brake, and then the process proceeds to step S4. In step S4, among the forces Fx to Fz and moments Mx to Mz input in step S1, the force Fy in the Y-axis direction, which is the force in the front-rear direction involved in the forward / reverse travel of the self-propelled body 2, and the self-propelled body 2 The moment Mz about the Z-axis that is involved in the turning of the vehicle is calculated.

Next, the process proceeds to step S5, where the virtual mass of the self-propelled body 2 is M, the following formula (1) is calculated based on the force Fy in the Y-axis direction, and the forward / reverse speed of the self-propelled body 2 V [m / s] is calculated, and the calculated forward / reverse speed V is updated and stored in the forward / reverse speed storage unit formed in the RAM or the like, and then the process proceeds to step S6.
V = ∫ (Fy / M) dt (1)

In step S6, when the virtual inertia moment about the Z-axis of the self-propelled body 2 is Irz, the calculation of the following equation (2) is performed based on the moment Mz about the Z-axis, and the turning speed ω [rad / s] And the calculated turning speed ω is updated and stored in the turning speed storage unit formed in the RAM or the like, and then the process proceeds to step S7.
ω = ∫ (Mz / Irz) dt (2)

In step S7, based on the calculated forward / reverse speed V and turning speed ω, a correction process described later is performed with reference to the risk map shown in FIG. 10, and then the process proceeds to step S8.
In step S8, the following formulas (3) and (4) are calculated based on the forward / reverse speed V calculated in step S5 and the turning speed ω calculated in step S6, and the wheel peripheral speeds of the drive wheels 6L and 6R are calculated. V _L [m / s] and V _R [m / s] are calculated.
V _L = V + Lw · ω / 2 (3)
V _R = V−Lw · ω / 2 (4)
Here, Lw is the distance [m] between the left and right drive wheels 6L and 6R.

Then, the processing proceeds to step S9, based on the calculated wheel peripheral velocity _{V L} and _{V R} of the drive wheels 6L and 6R to calculate the speed command value _{V ML} and _{V MR} of the electric motor 9L and 9R, the calculated speed command The values V _ML and V _MR are output to the motor drivers 65L and 65R via the speed command value output I / F 62.
The obstacle detection unit 52 reads the scan angle and the distance detection value measured by the scanner range sensors 22 and 23, and calculates the position of the obstacle and the distance to the obstacle. Here, when there are a plurality of obstacles, the position and the distance to the obstacle are calculated for each obstacle.

  The obstacle contact determination unit 53 reads the forward / reverse speed V updated and stored in the forward / reverse speed storage unit and the turning speed ω updated and stored in the turning speed storage unit and detected by the obstacle detection unit 52. Based on the position and distance of the obstacle, the possibility of the self-propelled body 2 coming into contact with the obstacle is determined. The obstacle contact determination unit 53 calculates various traveling trajectories when the position and distance of the obstacles, the forward / reverse speed V and the turning speed ω of the self-propelled body 2 are changed, and among the calculated traveling trajectories. 9 is extracted, and a distance d between the traveling body 2 and the obstacle on the travel locus is calculated as shown in FIG. 9, for example.

When d> Du based on the calculated distance d and a threshold distance Du for determining a preset risk level, the risk level u is set to 0. When d ≦ Du, the following equation (5) is set. The risk u is calculated by performing the following calculation.
u = (Du−d) / Du (5)

  Further, the risk map shown in FIG. 10B is calculated based on the travel trajectory that may come into contact with the obstacle and the risk u, and is stored in the risk map storage unit formed in the RAM or the like. This risk map shows that when the self-propelled body 2 has a plurality of obstacles such as poles on both sides in the traveling direction of the self-propelled body 2 as shown in FIG. The ratio is formed with ω. That is, when the horizontal axis represents the turning speed ω and the vertical axis represents the forward / reverse speed V, in FIG. 10 (b), the white area represents a region with a low risk u, and the hatched portion represents the risk u. Represents a high region. In this risk map, since the ratio is set by the ratio of the forward / reverse speed V and the turning speed ω, the risk is the same at each point on the radial line around the origin. For this reason, the degree of risk can be adjusted by the angle θ in the circumferential direction around the origin.

In the traveling direction correction unit 54, the forward / reverse speed V updated and stored in the forward / reverse speed storage unit and the turning speed ω updated and stored in the turning speed storage unit are read and stored in the risk map storage unit. The travel direction is changed by reading the present risk level map and performing correction processing for correcting the forward / reverse speed V and the turning speed ω according to the risk level.
In this travel direction correction processing, the points on the risk map represented by the forward / reverse speed V and the turning speed ω calculated based on the instruction information input from the operation input unit 17 are within the low risk area. In some cases, it is possible to travel at the forward / reverse speed V and the turning speed ω and allow the traveling as it is, but when it is in a high-risk region, the forward / reverse speed V and the turning speed ω It is impossible to travel, and the speed is corrected to a low risk level.

  That is, in the state of FIG. 10B, when point B is instructed by the forward / reverse speed V and the turning speed ω, the point B is located in a high risk area on the left side in the traveling direction, so the angle θ Is increased so that the turning speed ω is corrected so as to be an area where the degree of danger is small. Conversely, when point C is instructed by the forward / reverse speed V and the turning speed ω, the point C is located in a high risk area on the right side in the traveling direction, so the angle θ is reduced and the risk is small. The turning speed ω is corrected so as to be in the region.

Next, the operation of the above embodiment will be described.
Now, when a start switch (not shown) is in an OFF state, the electric power of the battery built in the self-propelled body 2 is not supplied to the traveling control device 30 and the motor drivers 65L and 65R, and the electric motors 9L and 9R are stopped. In addition, the non-excitation actuated brakes 12L and 12R are in a brake actuated state without being supplied with electric power, and the traveling of the self-propelled body 2 is stopped.
When the start switch is turned on from the traveling stop state of the self-propelled vehicle 2, power is supplied from the battery built in the self-propelled vehicle 2 to the traveling control device 30 and the motor drivers 65L and 65R, and the self-propelled vehicle 2 travels. It becomes possible.

  At this time, power is supplied to the travel control device 30, and the travel control unit 51 starts executing the travel control process shown in FIG. At this time, when a pedestrian requiring guidance does not hold the grip 18 of the operation input unit 17, the Z-axis direction force Fz output from the six-axis force sensor 19 of the operation input unit 17 is substantially “0”. Yes, because it is less than the gripping force threshold value Fzth, it waits until Fz ≧ Fzth in step S2. For this reason, the speed command values for the electric motors 9L and 9R are not output, and the self-propelled body 2 maintains the stopped state.

When the self-propelled body 2 is in a stopped state, a pedestrian who is difficult to autonomously walk, such as a color-blind person who needs guidance, stands behind the self-propelled body 2 so that the lower limbs are stored in the recess 4 on the rear side of the self-propelled body 2. When the grip 18 of the operation input unit 17 is gripped by hand, the force Fz in the Z-axis direction having a value larger than the gripping force threshold Fzth corresponding to at least the weight of the hand is output from the six-axis force sensor 19.
Therefore, in the travel control process of FIG. 8, the process proceeds from step S2 to step S3, and actual travel control is started. At this time, a case where no obstacle is detected by the obstacle detection unit 52 will be described.

When the pedestrian inputs the direction he wants to move while holding the grip 18, the forces Fz, Fy and Fz applied to the X, Y and Z axes are output and the Z, Y and Z axes are rotated. Moments Mx, My and Mz are output.
At this time, when the pedestrian moves forward, the force Fy in the Y-axis direction is output by pushing the grip 18 forward. For this reason, the forward / reverse speed V having a positive value is calculated according to the above-described equation (1) based on the force Fz (step S5). At this time, since the grip 18 is not rotated, the moment Mz around the Z axis is not generated, and the turning speed ω calculated according to the above-described equation (2) is “0” (step S6).

In this case, since the rotation speed ω is "0", the above-mentioned (3) and (4) the wheel peripheral velocity V _L and V _R of the drive wheels 6L and 6R is calculated by the equation equal to each other forward and reverse speed V, and the mutually equal speed command value for the electric motor 9L and 9R on the basis of these wheel peripheral velocity V _L and V _R are calculated, the motor driver 65L and the speed command value via the speed instruction value output I / F 62 It is output to 65R (step S7).

For this reason, when the electric motors 9L and 9R are rotationally driven by the motor drivers 65L and 65R according to the mutually equal speed command values, the self-propelled body 2 goes straight forward.
On the other hand, when a pedestrian applies a force that rotates the grip 18 forward while rotating the grip 18 in the clockwise direction, for example, a force Fy applied in the Y-axis direction and a moment Mz about the Z-axis corresponding thereto are expressed as a six-axis force sensor. 19 is output.

For this reason, in step S7, a positive turning speed ω is calculated based on the moment Mz about the Z-axis, and based on the turning speed ω and the forward / reverse speed V calculated in step S6, by performing the (3) calculation of the formula and (4), the wheel peripheral velocity V _L of the left drive wheel 6L is faster than the forward-reverse speed V, the reverse speed before the wheel peripheral velocity V _R of the right drive wheel 6R Slower than V. Then, the speed command values corresponding to these wheel peripheral velocity _{V L} and _{V R} is outputted to the motor driver 65L and 65R via the speed instruction value output I / F 62. For this reason, when the electric motor 9L is driven at a higher rotational speed than the electric motor 9R, the self-propelled body 2 moves forward while turning right.
Thus, when there is no obstacle in the traveling direction of the self-propelled body 2, the self-propelled body 2 travels freely according to the traveling direction instruction and the turning instruction input to the grip 18, as described above. be able to.

  However, in the self-propelled body 2, the scanner range sensor 22 is disposed at the tip of the base 3, and the scanner range sensor 23 is also disposed at the upper end of the support arm 15. Therefore, the scanner range sensor 22 detects an obstacle in the fan-shaped area A1 in FIG. 5 in the horizontal direction close to the running surface, and the scanner range sensor 23 in FIG. 5 in the horizontal direction close to the chest position of the pedestrian. An obstacle in the fan-shaped area A2 is detected. As described above, since the scanner-type range sensors 22 and 23 scan the horizontal plane with the laser beam, by measuring the time from the laser beam emission angle and the emission time to reflection and return to the obstacle, Can be detected. Therefore, the width of the obstacle viewed from the self-propelled body 2 can be detected by the scanner range sensors 22 and 23.

  When the obstacle detection unit 52 detects an obstacle, the obstacle contact determination unit 53 determines whether or not the obstacle contacts the self-propelled body 2. That is, for example, when the scanner-type range sensor 22 detects, for example, a pole-shaped obstacle P1 on the right side of the traveling direction of the self-propelled body 2, as shown in FIG. The travel locus of the self-propelled body 2 can be predicted from V and the turning speed ω, and conversely, the trajectory L1 of the obstacle P1 viewed from the self-propelled body 2 can be predicted. When the trajectory L1 of the obstacle P1 intersects the shape of the self-propelled body 2, the obstacle P1 may contact the self-propelled body 2, and the trajectory L1 does not intersect the shape of the self-propelled body 2. In this case, there is no possibility that the obstacle P1 comes into contact.

  And when there exists a possibility that the obstruction P1 may contact the self-propelled body 2, the distance d of the obstruction P1 and the self-propelled body 2 on the track | orbit L1 is calculated. When the calculated distance d is greater than or equal to the preset threshold distance Du, the risk u is set to “0”, and when the distance d is less than the threshold distance Du, the risk is calculated according to the above-described equation (5). u is calculated. The risk u at this time approaches “1” as the distance d becomes shorter than the threshold distance Du and approaches zero. Therefore, the contact between the obstacle P1 and the self-propelled body 2 is avoided by correcting the forward / reverse speed V and the turning speed ω before the danger level u becomes “1”. In this case, the traveling of the self-propelled body 2 can be stopped by setting the forward / reverse speed V to “0”, and the traveling direction of the self-propelled body 2 can be changed by correcting the turning speed ω. The vehicle can travel while avoiding contact between the self-propelled body 2 and the obstacle P1.

  On the other hand, as shown in FIG. 10A, when there are a plurality of obstacles in the form of poles, for example, on both sides in the traveling direction of the self-propelled body 2, the obstacle detection unit 52 The risk level is calculated, and the maximum value is set as the risk level. At this time, the risk level calculation unit 53a of the obstacle contact determination unit 53 calculates various risk levels shown in FIG. 10B by calculating various forward / reverse speeds V and turning speeds ω of the self-propelled vehicle 2. The calculated risk map is stored in the risk map storage unit.

  In the risk level map shown in FIG. 10 (b), the horizontal axis represents the turning speed ω, and the vertical axis represents the forward / reverse speed V, which represents the degree of risk corresponding to the speed of the self-propelled vehicle 2. As shown in FIG. 10A, the side surface of the self-propelled body 2 approaches the left obstacle P2 at a relatively short distance, and the right side of the self-propelled body 2 is a relatively wide distance with respect to the right obstacle P3. In a certain state, the self-propelled body 2 can approach the obstacle P2 on the left side slightly, and can proceed forward diagonally to the right with respect to the obstacle P3 on the right side. Therefore, as shown in FIG. 10 (b), the risk map has a low risk area A11 at a slight angle with the origin O at the center of gravity of the self-propelled body 2 as the center. A region A12 with a relatively large angle and a low degree of danger is formed diagonally forward to the right.

  In this state, when there is an operation input for causing the self-propelled body to move forward without turning, the calculated forward / reverse speed V is a positive value and the calculated turning speed ω is 0. The coordinates represented by are the boundary positions of the regions A11 and A12. For this reason, the traveling direction correction unit 54 sets both the correction value ΔV for the forward / reverse speed V and the correction value Δω for the turning speed ω to “0”, so that the self-propelled body according to the direction instruction input from the grip 18. 2 runs straight ahead.

  However, it is assumed that there is an input for causing the self-propelled body to travel while turning left from the grip 18, and the coordinates of the forward / reverse speed V and the turning speed ω calculated based on the input are point B in FIG. Since this point B exists in the area A11 where the risk u is high, the angle θ for avoiding the risk is a large value, the correction value Δω for the turning speed ω is a large value, and the turning speed ω is a value close to substantially zero. to correct. Thereby, it is possible to travel straight ahead while avoiding the obstacle P2 on the left side.

  On the contrary, there is an input that causes the self-propelled body to run while turning right from the grip 18, and the coordinates of the forward / reverse speed V and the turning speed ω calculated based on the input are point C in FIG. 10B. Then, since the point C exists in the area A12 where the risk u is high, the angle θ for avoiding the risk is a small value, the correction value Δω for the turning speed ω is a negative value, and the turning speed ω is within the allowable range. Correct so that Thereby, it is possible to travel in all right diagonal directions while avoiding the obstacle P2 on the left side.

  Then, each time the self-propelled body 2 moves, a new risk map is calculated, so that the travel direction is corrected according to the new risk map. Accordingly, as shown in FIG. 10A, even when there are a plurality of obstacles along both sides of the traveling direction of the self-propelled body 2, the self-propelled body 2 can be traveled without contacting the obstacle. . For this reason, the pedestrian who is led by the self-propelled body 2 can also walk without contacting the obstacle.

In the above-described embodiment, the traveling locus when the forward / reverse speed V and the turning speed ω are changed is extracted, and the distance d between the traveling body 2 and the obstacle P1 on the traveling locus is calculated and calculated. The travel direction is changed by correcting the forward / reverse speed V and the turning speed ω with reference to the risk map for calculating the risk u based on the distance d and the threshold distance Du for determining the risk. However, the present invention is not limited to the above configuration, and as shown in FIG. 11 (a), there are a plurality of obstacles Pa in the direction in which the self-propelled body 2 is perpendicular to the traveling direction. The arrival time map shown in FIG. 11B may be calculated.

This arrival time map calculates the time t (= d / V) until the collision by dividing the distance d on the travel locus between each obstacle Pa and the forward / reverse speed V, and calculates the calculated collision time. When t is equal to or less than a threshold time _tTH at which a collision can be avoided, a dangerous region is set, and when the collision time exceeds the threshold time _tTH , a safety region is set for various forward / reverse speeds V and turning speeds ω. The arrival time map shown in FIG. 11B is calculated by repeating the above process.

Then, referring to the arrival time map on the basis of the forward / reverse speed V and the turning speed ω during traveling, it is determined whether it is in the danger area A21 shown in the hatched area or in the safety area A22 shown in the white map, When the point A on the arrival time map represented by the speed V and the turning speed ω is within the danger area A21, the nearest point A ′ of the safety area A22 is selected.
At this time, if the forward / reverse speed V ′ at the selected point A ′ is too lower than the point A in the danger area A21, the forward / backward speed V is constant with respect to the selected point A ′ and the turning speed ω is increased. Select point A ″.

Thus, by selecting the point A ″, the margin to the dangerous area A21 of the forward / reverse speed V is increased, and it is possible to more smoothly avoid traveling to the dangerous area A21.
Specifically, the travel control unit 51 shown in FIG. 7 executes the travel control process shown in FIG.
In this travel control process, referring to the arrival time map shown in FIG. 11 (b) based on the forward / reverse speed V and the turning speed ω calculated by the process of step S7 in the travel control process of FIG. It is determined whether or not the V and the turning speed ω need to be corrected. When the correction is necessary, the process is changed to step S10 for correcting the forward / reverse speed V and the turning speed ω.

As shown in FIG. 13, in the correction process in step S10, first, in step S11, it is determined whether or not the intersection A of the calculated forward / reverse speed V and the turning speed ω is within the danger area A21. When A is in the safety area A22, the correction process is terminated as it is, and the process proceeds to step S8.
On the other hand, if the determination result in step S11 is that the intersection point A is in the dangerous area A21, the process proceeds to step S12, and the point A ′ in the nearest safety area A22 is selected from the intersection point A, and then the process proceeds to step S13.

  In this step S13, the deviation ΔV of the forward / reverse speed V at the intersection A and the point A ′ is calculated, and then the process proceeds to step S14 to determine whether or not the calculated speed deviation ΔV is equal to or larger than the set value ΔVs. When ΔV <ΔVs, the process proceeds to step S15, where the forward / reverse speed V ′ and the turning speed ω ′ at the point A ′ are set as the target forward / reverse speed V and the turning speed ω, and then the process proceeds to step S8.

  On the other hand, when the determination result in step S14 is ΔV ≧ ΔVs, the process proceeds to step S16, and a point (V ′, ω ′ ± Δω) obtained by adding or subtracting a predetermined value Δω that is a safe direction based on the current turning speed ω ′ is newly added. Then, the process proceeds to step S17, where the forward / reverse speed V ″ and the turning speed ω ″ of the correction point A ″ are set as the target forward / reverse speed V and the turning speed ω, and then step The process proceeds to S8.

  Therefore, when the arrival time map is referred to based on the forward / reverse speed V and the turning speed ω calculated in steps S5 and S6 by executing the correction process shown in FIG. 13, as shown in FIG. 11B. In addition, when the intersection A exists in the danger area A21, the nearest point A ′ of the safety area A22 is selected. At this time, when the speed deviation ΔV between the forward / reverse speed V ′ of the selected point A ′ and the forward / backward speed V of the first intersection A is less than the set value ΔVs, the point A ′ is set as a correction point as it is. The forward / reverse speed V ′ and the turning speed ω ′ at the point A ′ are set as the target forward / backward speed V and the turning speed ω.

However, as shown in FIG. 11 (b), when the forward / reverse speed V ′ at the correction point A ′ decreases greatly and the speed deviation ΔV is greater than or equal to the set value ΔVs, the turning speed ω ′ at the correction point A ′ A correction point A ″ obtained by adding a predetermined value Δω of the following sign is selected, and the forward / reverse speed V ′ and the turning speed ω ′ at the selection point A ″ are set as the target forward / reverse speed V and the turning speed ω.
Thus, by selecting the correction point A ″, the margin of the forward / reverse speed V to the dangerous area A21 is increased, and it is possible to more smoothly avoid traveling to the dangerous area A21.

  Moreover, in the said embodiment, although the case where it drive | worked avoiding the obstacle of the horizontal direction of the self-propelled body 2 was demonstrated, it is not limited to this. For example, as shown in FIG. 14, a scanner range sensor 70 that scans a laser beam with respect to a vertical plane is arranged in front of the self-propelled body 2, and the floor surface is scanned by the scanner range sensor 70. Then, the distance information detected by the scanner range sensor 70 is input to the floor surface determination unit 71. The floor surface determination unit 71 determines whether or not the floor surface is a flat surface. That is, the distance to the floor surface is calculated from the sine relationship between the scanning angle θ detected by the scanner-type range sensor 70 (with θ = 90 degrees directly below the sensor) and the detection distance, and the calculated floor surface distance is long. When it becomes, it can be judged that there is a step which falls. By correcting the measurement distance at this time to the floor surface height and judging the corrected point as an obstacle, the traveling control for avoiding the step is performed in the same manner as the above-described embodiment for avoiding the obstacle on the horizontal plane. Can do.

Moreover, in the said embodiment, although the caster 5 was installed in the front side as the self-propelled body 2 and the drive wheels 6L and 6R were provided in the rear wheel side, it was not limited to this, Drive wheels may be arranged at the left and right positions, and casters may be arranged at the rear wheel side.
Furthermore, in the above embodiment, the case where the self-propelled body 2 is driven by two wheels has been described. However, the present invention is not limited to this. By doing so, the traveling direction may be controlled. Even in this case, the travel locus can be calculated based on the steered angle of the steered wheels, and contact with an obstacle can be determined.

In the above-described embodiment, the case where the scanner range sensors 22 and 23 are applied as the obstacle detection unit 52 has been described. However, the present invention is not limited to this, and other distance measurement sensors such as an ultrasonic sensor are used. Can be applied. Further, instead of the scanner range sensor, scanning may be performed by rotating a distance measuring sensor that emits laser light in one direction in the Z-axis direction.
Furthermore, the present invention is not limited to the case where the present invention is applied to the above-described walking support device, and any traveling device such as a power assist cart having a power assist function added to a layout vehicle or the like, or a senior car that is a single-seater electric vehicle for elderly people Can be applied to.

  DESCRIPTION OF SYMBOLS 1 ... Walking support apparatus, 2 ... Self-propelled body, 3 ... Base, 4 ... Recessed part, 5 ... Caster, 6L, 6R ... Drive wheel, 11L, 11R ... Timing belt, 12L, 12R ... Non-excitation actuated brake, 15 DESCRIPTION OF SYMBOLS ... Support arm, 16 ... Horizontal arm, 17 ... Operation input part, 18 ... Grip, 19 ... Six axis force sensor, 22-24 ... Scanner type range sensor, 30 ... Travel control device, 31 ... Arithmetic processing device, 51 ... Travel Control part 52 ... Obstacle detection part 53 ... Obstacle contact determination part 54 ... Travel direction correction part 65L, 65R ... Motor driver 70 ... Scanner type range sensor 71 ... Floor determination part

Claims (9)

A self-propelled body that has a manipulation unit that can be gripped by a pedestrian who performs walking support and inputs a movement direction, and that can travel in any direction with a traveling unit, and a movement direction that is input by the manipulation input unit Travel control means for controlling the travel of the self-propelled body based on the obstacle, obstacle detection means for detecting the position of an obstacle around the self-propelled body, and position information of the obstacle detected by the obstacle detection means and determining obstacle contact determination means whether the contact with the obstacle of the self-propelled body based on a traveling direction of the self-propelled body by the travel control unit based only on the input of the operation input unit and, Travel direction correction means for correcting the travel direction of the travel control means based on the determination result of the obstacle contact determination means ,
The travel direction correction means has a risk map that represents a risk calculated based on a travel locus and distance to the obstacle by a relationship between a moving speed and a turning speed of the mobile body, A traveling device that corrects a traveling direction with reference to the risk map based on a body moving speed and a turning speed . A self-propelled body that has a manipulation unit that can be gripped by a pedestrian who performs walking support and inputs a movement direction, and that can travel in any direction with a traveling unit, and a movement direction that is input by the manipulation input unit Travel control means for controlling the travel of the self-propelled body based on the obstacle, obstacle detection means for detecting the position of an obstacle around the self-propelled body, and position information of the obstacle detected by the obstacle detection means And obstacle contact determination means for determining whether or not the self-propelled body is in contact with the obstacle based on the traveling direction of the self-propelled body by the traveling control means based only on the input of the operation input unit, Travel direction correction means for correcting the travel direction of the travel control means based on the determination result of the obstacle contact determination means,
The traveling direction correction means includes arrival time map configured hazardous area and the safe area on the basis of the arrival time for the obstacle, the arrival time map based on the moving speed and the turning speed of the self-propelled body you and corrects the traveling direction by referring to run line device. The travel control means detects a moving speed detecting means for calculating a moving speed of the self-propelled body in accordance with an input from the operation input section, and detects a turning speed of the self-propelled body in accordance with an input from the operation input section. 3. The vehicle according to claim 1, further comprising: a turning speed detecting unit, wherein the obstacle contact determining unit determines contact with the obstacle based on a moving speed and a turning speed of the self-propelled body. Traveling device. The self-propelled body has a structure in which a support arm extending while inclining rearward is formed on the upper surface on the front side of the base, and a pedestrian who supports the walking is grasped and moved on the support arm. The travel device according to any one of claims 1 to 3 , wherein an operation input unit for inputting a direction is formed. The self-propelled body has a width equal to or larger than a shoulder width of the pedestrian supporting the walking, and a recessed portion for accommodating a lower limb of the pedestrian supporting the walking is formed on the rear side, and the pedestrian follows the rear and runs. traveling device according to any one of claims 1 to 4, characterized in that. The traveling device according to claim 5 , wherein the operation input unit includes a grip portion gripped by a pedestrian and a six-axis force sensor coupled to the grip portion. The obstacle detection means has a scanner range sensor that scans in a horizontal direction in front of the self-propelled body, and scans at least a predetermined angle range in front of the self-propelled body with the scanner range sensor. The travel device according to any one of claims 1 to 6 , wherein the position of an object is detected. The self-propelled body, a front wheel caster structure of claims 1 to 7, characterized in that it comprises a pair of left and right rear drive wheels driven by the normal and reverse driven electric motor by said running control means The traveling device according to claim 1. The obstacle detecting means includes a traveling surface distance detecting unit that measures a distance from a traveling surface preceding the traveling direction of the self-propelled vehicle, and a step on the traveling surface based on measurement data detected by the traveling surface distance detecting unit. The travel device according to any one of claims 1 to 8 , further comprising a floor surface determination unit that detects an obstacle as an obstacle.

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