JP2003081598A - Power assist device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce fatigue of an operator, mistake in operation, and working time, by making the operator of a beginner and the like efficiently and accurately leaning operation skill possessed by an expert. SOLUTION: In a step 270, a point closest to a position r of a present control point is searched from a group of sampling points positioned on a carrying path indicated by sample data (expert data), and the operation force of an expert at that point is obtained. In a step 760 and a step 770, the operation force (correction) of a beginner after correcting is decided as shown. n indicates a correction factor. By means mentioned above, a value of the operation force of the beginner used for assist ability computing process (calculation of assist ability) is corrected (straighten) by a step 770 according to operating conditions of the recorded expert, so that moderate straightening force can be generated. Therefore, the straightening force supports the beginner and the like to efficiently and accurately lean the operation skill possessed by the expert.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power assist device for assisting an operating force with an assisting force determined and output based on an operating force of an operator who operates an object to be moved or whose posture is to be changed.

[0002]

2. Description of the Related Art For example, an air balancer type is known as a transportation assisting device. In the conventional air balancer type conveyance assist device, gravity compensation is performed to balance gravity, but inertia compensation related to momentum is not performed.

[0003]

Therefore, in the prior art,
The inertia compensation as described above is entrusted to the operation skill of the operator, and when a beginner or the like works, especially when changing the direction of a transported article having a large amount of exercise or the like, a large force such as arm strength is required. It was required, a heavy burden, and was not very desirable in terms of work efficiency.

The present invention has been made to solve the above problems, and an object thereof is to provide a power assist device for assisting a beginner or the like in efficiently and accurately learning an operating skill possessed by a skilled person. Is to be realized.

[0005]

Means for Solving the Problems, and Functions and Effects of the Invention In order to solve the above problems, the following means are effective. That is, the first means includes a force sensor that detects the operation force F _h of the operator to manipulate objects of the operation target to be moved or attitude change, it is determined and output based on the operation force F _h In a power assist device that assists an operating force F _h with an assisting force A, a transportation route of an object or an operating force F _h realized by an expert, an experimenter, or a subject.
And the like, based on sample data relating to the sample such as.

According to such means, by recording, for example, the operation method of an expert (the operation form of so-called tips, etc.) as the sample data, the assist force A for the operation of the beginner (operator) is recorded. When performing correction related to the operation skill, a force for correcting a beginner's operation to be close to an expert's operation (hereinafter, may be referred to as “correction force” or the like) is the assisting force A. It is possible to add (add) as a component.

[0007] In the above sample data created based on the operation of the expert, so-called "operation tips" that change depending on the work content and the characteristics of the object are optimized based on the experience of the expert. It is considered to be included in the form. Further, the above-mentioned correction force can be increased as the operation direction and the operation force of an expert and an operator (beginner etc.) differ.

Therefore, the posture and operation of the operator can be corrected by such a correction force, and the operator feels the external force (correction force). It is possible to intuitively learn "a skilled person's operation method" such as how to operate the transportation route efficiently.

Therefore, according to such means, a beginner or the like can be assisted in efficiently and accurately learning the operation skill of the expert. Further, not only the sample data of the expert but also the sample data of a large number of subjects may be statistically processed to form representative sample data similar to the above. According to such means, it is possible to operate the above means even if there is no expert with a high degree of proficiency.

Further, by providing the operation support as described above, the following effects can be expected greatly while the beginner or the like is learning the operation skill of the expert and after the learning is completed. (Effect 1) Operator fatigue is reduced. (Effect 2) Reduction of operator's operation error. (Effect 3) The working time of the operator is shortened.

The power assist device according to the above-mentioned first means does not necessarily need to be provided with means for sampling or recording sample data. The above means operates based on the recorded sample data.

The second means is the same as the above-mentioned first means, in which sample data concerning a sample, such as a transportation route of an object or an operation force F _h , which is embodied by an expert, an experimenter, a subject, or the like, is obtained. The sample data recording means for recording is provided. According to such a means, it becomes possible to record the above-mentioned sample data and generate the assisting force based on the sample data by one power assist device. Such a means is particularly effective when it is not easy to reproduce the site where the power assist device is installed in another place, or when an expert can easily go to the site.

[0013] The third means is the sample data recording means of the second means described above, every predetermined sampling period, and to record the position r and the operating force F _h on the conveying path. However, in this specification, r is a two-dimensional or three-dimensional position vector, and _Fh is a two-dimensional or three-dimensional force vector. According to such means, when the transport route of the operator and the transport route of the expert recorded in the sample data are substantially the same, the operating force F _h of the operator is recorded in the sample data. It is possible to implement a method such as generating a correction force so that the correction force becomes closer to the operation force of a skilled person. Further, whether or not the position r is substantially the same as the transportation route of the operator and the transportation route of the expert recorded in the sample data,
Alternatively, it can be used to judge which points on the transportation route correspond to which points.

A fourth means is the above first to third.
In the assist force correction means of any one of the above, either the transportation route in the route record information regarding the object operated by the operator in the past, or the current transportation route of the object currently operated by the operator. It is provided with similar transportation route selecting means for selecting the transportation route most similar to one from the plurality of transportation routes in the above-mentioned sample data collected by a plurality of samplings.

According to such means, when a plurality of the above sample data are prepared, it is possible to automatically select the transportation route suitable for the purpose and to effectively use the above sample data. it can. Alternatively, according to such means, the sample data of the expert who is the closest to the user (operator) in terms of physique, physical strength, way of taking the transportation route, or how to move the body during operation is automatically provided. Can be selected. For this reason, the operator can acquire the operation skill of an expert who is closest to himself and is suitable for himself in the shortest time. By the means of the present invention described above,
The above problems can be effectively or reasonably solved.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on specific embodiments. However, the present invention is not limited to the examples shown below. [Embodiment] FIG. 1, FIG. 2 and FIG. 3 are perspective views illustrating a power assist device 100 according to each embodiment of the present invention. The operator holds the object 10 with the hand 152 provided at the tip of the operation unit 150, and the power assist device 1
00 to move the object 10 from the placement table 20 onto the placement table 21. Hereinafter, in this embodiment, the position r and the operating force F _h are each a three-dimensional vector.

The power assist apparatus 100 is supported by a total of four substantially vertical ridges 111 fixed to the ground surface, and the respective halves 111 are connected to each other by a total of four horizontal rails 112. There is. Moving wheel 181 (x
The moving wheel 182 (for moving the directional rod) and the moving wheel 182 (for moving the y-direction rod) can move (roll) while rotating on each rail 112. The x-coordinate of the control point in the coordinate system of the present mechanical system increases or decreases by the displacement of the y-direction rod 122 rolling and moving in parallel. Similarly, the y-coordinate of the control point in this coordinate system increases or decreases by the amount of displacement that the x-direction rod 121 rolls and translates. In addition, normally, the object 10 held near the tip of the hand 152 or held by the hand 152
A control point (a point whose position is to be controlled) is fixed to the center of gravity or the like.

Since the two moving wheels 181 (for moving the x-direction rod) are connected by the x-direction rod 121,
The x-direction rod 121 and the two moving wheels 181 (for moving the x-direction rod) move while rotating in the same direction at the same rotation speed. At this time, the moving wheel 181 (for moving the x-direction rod)
Rolls on the rail 112. y-direction rods 122 and 2
The same applies to the two moving wheels 182 (for moving the rod in the y direction).

The x-direction rod 121 is received by the bearing 141, and the y-direction rod 122 is received by the bearing 142. These bearings are composed of a bearing mechanism. Since these bearings are fixed to the central base 140, the central base 140 can freely move on the xy plane as the rods move. Further, a female screw tube 143 for z-axis bearing is rotatably fixed to the central base 140 in a vertical direction so as to penetrate substantially the center thereof, and the z-axis 1 constituted by a ball screw is formed.
30 is received by the female screw tube 143 for z-axis bearing as a male screw forming a pair. Further, since the female screw tube 143 for z-axis bearing is driven by the motor 163 for moving the z-axis to rotate, the z-axis 130 moves in the vertical direction with the rotational movement of the female screw tube 143 for z-axis bearing. be able to. Usually, the position of the above-mentioned tube axis on the xy plane is selected as the control point on the xy plane.

The operation handle 1 is provided inside the operation unit 150.
A six-axis force sensor (not shown) for detecting the magnitude and direction of the operating force F _h given to 51 and a weight scale (not shown) for measuring the weight (mass m) of the object 10 are built-in. Has been done.
The detected weight (mass m) of the object 10 and the operating force F _h are
It is input to a predetermined computer (not shown) wirelessly or by wire. Further, operation switches such as an emergency stop button (not shown) are arranged on the surface (console plate) of the operation unit 150 facing the operator side. A small camera (not shown) is mounted on this surface (console plate), and the distance d from the operation unit 150 to the operator can be measured at any time.

The output torque of the motor 161 for moving the x-direction rod is transmitted to the x-direction rod drive gear 171, the x-direction rod drive shaft 172, and the two x-direction rod drive belts 173, and this output torque is transmitted in the x-direction. The moving wheel 181 for moving the rod and the x-direction rod 121 are moved (rolled) in the y-direction rod direction. The same applies to the output torque of the motor 162 for moving the y-direction rod.

FIG. 4 is a hardware configuration diagram of a motor control device 200 which constitutes a control unit of the power assist device 100 according to each embodiment of the present invention.
Are prepared logically or physically for each axis (x, y, z) of the assist device 100.

In the brushless DC motor M of FIG. 4 (hereinafter, simply referred to as “motor M”) for generating assist torque, U, from the drive circuit 213 via the current detector 215,
Motor drive currents iu, iv, i for three phases of V and W
w is supplied. However, the form (implementation form) of the present motor M is not particularly limited to a three-phase motor or the like, and any type of motor may be used. Inside the operation unit 150 shown in FIGS. 2 and 3, a force sensor 232 (FIG. 4) for detecting the magnitude and direction of the operation force H applied by the operator is provided. The force sensor 232 can be equipped with, for example, a generally commercially available 3-axis to 6-axis force sensor or the like. The motor M is provided with a rotation angle sensor (encoder) E that detects a motor rotation angle, and the CPU 210 determines the rotation angle of the motor M based on a predetermined output signal of the motor M output by the rotation angle sensor E. Calculate.

The motor control device 200 includes a CPU 210,
It comprises a ROM 211, a RAM 212, a drive circuit 213, an input interface (IF) 214, a current detector 215 and the like. The drive circuit 213 is composed of a battery (not shown), a PWM converter, a PMOS drive circuit, etc.,
The chopper control converts the drive current into a sine wave and supplies the electric power to the motor M.

The motor control device 200 then controls the operating force H, the rotation angle of the motor M, and the motor drive current i.
u and iv are input to the CPU 210 via the input interface (IF) 214, and the current command value is determined by a predetermined torque calculation from these input values. The input interface (IF) 214 is a personal computer (PC) 25.
It also has an interface with 0, so that it can read and update the database, or input various parameters and commands (commands) as necessary.

FIG. 5 is a control block diagram illustrating a basic control system of the power assist device 100 according to each embodiment of the present invention. For example, the above-described motor 161, motor 162, or motor 163 can be controlled by such a control method. The present invention is made to rationally control the power assist device 100 as described above, and the present invention mainly relates to the operating force F.
_The present invention relates to various calculation means for realizing the assist calculation unit 400 of FIG. 5 for calculating the assist force A on the basis of _h on a computer system (not shown).

FIG. 6 is a general flow chart illustrating the procedure for executing the operation storage mode of the power assist device 100. In this flowchart, first in step 510, A / D conversion of analog signals of the operation force F _h obtained from the force sensor into a digital signal.

Next, in step 520, a signal having an unnecessary frequency such as noise is removed by a known filtering process for the converted digital signal (the current value of the operating force F _h ). In step 530, it is determined whether or not the operation storage mode is currently set. If the operation storage mode is currently set (within the work pattern storage time), the process proceeds to step 540, and if not, the process proceeds to step 570.

In step 540, the current position r of the control point ("current value P" in the figure) is calculated based on the encoder output value (encoder value) input from the encoder. In step 550, the calculated position r of the control point (“current value P” in the figure) is stored in a predetermined storage area. In step 560, the current value of the operating force F _h obtained in step 520 is stored in a predetermined storage area in association with the “current value P”.

At step 570, the assisting force A is calculated according to the following equation (1).

## EQU1 ## A = αF _h (1) Here, α is a predetermined assist ratio (scalar). Note that steps 530 to 570 described above correspond to the processing of the assist calculation unit 400 in FIG.

At step 580, the assist force A = (A
_x , A _y , A _z ) based on the value of each motor 161,1
The value of the current (current command value) to be applied to 62 and 163 is calculated. In this calculation method, as illustrated in FIG. 5, for example, the current command value may be calculated in the order of “assist force A → speed command value → current command value” or “assist force A → torque”. The current command value may be calculated in the order of “command value → current command value”.

In step 590, so-called "motor control" is performed to drive the motors 161, 162, 163 by well-known chopper control or the like. However, this step 5
90 may be entirely implemented by hardware.
By executing the "operation memory mode" as described above,
It is possible to record the operation mode of the expert as “sample data” in a predetermined storage area.

FIG. 7 is a general flow chart illustrating an execution procedure of the operation assist mode of the power assist device 100. Hereinafter, in the drawings of this specification, the following symbols (subscripts) may be used. [Meaning of subscripts attached to force vector F] h-Maturity: Operating power of skilled person stored as “sample data” h First… Operating power (detection value) of beginner before correction h First_new… After correction Beginner's operating power (correction value)

In the "operation support mode", first, in step 610, the power assist device 100 is initialized. In this process, various initial inspections such as hardware check and initialization of the computer system are performed. Next, in step 620, the sample data (expert data) recorded in the above-mentioned “operation storage mode” is read into a predetermined storage area.

At step 630, the analog signal of the operating force obtained from the force sensor is A / D converted into a digital signal. Next, in step 640, a signal having an unnecessary frequency such as noise is removed by a known filtering process for the converted digital signal (current operation force value).

At step 650, the "operation force correction" subroutine which will be described later is called and executed. As a result, the value of the operation force of the beginner used in the assist force calculation process (calculation of the assist force A) is corrected based on the value of the operation force of the expert in the above sample data.

In step 660, the value of the assist force A is calculated based on the corrected beginner's operation force (correction value) in accordance with the equation (1). However, the following generalized formula (2) may be used instead of the above formula (1). As the function f of the equation (2), for example, a broadly defined monotonically increasing function having an upper limit or the like can be used, and a suitable or optimal form can be used by appropriately tuning.

## EQU00002 ## A = f ( _F.sub.h ) (2)

In steps 670 and 680, the same processing as in steps 580 and 590 described above is executed.
However, in step 670, the current command value calculation based on the calculation of the torque command value is executed in the order of “assist force A → torque command value → current command value”.

FIG. 8 is a flow chart illustrating an execution procedure of a subroutine for realizing the "operation force correction process" in the operation support mode. This subroutine is called and executed in step 650 of FIG. First, in this subroutine, the position r of the current control point (“current value P” in the figure) is calculated based on the output value (encoder value) of the encoder input from the encoder (step 710).

Next, in step 720, a point closest to the current control point position r is searched from the set of sampling points located on the transportation route indicated by the sample data (expert data), and the point is searched. Seeking the operating power of a skilled person.

In step 730, the angle θ formed by the current direction of the operating force of the operator (beginner) and the direction of the operating force of the expert determined in step 720 is calculated. Step 7
At 40, the magnitude of the angle θ is determined. If it is 90 ° or less, the process proceeds to step 760, and if not, step 750.
Move the processing to. However, these determination processes may be performed by the sign of the calculation result of the inner product of the current operating force of the operator (beginner) and the operating force of the expert. Such a method is
For example, it is particularly effective in a device that uses an orthogonal coordinate system, such as the power assist device 100 described above.

In step 750, the operation force (correction value) of the beginner after correction is set to zero. As a result, when the operation direction greatly differs by more than 90 ° with respect to the operation force of the expert, the output of the assist force A is suppressed. In steps 760 and 770, the corrected beginner's operating force (correction value) is determined as shown in the figure. However, here
n represents a correction factor, and the value of n is 0 or more and 1
The following arbitrary values can be set. Such parameter (n) may be changed according to the situation such as the skill level of the operator (beginner).

Further, when determining the correction force in step 760, the following correction term ΔF may be added as a new one item constituting the correction force.

## EQU00003 ## .DELTA.F = .kappa..DELTA.s (3) Here, .DELTA.s is a displacement vector representing the amount of positional deviation between the transportation route of the expert and the transportation route of the beginner, and .kappa. Is an appropriate constant. Alternatively, the absolute value | ΔF | of ΔF is Δs
The absolute value | Δs |

Further, even if the above step 760 is omitted (deleted) and the right side of the substitution expression of step 770 is changed to “(experienced man operation force) + (beginner operation force) × η” or the like. good. However, here, η is an appropriate positive number.

For example, according to the above means, the value of the operation force of the beginner used in the assist force calculation process (calculation of the assist force A) of the formula (1) or the formula (2) is
Step 7 according to the recorded operation mode of the expert
Since it is corrected (corrected) by 70, an appropriate correction force can be generated. Therefore, with this correction force, it is possible to assist a beginner or the like in efficiently and accurately learning the operation skill of a skilled person.

Further, not only the sample data of the expert but also the sample data of a large number of subjects may be statistically processed to form representative sample data similar to the above. According to such means, it is possible to operate the above means even if there is no expert with a high degree of proficiency.

Although the above embodiment (FIG. 8) did not refer to the amount of sample data (experienced person data), a plurality of sets of sample data were collected by sampling a plurality of times to realize the present invention. It is also possible to automatically select only one set of the most suitable sample data from the plural sets of sample data by using the similar transportation route selecting means. The determination of whether or not the transportation routes are similar can be performed by using a known information processing method such as the least square method.
According to such a means, it is possible to automatically select a predetermined transportation route suitable for the purpose and to effectively use the sample data.

Alternatively, according to such means, an expert who is close to the user (operator) can automatically think about the physique and physical strength, how to take the transportation route, and how to move the body during operation. It is possible to select sample data. For this reason, the operator can acquire the operating skill of an expert who is close to himself and is suitable for himself in a sufficiently short time.

Further, at the initialization of step 610 in FIG. 7, among a large number of sample data (experienced person data), items such as sex, age, height, weight, or various kinds of muscle strength, physical strength, etc. are used as references. Then, a set of skilled persons who are considered to have a physique close to the operator (beginner) who uses the device is obtained, and the similar transportation route selecting means is selected from the sample data of the skilled persons narrowed down to some extent. It is also possible to automatically select only one set of sample data that seems to be most suitable by using the above. By such means, the operator can acquire the operation skill of an expert who is closest to himself and is suitable for himself in the shortest time.

[Brief description of drawings]

FIG. 1 is a power assist device 1 according to an embodiment of the present invention.
The perspective view which illustrates 00.

FIG. 2 is a power assist device 1 according to an embodiment of the present invention.
The perspective view which illustrates 00.

FIG. 3 is a power assist device 1 according to an embodiment of the present invention.
The perspective view which illustrates 00.

FIG. 4 is a power assist device 1 according to an embodiment of the present invention.
00 is a hardware configuration diagram of a motor control device 200 configuring a control unit of 00.

FIG. 5 is a power assist device 1 according to an embodiment of the present invention.
The control block diagram which illustrates the control system of 00.

FIG. 6 is a general flowchart illustrating an execution procedure of the operation storage mode of the power assist device 100.

7 is a general flowchart illustrating an execution procedure of an operation support mode of the power assist device 100. FIG.

FIG. 8 is a flowchart illustrating an execution procedure of a subroutine that realizes an “operation force correction process” in the operation support mode.

[Explanation of symbols]

m ... Mass of object to be operated (scalar) _Fh ... Operating force of operator (vector) A ... Assist force output by power assist device (vector) r ... Object position (vector) α ... Assist ratio (scalar) 10 ... object 100 ... power assist device 111 ... tension 112 ... rail 121 ... x-direction rod 122 ... y-direction rod 130 ... z-axis (ball screw) 140 ... central base 141 ... bearing (for x-direction rod) 142 ... bearing (y-direction) Rod) 143 ... z-axis bearing female screw tube 150 ... Operation part 151 ... Operation handle 152 ... Hand 161 ... Motor (for x-direction rod movement) 162 ... Motor (for y-direction rod movement) 163 ... Motor (z-axis movement) 171 ... x-direction rod drive gear 172 ... x-direction rod drive shaft 173. x-direction rod drive belt 181 ... Moving wheel (for moving x-direction rod) 182 ... Moving wheel (for moving y-direction rod) 200 ... Motor control device (control unit) 232 ... Force sensor M ... Motor E ... Encoder

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyuki Suzuki             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. (72) Inventor Yuko Matsuda             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. F-term (reference) 3C007 BS04 CT03 CT04 HS27 JU16                       KS17 KS33 KV01 KX06 LU06                       LU10 LV00

Claims (4)

[Claims] 1. A has a force sensor that detects the operation force F _h the operator operating the object moving or the operation target to be attitude change, assist force which is determined and output based on the operating force F _h In the power assist device for assisting the operating force F _h by A, based on sample data regarding a sample, such as a transportation route of the object or the operating force F _h , which is realized by an expert, an experimenter, or a subject. A power assist device having an assist force correction means for correcting the assist force A. 2. A sample data recording means, which is embodied by an expert, an experimenter, a test subject, or the like, for recording sample data regarding a sample such as the transportation route of the object or the operation force F _h. The power assist device according to claim 1. 3. The power assist apparatus according to claim 2, wherein the sample data recording means records the position r on the transportation path and the operating force F _h at every predetermined sampling cycle. 4. The assist force correction means is any one of a transportation route in route record information relating to the object operated by an operator in the past, or a current transportation route of the object currently operated by the operator. 7. A similar transportation route selecting means for selecting a transportation route most similar to one of the transportation routes from a plurality of the transportation routes in the sample data collected by sampling a plurality of times. The power assist device according to any one of claims 1 to 3.