JPH0381172B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a three-dimensional input device for a computer. More specifically, in the offline robot teaching system currently being developed by the present inventors, the environment in which the robot is placed (objects,
A general-purpose device that can be used to directly instruct and input the position, trajectory, work points, etc. of the robot hand by applying stereoscopic vision on the playback screen of stereo images taken on-site (such as motion limiting elements). The present invention relates to a three-dimensional input device. Furthermore, the present invention relates to a three-dimensional input device that can significantly reduce restrictions on the model of a host computer.

[Prior art] 2 displayed on a display device such as a CRT
Mouse, tablet, etc. are conventionally known as input devices for computers that can specify and input two-dimensional positions using a cursor displayed superimposed on a dimensional background image. When trying to specify or input a position in three-dimensional space using these input devices, it is necessary to first input the two-dimensional coordinates of the X-Y axes, and then input the coordinates of the Z-axis. is necessary. Therefore, there is a problem that the input operation becomes a complicated operation that is disconnected from the three-dimensional sense that the operator has.

Directly displays spatial positions, trajectories, etc. using the operator's three-dimensional recognition ability or senses,
Alternatively, in order to record and playback, for example, a pen that can draw freely in three-dimensional space (in an abstract sense) and a computer that continuously detects the position (especially the position of the tip) and angle of the pen are used. A means of inputting information is desired.

For example, the first
A light receiving device consisting of a photomultiplier tube 51, condensing lenses 52, 53, and a rotating disk 55 having a slit 54 as shown in FIG. A light emitting type has been proposed in which a stylus 56 that emits pulses is moved and the position of the tip of the stylus 56 is detected as an angle from a light receiving device.

Furthermore, an acoustic input device as shown in FIG. 13 has been proposed, which combines three line microphones 57 orthogonal to each other and a stylus pen 58 with a transmitter. Furthermore, as shown in FIG. 14, using three joy stakes 61,
Measuring the distance from three planes 62 that are orthogonal to each other,
A dynamic input device that inputs the position signal as a position signal is also known.

In addition, as shown in FIG. 15, a one-dimensional element (vertical coordinate measuring mechanism)
An advanced two-dimensional mouse with 64 added has been proposed (see Japanese Patent Laid-Open No. 62919/1983).

On the other hand, although not for computer input, devices similar in mechanical features to the input device of the present invention include a radial drilling machine with a digital position reading device based on cylindrical coordinates, and a three-dimensional precision machine with an articulated link arm. Measuring devices (for example, MODEL VSC-07 manufactured by Kosaka Laboratory Co., Ltd.) are known.

[Problems to be Solved by the Invention] Since the light emitting type device needs to detect light from three directions at the same time, care must be taken to ensure that the tip of the pen does not get in the shadow of the hand or the pen in the measurement space. In addition, if there is a model or other object in the space that will obstruct the light, you will need to change the orientation many times and take measurements, and then connect the results to get a complete picture. Therefore, there are problems in that the input operation is complicated and the reliability of recording of the input signal obtained is low.

The acoustic type and dynamic type input devices have problems in that the effective spatial indication range is narrow, the installation area of the device is large, and it is difficult to operate.

The advanced two-dimensional mouse has a very small vertical pointing range and can only be used for limited purposes as a three-dimensional input device.

As mentioned above, the conventional three-dimensional input device is functionally insufficient for use in the offline robot teaching system using stereo images intended by the present inventors.

Note that the signals transmitted from the conventional three-dimensional input device are generally transmitted with a transmission code specially determined between the three-dimensional input device and the dedicated host computer on a dedicated serial or parallel signal line. Therefore, when trying to connect to other models, there are many restrictions on the port to which the signal line can be connected, and even if the signal line can be connected, there is the problem that a separate program must be created to decode the transmitted code.

The present invention provides a general-purpose three-dimensional input device that can be used in the teaching system, has good operability, has a small installation area, has a large display space, and can be easily connected to many types of computers. is intended to provide.

[Means for solving the problems] The three-dimensional input device for a computer according to the present invention has the following features:
a fixing part that can be detachably fixed to a stationary base;
a series of arms connected to each other so as to extend sequentially from the fixed part via rotatable joints; and an input input device connected to the distal ends of the series of arms and provided with at least a part of the operating device of the host computer. an indicator for indicating a point; a detector provided at each joint for detecting a relative angular displacement between elements connected to the joint; and an angular displacement detected by the detector. a converting means for converting the input point into a position signal of an input point on a predetermined three-dimensional coordinate; and a transmitting means for sending the position signal from the converting means and a signal indicating the state of the operating section to the host computer side. It is a structural feature that it has.

[Operation] To use the three-dimensional input device of the present invention, hold the pointing grip in your hand and specify an arbitrary point on a stationary base or draw a trajectory. During these operations, each detector detects the angular displacement of the joint in response to instructions from the host computer or button operations on the instruction grip, and these angular displacements are converted to predetermined three-dimensional coordinates by the conversion means. The coordinates are then sent to the host computer and input.

In the device of the present invention, there is only a series of relatively articulated arms interposed between the stationary base and the pointing grip. Therefore, the connected postures of these arms flexibly follow the movement of the pointing section, and hardly get in the way when the operator moves the pointing section and changes its direction.

In addition, the position, trajectory, etc. can be freely instructed and input within an extremely wide spatial range until the series of arms is fully extended.

Further, since the mechanical part of the device of the present invention can be fixed onto a stationary base such as a desk using a fixed part such as a clamp, the actual space it occupies is extremely small.

In addition, since the coordinate conversion means was provided on the input device side,
This has the advantage of reducing the burden on the host computer.

In addition, the message as an input signal is processed using a character code of numbers (from "0" to "9") such as JIS C 6220.
A means to create a decimal representation and a message in JIS C 6361
By providing means for transmitting data via a serial interface such as JIS C 6360, it is possible to connect to any computer.

[Example] Next, the apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view showing one embodiment of the device of the present invention, FIG. 2 is an explanatory diagram showing the operating sequence of the device shown in FIG. 1, and FIG. Perspective views schematically showing relationships with numerical values, 4th to 5th
The figures are a side view and a plan view of the mechanism section shown in FIG. 1, FIG. 6 is a block diagram showing an example of the basic configuration of the logic circuit section used in the present invention, and FIG. FIG. 8 is a block diagram showing an example of the hardware configuration of the logic circuit section used in the device of the present invention.
9 to 11 are flowcharts showing one embodiment of the operation of the logic circuit section of the device of the present invention.

The device of the present invention shown in FIGS. 1 and 2 consists of a mechanical section 1 that functions as an input pen or a mouse, and a personal computer (hereinafter referred to as a personal computer) based on signals from the mechanical section 1.
(4 in Figure 2) for sending coordinate signals to a host computer, and in the device shown in Figure 1, a logic circuit unit 2 for displaying an image based on signals from a personal computer. A CRT display device (hereinafter referred to as CRT) 3 is provided.

The logic circuit section 2 is 3 in the embodiment shown in FIG.
The board 2a, 2b, 2c is housed in a rack 6 on which a CRT 3 is mounted.

The mechanism section 1 has a function as a pen or a mouse for performing three-dimensional input like the various conventional devices shown in FIGS. 12 to 15, but in the present invention, a multi-joint mechanism is used. The case shown in FIG. 1 employs a five-axis joint mechanism as described below.

First, the mechanical section will be explained with reference to FIGS. 3 to 5. In the figure, Z indicates the rotation axis of the joint, and θ indicates the rotation angle.

The mechanism section has a clamp 7 for fixing it to a table 5 as a stationary base. The clamp 7 has a vertical axis Z ₀ via a first joint 8 and a second joint 9.
and a first arm 10 that is rotatably connected around a horizontal axis _Z1 , and the first arm 1
A second arm 12 that is rotatable around a horizontal axis Z ₂ is connected to the tip of the arm 0 via a third joint 11 . Note that the arm and the like may be hung from above, such as from the ceiling.

The arms 10 and 12 shown in FIGS. ₃ and ₄ are made of steel pipes (diameter 18
mm, wall thickness 0.5 mm), but is not limited to this.

With the above configuration, the first arm 10 and the second arm 1
2 can move freely in a vertical plane 13 perpendicular to the surface of the table 5 and rotating about said vertical axis Z ₀ as shown in FIG.

At the tip of the second arm 12, a fourth joint 14 rotatable around the central axis _Z3 of the second arm 12 and a fifth joint ₁₅ rotatable around an axis _Z4 perpendicular to the central axis Z3 are connected. Indicator grip 16 with a length (height h from center of rotation to tip P) of approximately 250 mm
is provided.

Therefore, the tip P of the pointing grip 16 moves on the spherical surface 17 shown in FIG.

The joints are made of materials with low frictional resistance, such as bearing bushes made of fluororesin, polyacetal, polycarbonate, nylon, etc., ring-shaped spacers, etc., so that the operating grip 16 can be moved smoothly by hand. It is preferable to use a sliding part, but if necessary, as long as it does not impair smooth operability,
A suitable amount of frictional resistance may be applied to all or some of the joints, or a balancing means may be provided to balance the weight of the arms or the like.

In each of the joints, rotary encoders _R1 to _R5 are installed coaxially with the axis of rotation of the joint by coupling or the like, as detectors for detecting the displacement angle between the front and rear elements of the joint, that is, the rotation angle of the joint. It is being

Note that a ball joint type joint capable of rotating around two axes may be used as the joint, but in that case, it is necessary to provide two angular displacement detectors.

Any detector that can detect the above-mentioned angular displacement can be used, including rotary,
In addition to digital detectors such as encoders,
analog type, e.g. potentiometer,
Resolvers and the like are also used.

The instruction grip 16 is equipped with two pushbutton switches B ₁ and B ₂ as part of the operating mechanism of the personal computer (4 in Figure 2), and one rotary encoder with 2400 pulses per revolution (600 pulses). double count,
Dial D (adding 16 bits) is provided, and as described later, the operator can fix and release the indicated point while operating the indicating grip 16, and select the menu displayed by the computer. It is configured to be able to execute various commands such as. This configuration greatly improves the operability of the input device.

The dial D may be the same as the angular displacement detector of the joint, such as a rotary encoder.

In other words, the pointing grip 16 is used to freely draw figures in a so-called freehand manner within the space on the table 5 and to indicate the position, and during the operation, the pointing point can be fixed or released at will. You can select from the computer menu.

In order to further improve operability, the portion of the indicator grip where the push button switch and the like are provided is rotatable around an axis in the longitudinal direction.

The rotary encoders R ₁ to _{R 5} convert the angular displacement, which is a mechanical signal of each joint, into an electrical signal and output it as a number of pulses corresponding to the amount of displacement to the logic circuit section 2 described below. do.

FIG. 6 is a block diagram showing an example of the basic configuration of the logic circuit section 2 used in the present invention.

The displacement angles at each joint detected by the rotary encoders R ₁ to _{R 5} are read, for example, in the form of electrical signals and sent to the coordinate conversion means. The coordinate conversion means calculates the three-dimensional coordinates of the tip position of the pointing grip, that is, the position of the input point, based on the read displacement angle and the known lengths of the arms 10, 12 and pointing grip 16.

As the three-dimensional coordinates, for example, three-dimensional orthogonal coordinates (mouse coordinate system) _K2 whose origin is the left front end of the table that clamps the mechanism part are adopted, but the coordinate unit and the like can be changed as desired by the operator. It may also be converted to the user coordinate system K ₁ ′ with a different direction.

Coordinate transformation from the articulated coordinate system K ₃ to the mouse coordinate system K ₂ or the user coordinate system K ₁ can be performed using various conventionally known methods, but in order to accommodate changes in the number of axes, the following matrix is used. It is convenient to do this by calculation.

Regarding coordinate conversion calculation, if we take the conversion from multi-joint coordinate system K ₃ to mouse coordinate system K ₂ as an example,
Referring to FIGS. 4 and 5, let E be the translational transformation matrix from the tip P of the pointing grip 16 to the fifth joint 15, and let the transformation matrices between each link coordinate system be A ₅ , A 4 , A 5 , A ₄ , A ₃ , A ₂ , A ₁ , the first joint and the second joint
If the translation matrix from the intersection with the joint to the mouse coordinate system _K2 is Z, then the transformation matrix T from the tip P of the pointing grip to the mouse coordinate system _K2 is T=Z A ₁ A ₂ A ₃ A ₄ A ₅ E.

Assuming that the angles of each joint are respectively θ ₅ , θ ₄ , θ ₃ , θ ₂ , and θ ₁ as shown in FIGS. Since the mouse coordinates (x, y, z) are the components of
_{Each component of _ _ _ _ _ _ _ _ _ _ _ 1} (c ₂₃ c ₄ s ₅ + s ₂₃ c ₅ ) − c ₁ s ₄ s ₅ ) + s ₁ (d ₄ s ₂₃ + a ₂ c ₂ ) + my, z=h (s ₂₃ c ₄ s ₅ − c ₂₃ c ₅ ) − (d ₄ c ₂₃ − a ₂ s ₂ ) + mz.

However, s _o = sin θ _o , cn = cos θ _o , s _ij = sin (θ _i + θ _j ), c _ij = cos (θ _i + θ _j ), and (mx, my, mz) are the axis of the first joint. These are the coordinates of the intersection of the axes of the second joint.

Note that from the mouse coordinate system K ₂ to the user coordinate system K ₁
The conversion to can be performed, for example, by conversion between ordinary orthogonal coordinate systems.

Next, a message is created based on the obtained calculation result and the signal indicating the state of the operating section.

In the transmission message to the host computer,
The calculation result of the conversion from the articulated coordinate system to the orthogonal coordinate system regarding the specified position and the respective values of the state of the two pushbutton switches and the position of the dial are
They are arranged in decimal notation using the JIS C 6220 character code and separated by commas.

FIG. 7 shows an example of the created message. ()
is the state of the operation mode, which will be described later, and () is the x-coordinate.
Decimal representation, () is the y-coordinate decimal representation, ()
indicates the z-coordinate in decimal notation, () indicates the state of pushbutton switches B1 and B2, and () indicates the state of dial D, respectively. For example, the message shown in FIG. 7 means that the coordinates are 1, 2, -3, pushbutton switch B1 is on, pushbutton switch B2 is off, and dial D reads 1000. Note that C _R and L _F indicate a return code and a line feed code, respectively.

As mentioned above, the reason for using a decimal number array is so that it can be connected to any type of host computer. In other words, when transmitting a message that is not arranged sequentially in decimal notation like the signals from a conventional mouse, but in binary numbers created in a numeric representation dedicated to a specific computer, such as the Z80A, the specified Generally speaking, it cannot be connected to computers other than the host computer because the numerical representation is different. Even if you dare to make a connection, the computer that receives the input signal would need to perform processing such as format conversion, which would place an extremely heavy burden on the computer.

In addition, as described later, the communication interface with the host computer conforms to JIS C 6361 and JIS
Preferably, this is done using the so-called RS232C, which is a subset of C6360.

Since a normal computer is equipped with only the above-mentioned interface as an external interface, if this interface is not used, the types of computers that can input signals are greatly restricted.

For the coordinate transformation and message creation, it is convenient to use subroutines in the Fortran language, for example, but other programming languages may also be used. Other parts can usually be programmed using a macro assembler language, but this is not particularly limited.

The created message is sent to the computer for input by the sending means consisting of the interface. Note that, as will be described later, commands from the host computer are also sent to the logic circuit section via the interface.

As mentioned above, the logic circuit section 2 in the device shown in FIG. In the figure, the CPU board 2a, counter board 2b, and external interface board 2c are each surrounded by broken lines.

The logic circuit section shown in FIG. 8 uses Z80A manufactured by Sharp Co., Ltd. as a CPU and is designed in accordance with the STD standard. Note that the STD standard is a subset of the international standard bus planned and proposed by Mostek and Blog in the US, and is a bus standard exclusively for the Z80.

Memory includes one 8KB ROM (2764),
Two 2KB RAM (6116) are used. Furthermore, Z80 CTC is used as a timer/counter for switch interrupts and timer interrupts, which will be described later.

In addition, for the host computer interface, it is preferable to use a serial interface such as RS232C so that connection with various computers is possible, and in this embodiment, the serial interface is also connected to the A channel of Z80 SIO. This is achieved by using Also
A baud rate generator is connected to the connection circuit between the RS232C interface and the computer to specify the communication speed.

Rotary encoder (R ₁ ~ in Figures 4-5)
To count the pulses from _R5 and dial D, six 24-bit counters (in this example, ZEN2001, manufactured by Genik Co., Ltd.) that can directly input phase A and phase B are used.
switch S, which is automatically pressed when the instruction grip is inserted into the initial value setting table 21 of the counter.
And pushbutton switches B ₁ and B ₂ also input to the general-purpose input port of the counter.

The CPU board 2a shown in FIG. 8 corresponds to a coordinate conversion means, a message creation means, and a control means for controlling their operations, and reads and outputs data from a counter board 2b and an external interface board 2c, respectively.

In addition to the above-mentioned basic configuration, the device shown in Fig. 1 has a CRT 3 placed on the table 5 that displays image signals obtained by a personal computer as described above. Based on this, a triangular pyramid-shaped cursor resembling the tip of the pointing grip 16 is displayed on the CRT 3, and the operator moves the pointing grip 16 while looking at the input position.
It is configured so that it can be operated.

In this case, the cursor is preferably a stereoscopic image whose size changes in the depth direction, like a perspective view, in accordance with the background image, and if the background image is a stereo image, it is preferable to use a stereo image cursor.

Next, the operation of the apparatus constructed as described above and the input method to the computer will be explained with reference to the flowcharts shown in FIGS. 9 to 11.

When using the apparatus of the present invention, after turning on the apparatus, the indicator grip 16 of FIG. 3 is placed on the initial value setting stand 21 to initialize each rotary encoder. User coordinate system if necessary (Fig. 1 K ₁ )
Make the following settings. In this state, the computer waits for instructions from the host computer (standby mode) (see FIG. 9).

During standby mode, the angles of the five joints (rotary encoder) are adjusted according to the flow on the left side of Figure 10.
R ₁ to R ₅ outputs), two pushbutton switches B ₁ ,
A series of operations is repeated: latching _B2 and the value of one dial D, performing coordinate transformation, and creating a message. Although it is not shown in Figure 10, when a single transmission command is received from the host computer via the RS232C interface (see Figure 8), the most recently created message is sent to the host computer. Do this once. Therefore, when the command is received, a message is sent without waiting for calculation time such as conversion. After that, the state shown in Figure 10 again,
That is, it returns to the standby mode where it waits for commands from the host computer while latching, coordinate conversion, and message creation.

If the above command is not a one-time transmission command,
When position signals are continuously sent to the personal computer, that is, when a command is issued to change the mode to mouse mode, the mode is changed to mouse mode according to the flow on the right side of FIG.

As shown in FIG. 11, in the mouse mode, the timer interrupt is set, and the three-dimensional signal described above is repeatedly sent to the host computer under the direction of the clock timer.

That is, a series of processes such as latching from the encoder, coordinate conversion, message creation, and transmission to the host computer are repeated under the control of the timer until a mode change command is received from the host computer. When a command to change the mode from the mouse mode to the standby mode is received from the host computer, the computer waits for a new command in the standby mode shown in FIGS. 9 and 10 again.

The one-time transmission command is issued, for example, when a computer program starts and it is necessary to temporarily input the position of the pointing grip, and the mouse mode change command moves the pointing grip continuously and changes its trajectory. It is used when inputting motion as a function of time, and when displaying a three-dimensional cursor according to an instruction grip.

The pushbutton switches B ₁ and B ₂ are used to freely fix or unfix the three-dimensional position signal at that point in the computer's memory during the above operations. For example, on a CRT It is used to indicate the top of a box pictured above. The dial D can be set by a computer.
This is used to select various menus displayed on the CRT3 screen, such as robot hand trajectory input, environmental input selection, or mode selection such as 3D cursor color and shape selection, as appropriate while operating the instruction grip 16. As the dial D, for example, a rotary encoder, a potentiometer, etc. can be used. In addition to the dial, a track ball, joystick, etc. may be used as the menu selection dial.

The mouse shown in FIG. 1 uses five axes of joints. The first and second joints define two directions around the base of the arm, and the third joint determines the distance from the base to the pointing grip by bending the first and second arms. In addition to largely determining the position using a three-dimensional positioning method using spherical polar coordinates, the fourth and fifth joints 1
4 and 15, the direction (two-dimensional) of the short pointing grip 16 is precisely determined.

Therefore, the pointing grip 16 has the advantage of smooth movement and good operability. For example, when using the mechanism shown in Figures 4 and 5, the 3D cursor can be moved extremely smoothly to the point you want to specify, and you can move the 3D cursor to the point you want to specify using the
-The time required for pointing is approximately 2 times compared to inputting the Y coordinate and Z coordinate twice.
~30% decrease. Furthermore, when configuring to send the three-dimensional position of the fourth joint and the angles of the fourth and fifth joints to the computer instead of the tip position of the instruction grip, display the tip P of the instruction grip on the CRT screen. For example, it is possible to show a three-dimensional image of a triangular pyramid-shaped cursor and also show the direction of its inclination, which has the advantage of clearly indicating the position of the mating member to be superimposed on the image.

Furthermore, when the device of the present invention has a multi-joint structure with 5 or more axes, the operating position of the indicating grip can be changed freely even when specifying the same point, so it can be adjusted depending on whether the operator is right-handed or left-handed. Operability is further improved by allowing instructions to be given in a convenient posture.

However, the device of the present invention is not limited to the above-mentioned five axes, and at least three axes of joints are sufficient as long as the three-dimensional position is indicated. Also, joints with six or more axes may be used.

The device of the present invention is mainly used as a relative input device such as moving a three-dimensional cursor and indicating when using stereoscopic vision, but it is also used as an absolute input device such as measuring the three-dimensional position of a model etc. It may also be used as a device.

[Effects of the Invention] The device of the present invention has a small installation area, has an extremely wide display space, is smooth and easy to operate, can operate a computer at the same time, and can be connected to many types of computers. It has the effect of being able to.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing one embodiment of the device of the present invention, FIG. 2 is an explanatory diagram showing the operating order of the device shown in FIG. 1, and FIG. Perspective views schematically showing relationships with measured values, Nos. 4 to 5
The figures are a side view and a plan view of the mechanism section shown in FIG. 1, FIG. 6 is a block diagram showing the basic configuration of the logic circuit section used in the present invention, and FIG. 7 is a diagram showing the structure created by the apparatus of the present invention. FIG. 8 is a block diagram showing an example of the hardware configuration of the logic circuit section used in the device of the present invention, and FIG.
11 is a flowchart showing an example of the operation of the logic circuit section of the device of the present invention, Nos. 12 to 1, respectively.
4 is a perspective view showing an example of a conventional three-dimensional input device, and FIG. 15 is a front view showing another example of the conventional three-dimensional input device. Main symbols in the drawings: 1... Mechanism section, 2... Logic circuit section, 3... CRT, 4... Personal computer, 5... Table, 7... Clamp, 8, 9, 11, 14,
15... Joint, 10, 12... Arm, 16...
Instruction grip.

Claims (1)

[Scope of Claims] 1. A fixed part that can be detachably fixed to a stationary base; a series of arms connected to each other so as to extend in sequence from the fixed part via rotatable joints; and tips of the series of arms. an instruction grip for instructing an input point, which is connected to the control section, and in which at least a part of the operation device of the host computer is provided as the control section; a detector for detecting a relative angular displacement of the coordinates; a coordinate conversion means for converting the angular displacement detected by the detector into a position signal of an input point on predetermined three-dimensional coordinates; A three-dimensional input device for a computer, comprising a transmitting means for transmitting a position signal obtained by the converting means and a signal indicating the state of an operating section to a host computer side. 2. The transmitting means arranges the position signal and the operating unit status signal in order in decimal format using character codes from "0" to "9", and creates a message; 2. The apparatus of claim 1, further comprising means for outputting the text via a serial interface. 3. The apparatus of claim 1, further comprising a video display device on the stationary base for displaying the obtained position of the pointing grip by the host computer. 4. The device according to claim 3, wherein the video display device displays the background and the three-dimensional cursor as stereo images.