DE2906950B2 - Device for directing an external servomechanism onto a target object which has been anoed by a person - Google Patents

Description

The invention relates to a device for steering an external servomechanism onto one of one Target object aimed at person, in which the direction of rotation and inclination of the head of the person are used to determine the angular coordinates of the target object.

Such a device is known from US Pat. No. 3,769,636. This device is a mechanical one Connection provided on the one hand on the head of a person sitting in a wheelchair and on the other hand is attached to the wheelchair itself. This connection has articulated connections on which Probes are provided so that the amount and direction of rotation of the head and also its inclination can be determined. The sensors are electrically connected to a servomechanism through which the Movement of an element can be controlled.

From DE-OS 21 32 309 a device for measuring the viewing direction is known in which on the A contact lens is arranged which has at least one mirror around the eye of the observer reflect light incident on this mirror from a light source. With the help of the mirror reflected light beam can be the movement of the eye and in particular the cornea relative to a Determine the reference direction.

A similar device is from DE-OS 22 02 172 known for the automatic tracking of the pupil of an optical device with relative lateral movement between the eye pupil of an observer and the pupil of the optical device serves on the head of an observer is a first optical device and a second optical device on the optical device Device attached A light beam bundle runs between these two optical devices

ίο the pupil of the observer correctly on the pupil of the optical device is aligned, a first signal is generated by the second optical device If the observer's pupil is laterally displaced in relation to the pupil of the optical device, then this is the case

There is also a corresponding, relative shift between the first and second optical devices, whereby the second optical device a second signal different from the first signal generated and a servo device for Moving the optical device feeds When the optical device is positioned to the pupil of the eye Has been tracked by the observer, the second optical device generates the first signal through which no tracking of the optical device is effected.

A general difficulty encountered with any target position measurement is that some external object is needed as a frame of reference. This requires that some sort of Connection between the external frame of reference and

so the system for position measurement of the target object is available. In the device known from US-PS 37 69 636 is a purely mechanical connection between the A system for measuring the position of the target object and the external system, namely the wheelchair, is provided.

η This connection affects the Freedom of movement of the head of the wheelchair user. In the known from DE-OS 21 32 309 and 22 02 172 Facilities, a bundle of light rays creates the connection between the two systems. Even this increases the freedom of movement of the head to which a light source or mirror is attached limited, since the beam emanating from the head to a relatively small reception area must be addressed, which is generally not in

4 ^r > is in the same viewing direction as the targeted object.

It is therefore the object of the invention to develop a device of the type mentioned at the beginning in such a way that that a great freedom of movement of the establishment

w user and ease of use the facility are guaranteed.

This object is achieved in that to measure the direction of rotation of the head around the vertical axis responding to the earth's magnetism

r> corresponding direction of rotation measuring device is provided and the inclination of the head by an inclination measuring device which measures the deviation from the horizontal can be determined.

A particular advantage of the invention is that

W) as an external reference system, on the one hand, the earth's magnetic field and on the other hand the effect of gravity can be exploited. The amount and direction of rotation of the Head is fastened to the head of the person, responsive to the magnetic field

M determined measuring device. The inclination of the head is determined by an inclination measuring device, which is also attached to the head of the person and is responsive to gravity in a known manner.

Due to the special choice of the reference system, no mechanical connection to the reference system is required, and there are only electrical connecting lines between the measuring devices attached to the head and a servomechanism Since these lines can be designed flexibly as required, the freedom of movement of the head is increased does not affect the person

With the device according to the invention, it is also possible to determine the sizes required to control the servomechanism by directly aiming at the target object, which is generally not the case when a light beam is used as a link between the system for determining the position and the reference system

The operation of the device according to the invention is extremely simple because the free rotation of the Control measures necessary for the movement of a servomechanism are taken can. The device according to the invention can advantageously be used to actuate artificial limbs, such as B. an artificial arm can be used.

Advantageous further developments of the invention emerge from the subclaims.

The invention is described below with reference to a preferred exemplary embodiment explained in more detail on the drawings. It shows

F i g. 1 and 2 are schematic circuit diagrams of a preferred embodiment of the invention,

F i g. 3, 4 and 5 timing diagrams of some important in the circuit according to FIG. 1 and 2 occurring signals,

F i g. 6 is a flow diagram illustrating the overall operation of the circuit;

7 to 12 are flowcharts explaining the operation section by section in detail;

13 is a graphical representation for the definition in the description of occurring physical values,

F i g. 14 is a graphic representation of a target pattern and

15 is a graphic representation of a display unit.

At the beginning, the principle of the optical sighting device according to the invention will be explained with reference to FIG. The line NS shows the north-south course of the earth's magnetism. Χ— Υ— Ζ are angular coordinates, with the X and K axes defining the horizontal plane and the Z axis defining a vertical plane. The coordinates are set at the beginning, so that the standard viewing direction V O- line N S forms an initial angle of view with respect to θο.

The eyes of the operator at the origin O look at the target object located at the point W from a distance R. The point IV forms with the line NS a horizontal viewing angle θ and a vertical viewing angle Φ with respect to the horizontal plane.

Da uses the horizontal component of terrestrial magnetism to calculate the position of a target object becomes the output (cos Θ) of a direction sensor using the following Modified formula:

F ₁₁ =

Ml -F Sin I ■ Sin Φ
cos Φ

whereby

Ml = sensor output variable (cos θ)
I = magnetic inclination

When the operator looks at the target object located at the point W (x, y, z) with both eyes, the values X, Y and Z can be expressed by the following equations:

.V = Rcos Φ, sin (0, - Q _ü ) Y = Äcos Φ, ■ cos (0 | - θ ₀ )
Z = RSm Φ,

where R is the distance between O and W and can be expressed as:

R =

cos Φ Sin (θ, - Θ ₂ )

NS where a is the distance between the centers of the eyes of the operator and Θ2 as a horizontal viewing angle measured from the line when the operator looks at with one eye, the target object, the following operations are carried out for calculating the above equations:

(1) Establishing a standard viewing direction to obtain an initial viewing angle θο.

(2) Looking at a target object with both eyes to obtain a first horizontal viewing angle θι and a vertical viewing angle Φ \ .

(3) Looking at the same target object with one eye to obtain a second horizontal viewing angle θι .

1st once a standard viewing direction O- Kbestimmt and determines the positions of other target objects may be prepared by repeating the above Operatioen (2) and are calculated (3).

4 (i If an artificial arm is so steered that it moving toward the target object, the height of the target object can next be determined using the following Equation to be calculated if the length and a running vertical angle of the artificial arm

4) are known:

ZH = (/.,sin α + L ₂ s \ nß)

whereby

F ,, = horizontal component of terrestrial magnetism F = total terrestrial magnetism

L] - the length of the upper section of the artificial

Arms.
Z-2 = the length of the lower section of the artificial

Arms.
λ = the vertical angle of the top portion of the

artificial arm.
β = the vertical angle of the lower portion of the artificial arm.

Further, since the distance R can be obtained by using the third equation of (2), if the height ζ and a vertical viewing angle Φ] are known, the values X and Y can be obtained using the remaining equations of (2). In this case, the following operations are performed to calculate the above equations:

(1) Setting a standard viewing direction to obtain an initial viewing angle of 6o.

(2) Position the artificial arm on the target object to obtain a height ZH .

(3) Looking at the target object with both eyes to obtain a horizontal angle Θι and a vertical angle Φ \ .

Once a standard viewing direction has been determined and established, the positions of other target objects can can be calculated at a constant height by merely repeating the above operation (3).

The positions of various target objects are thus repeatedly calculated and sent to the control system of the artificial arm is transmitted so that the artificial arm moves by engaging the viewed Follows target objects from point to point.

Another feature of the preferred optical Sighting device according to the present invention consists of 17 types of face portions identify a target object so that 17 signals that correspond to the respective target area sections, can be switched as a substitute for 17 key switches to issue commands to an external control system. The table below shows an example of commands in which six electric motors are operated.

engine

M \ M2 Λ / 3 M4 MS Mt

Stop command 0 3 6 9 CF

Normal 1 4 7 AD base

Reverse 2 5 8 BE -

14 shows a target pattern with 17 target surface sections, to generate 17 command signals.

Fig. 15 shows a display unit of the type Glasses to visually identify the 17 types of command signals. There are 17 photodiodes on the display unit attached, each of which corresponding to the respective target area section according to F i g. 14 is arranged

In the following, the invention will be explained further with reference to the schematic circuit diagrams. As one can see from FIG. 1 seen, the sensor section 1 comprises a pair of direction sensors 1 a and 16, which detect the head rotation of a person about the vertical axis. Inclinometers Ic to Xf detect the inclination of the head. The inclinometers are of the type in which torque compensation occurs when the magnet is in motion.The direction sensors Xa and Xb are attached to the head of the person concerned and are arranged at right angles to each other.They detect an angle θ between a direction of vision and the geomagnetism in the form of the functions sin θ or cos θ.

A pair of inclinometers Ic and Xd are attached to the head to detect an inclination angle Φ of the direction sensors with respect to the horizontal axis as functions of sin θ and cos Φ, respectively.

The inclinometers Ie and if are attached to the artificial arm to detect the angles ac and β of the upper and lower portions of the artificial arm with respect to the horizontal plane as functions of sin λ and sin β.

An input control section 2 comprises an input multiplexer 2a which detects input signals from the sensor section 1 and an A / D converter 2b which converts an analog signal into a digital signal.

A data control section 3 contains a multiplexer control 3a, the selection signals for the input multiplexer -, plexer 2a generated, as well as a memory addressing device 36, the address signals for the memory section 4, where input signals are stored. An operational control 3c is also provided, which controls the memory input and operating signals

κι ®. ® ι ®ι ®, © and Derzeugt.

The memory section 4 contains four memory blocks, namely memory-O, memory-1, memory-2 and memory-H.
A data modification section 5 contains computers

ι-, 5a, Sb and 5c, which modify input data received via the direction sensors.

A position or attitude calculating section 6 contains computers 6a and 66 which calculate the sine and cosine functions, and computers 6c, 6d, 6e and 6f which calculate the distance R or the angular coordinates X, Kund Z.

An altitude computing section 7 is used to obtain the positions of various target objects having a constant altitude. The section 7 contains a computer 7a which calculates a height ZH of a target object using the input data sin α and sin β . A calculator 76 calculates a distance RH (which is equivalent to the distance R) using the calculated data ZH.

in a display section 8 amplifies the from Operation control 3c incoming operating signals to set the processing or process operating modes 0, 1, 1.1, H, H.H and S. to display.

As one can see from FIG. 2, contains a direction indicator

Vy calculation section 9 calculators 9a and 96 which determine the sine function using the data stored in the storage section 4 and the modified data coming from the data modification section 5.

A direction discriminator section 10 includes multiplexers 10a and 106 which select horizontal and vertical limit values, respectively. Sequence counters 10c and 10c / generate selection signals for the multiplexers 10, and comparators or comparators 10e and 10 / compare

the data coming from the computers 9a and 96 correspond to the horizontal and vertical limit values, respectively.

A decoder section 11 outputs 17 signals corresponding to the direction identified by looking.

The operation of the preferred optical sighting device is explained below with reference to the timing diagrams (FIGS. 3 to 5) and the flow charts (FIGS. 6 to 12) in connection with the schematic circuit diagrams (FIGS. 1 and 2) will.

If a command fi is entered into the multiplexer control 3a according to FIG. 3, the system will initialized to assume a process or processing state 0, and multiplexer Control signals, ® and © generated (see also Figs. 1 and 6). The input multiplexer 2 » samples the input signals sin θο, cos θο, sin Φ _ο and cos Φο one after the other and emits a series of analog signals ®. The signal ® is converted into a serial in the A / D converter 2b

it converted to digital signal ©

In accordance with the command gj, a memory selection signal © is generated in the operation controller 3c, see above that in the memory-O the memory section 4

is selected. The memory addressing device 3b successively generates address signals ©, ©, © and $ D from the signals © and ©, so that the serial digital signal © is stored in the memory-O.

When all the input data (which were present in the form of a serial digital signal) are stored in individual sections of the memory 0, the operation control 3c emits an operating or operation signal ®, and the calculation for modifying the input data Θο takes place according to equation ( 1) instead. Fig. 7 is a flow chart showing the processing procedure in the O process mode explained above.

As one can see from FIG. 6, the controller assumes the "waiting" state when process O is complete. If a command QD is issued to calculate the position of a target object, the process mode changes to 1, and input signals sin θι, cos θι, sin Φι and cos Φι are scanned and stored in memory 1 as in process 0, with the exception that the operation controller 3c is a signal

© emits instead of the signal © in the previous process mode. In the computer 5b , following the signal © emitted by the operation control 3c, the data from cos θι are modified. F i g. 8 is a flowchart showing the processing procedure in process mode 1 explained above.

Consider Fig. 6 again. The controller assumes the "waiting" status when process 1 is completed. If the command [D is issued again, the process mode changes to 1.1, and input signals sin Θ2, cos Θ2, sin Φ2 and cos Φ2 are scanned and stored in memory 2 in the same way as in the case of process mode 1, with the except that is emitted from the operation control 3c a signal © ® instead of the signal in the previous process mode. In the computer 5c, following the operating signal ® emitted by the operation control 3c, the data of the cos. Θ2 modified.

After a certain delay time in which the data for cos02 are modified, the computers 6a, 6b and 6c are activated so that the functions sin (θι - θο), cos (θι - θο) and R in equations (2) and (3) can be determined. After a further delay time, the computers 6d, 6e and 6 / are activated so that equations (2) are calculated. The calculated values of X, Y and Z are given to the external control system for the artificial arm to aim the arm at the target object. F i g. 9 is a flowchart showing the processing procedure in process mode Q) explained above

If (see FIG. 6) the command is given following the process 11 in order to calculate a height ZH of the target object using the data, the process mode goes to H Ober, memory selection and address signals φ, φ and φ become is generated, and input signals sin <x and sin /} are sampled and stored in the memory-H. When the data is stored, the signal ® is issued to activate the calculator 7a so that equation (3) is calculated. Fi g. Fig. 10 is a flowchart showing the above-mentioned processing procedure in the // process mode

If one looks again at FIG. 6, you can see that the control goes into the "waiting" state when process H is completed. If the command Q ±] is output again, the process mode changes to HH, and input signals sin 0 |, cos θι, sin Φι and cos Φι are scanned and stored in memory-1. The operating signal © is then emitted in order to modify the data cos θι.
After a certain delay, the

κι calculator 6a, 6b and Tb activated so that the functions sin (0, -0o), cos (0, -0o) and RH {= ZH / sm Φ,) are calculated. After a further time delay, computers 6d and 6e are activated so that equations (2) are calculated for X and Y , with i using RH as R this time. Then the values ^ Y and Y together with a constant height ZH are sent to the external control system for the artificial arm in order to direct the arm towards the target object. F i g. 11 shows the above-described process in process mode HH in the form of a flow chart.

If the command \ s \ is finally given, input signals sin θι, cos θι, sin Φι and cos Φι are sampled and stored in memory-1 in the manner explained above. The operating or operational signal © is output in order to modify the data θι, and after a certain delay time the computers 9a and 9b are modified by the signal © so that the functions sin (θι - θο) and sin (Φ1-Φ0) be determined. After a further time delay following the signal ©, a signal ® is generated and the sequence counters 10c and 10d are started.

Limit values for target area sections on a target pattern are given as sin (-25 °), sin (-10 °), SIn (IO ")

J5 and sin (25 °) are supplied for each horizontal and vertical viewing angle. These values are selected one after the other in the multiplexers 10a and 10 £>, which are controlled by the sequence counters 10c and tOd.

The data for the viewing angles coming from the computers 9a and 9b are compared one after the other, starting at sin (-25 °), with each limit value in the comparators 10e and 10 /. If the input data is found to be less than a limit value, the corresponding sequence counter is stopped. If both sequence counters are stopped, the contents of the sequence counters in the decoder section 11 are decoded into 17 output signals, and from these the output signals "0" to "9", "A" to "F" and "BASIS" are sent to a corresponding photodiode in is sent to the display unit shown in Fig. 15 to confirm the targeted or viewed target area.

If correct sighting is confirmed, the command m is given again, and the output signal is given to the external control system in order to be used for command purposes.

Fig. 12 shows a flow chart showing the above explained processes taking place in process mode 5

Although in the embodiment explained above, the system according to the invention in combination with the The mechanism of an artificial arm has been explained, of course, has application to others artificial limbs possible.

In addition 12 sheets of drawings

Claims (4)

Patent claims: 1. A device for directing an external servomechanism on a target object aimed at by a person in which the direction of rotation and inclination of the head of the person is used to determine the angular coordinates of the target object, characterized in that for measuring the direction of rotation of the head about the vertical axis on the Geomagnetism-responsive direction of rotation measuring device (la, Xb) is provided and the inclination of the head can be determined by an inclination measuring device (Xc, Xd) which measures the deviation from the horizontal 2. Device according to claim, characterized in that the direction of rotation measuring device has a pair of direction sensors (la, Xb) and the inclination measuring device has a pair of inclinometers (lc; Xd) which can be fastened to the head of the person, whereby a head posture of the person can be determined if the person is aiming at a target object 3. Device according to claim 1 or 2, characterized in that at least one additional inclination measuring device (Xd, Xc) is provided on the external servo mechanism to determine the altitude of a target object when the external servo mechanism has moved to the target object. 4. Device according to one of claims 1 to 3, characterized in that a circuit arrangement (9, 10, 11) to distinguish different sight angles is provided that each of the different Sighting angle is assigned to a certain area of a given sample field, and that when aiming at an area of the pattern field by the circuit arrangement (9,10,11) a signal assigned to this area can be generated.