CN1010887B

CN1010887B - Method of measuring position of robot

Info

Publication number: CN1010887B
Application number: CN88102951A
Authority: CN
Inventors: 吉田满年; 宫田隆
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 1987-05-20
Filing date: 1988-05-19
Publication date: 1990-12-19
Also published as: JPS63286705A; AU1608388A; KR880013662A; MY102208A; AU611149B2; CA1323699C; KR940000366B1; CN88102951A

Abstract

There is disclosed a position detection method of a robot which provides two incremental position transducers mounted to a robot axis in interlocked relationship with each other and rotatably to produce pulse signals having the number different from each other in response to a moving distance of the moving robot axis and detects a difference between the numbers of pulses produced from the position transducers to detect the position of the robot. Further, a difference of the pulse number between reference pulses produced from the two position transducers at any position of the moving robot axis is calculated and the pulse number of a next reference pulse from a reference position is then calculated, a position of the robot axis is calculated. Accordingly, the moving distance necessary for detection of the reference point can be greatly shortened to less than two rotations of the position transducer and the time required for detection of the reference point can be also greatly reduced.

Description

Method of measuring position of robot

The present invention relates to measure a kind of method of robot location, this method is applicable to robot, mechanical hand, machine-tool, handling machinery and similar applications.

Fig. 4 is the example of the robot location testing agency of routine.Wherein 1 is the standard shaft of robot, the 2nd, and the positional increment sensor, it is installed on the standard shaft, and the 3rd, the reference point detecting device is contained on the reference point location, and the 4th, position calculator, the 5th, controller, (comprising central processor CPU).Controller sends instruction for topworks's (not shown), the drives crankshaft motion.The positional increment sensor produces pulse signal according to the situation of standard shaft motion, is counted by location counter.When standard shaft process reference point location, the reference point detecting device just produces a detection signal and delivers to controller, and the latter then makes the counting of location counter recover initial value.

Make the machine man-hour rigidly connecting energize, can not know the position of robot standard shaft 1 in the robot location testing agency of above-mentioned routine.So, after the energized, robot standard shaft 1 at first will be to reference point detecting device 3 positions motions, and when detecting device 3 detects this robot standard shaft 1, this detecting device 3 just produces a detection signal and delivers to controller 5, and controller 5 receives that this detection signal just makes location counter rejuvenate value.In case location counter rejuvenate value just increases or reduces counting by location counter 4 at initialization values.The pulse signal that position transducer 2 produces is counted, with the position of detection machine people standard shaft 1.

More than, a kind of robot standard shaft 1 of the robot of routine is illustrated, and all robot standard shafts 1 all can be made similar operations.

Yet in the robot location testing agency of delta pulse generator as the routine of position transducer, in case cut off the ROBOT CONTROL power supply, the positional information of robot standard shaft 1 has just disappeared, thereby restive this robot.Consequently, when connecting the ROBOT CONTROL power supply, all must move to robot standard shaft 1 its reference point detecting device 3 places and make location counter 4 rejuvenate values.Thereby just have such practical problems: each detection reference need be changed the time of a few minutes; Secondly, because no matter the stop position of robot standard shaft 1 where, the detecting operation of reference point all makes robot standard shaft 1 turn back to reference point detecting device 3 once automatically, if between robot standard shaft 1 and the reference point detecting device 3 barrier is arranged, then robot standard shaft 1 will bump against on this barrier.

In order to address the above problem, application number is that 218942/1982 Jap.P. has disclosed two incremental encoders, they are locked mutually by a gear mechanism, the number of teeth of each gear all has difference each other slightly, and in the working range of robot standard shaft hunting gear, this each scrambler all is adaptive to for once produces zero-signal simultaneously.The position that these two scramblers are produced zero-signal simultaneously calls the initial point of this machine.Like this, as long as detect this position, just can determine the initial point of machine.Yet, even this method also is inadequate as the initial point detection means.

The objective of the invention is and to solve the above problems, even and if provide a kind of robot location's detection method that also can save the delta pulse generator significantly reference position detection time and robot work setup time as position transducer.

Even if another object of the present invention provides robot location's detection method of the security of a kind of move distance that also can reduce the delta pulse generator significantly the required robot standard shaft in detection machine people position as position transducer when having improved detection reference.

To achieve these goals, a kind of robot location's detection method has been proposed here, be characterized in, the positional increment sensor on the robot standard shaft of being installed in of two interlockings has been proposed, distance according to robot standard shaft motion, their rotations produce the different pulse signal of number, and on arbitrary movement position of robot standard shaft, calculating is from the poor (P of the pulse number of the reference pulse of these two positional increment sensors generations ₂I), according to i=(P ₁-P ₂I)/(P ₁-P ₂) calculate from the pulse number (i) of next reference pulse of a certain reference position, and calculate P ₁* i just can detect the position of robot benchmark.In the formula, P ₁And P ₂It is respectively the pulse number that described position transducer produced between one refunding.

In above-mentioned robot location's detection method, these two increment sensors that dispose with robot motion's standard shaft interlocked relationship produce different numbers according to the move distance of robot standard shaft pulse.On arbitrary position of the robot standard shaft that moves in the short distance, detect reference pulse, so as according to two kinds with reference to the pulse number between the pulse, calculate the position of robot benchmark immediately.So the revolution that the required move distance of detection reference can shorten to the positional increment sensor significantly is less than two circles, thus the required time of detection reference also can shorten significantly.

As mentioned above, according to the present invention, the setup time of robot work can shorten, and simultaneously the required robot standard shaft move distance of position probing also can shorten, thus the security when having improved detection reference.

Fig. 1 is for an embodiment block scheme of robot location's detection method of the present invention is described;

Fig. 2 is the sequential chart of key diagram 1 embodiment work.

Fig. 3 is the process flow diagram of key diagram 1 embodiment work.

Fig. 4 is the block scheme of the robot location testing agency of routine.

Now consult these description of drawings embodiments of the invention.

Shown in Figure 1 is the arrangement plan of robot location testing agency.Wherein, the 13rd, the driving shaft of positional increment sensor, the motion of its random device people standard shaft (not shown) and rotating.A gear that is installed on this driving shaft 13 is meshed with first reduction gearing 16, and subtracts gear 16 by first and be meshed with second reduction gearing 17, and the number of teeth of these two reduction gearing is different.Primary importance increment sensor (PLG1) 11 is installed in the rotating shaft of first reduction gearing 16, and second place increment sensor (PLG2) 12 is installed in the rotating shaft of second reduction gearing 17.The rotating shaft of the first and second positional increment sensors is connected respectively in the rotating shaft of first and second reduction gearing.Adjust the first and second positional increment sensors 11 with 12 according to the move distance of robot standard shaft and produce the pulse signal of different numbers according to first and second reduction gearing 16 and 17 number of teeth difference phase self-adaptations.The 14th, location counter.When rotating a predetermined angular, will the pulse A that location counter 14 produces be counted by sensor 11 (if moving 10 degree of sensor 11 revolutions produce a pulse, then 36 pulses of sensor 11 revolutions generation are exactly an example).The 15th, contain the controller of CPU, provide reference pulse Z by the first and second positional increment sensors 11 and 12 to it respectively ₁And Z ₂, and provide the number of the pulse A that is counted to it by location counter 14.When controller 15 detects from the reference pulse Z of the first and second positional increment sensors 11 and 12 ₁And Z ₂And during from the umber of pulse A of the first and second positional increment sensors 11 and 12, controller 15 just makes location counter 14 initialization, and simultaneously, controller 15 is according to reference pulse Z ₁And Z ₂And the calculating be scheduled to of umber of pulse A, to measure the movement position of robot standard shaft.In the case, should produce the reference pulse Z of the first and second positional increment sensors 11 and 12 in advance according to the reference position of robot standard shaft ₁And Z ₂

The work of above-mentioned this robot location testing agency will illustrate in conjunction with the sequential chart of Fig. 2 and the process flow diagram of Fig. 3.After the energized, the robot standard shaft moves to arbitrary position, 13 of driving shafts rotate along with this motion, when driving shaft 13 rotates, primary importance increment sensor 11 rotates by first reduction gearing 16, second place increment sensor 12 rotates by second reduction gearing 17, so the first and second positional increment sensors 11 and 12 produce the reference pulse Z of sequential as shown in Figure 2 ₁And Z ₂At reference pulse Z ₁And Z ₂When delivering to controller 15, location counter 14 has been counted the pulse A that produced by primary importance increment sensor 11 and A has been read in controller 15, and controller 15 is finished following operation to measure the position of robot standard shaft.

In robot standard shaft setting in motion, controller begins to detect by flow process I → II of Fig. 3 the reference pulse Z of primary importance increment sensor 11 ₁Suppose that primary importance increment sensor 11 is detecting reference pulse Z for the first time ₁The time revolution from the reference position be i-1, and the pulse Z that detects is changeed in supposition at (i-1) shown in Figure 2 ₁Afterwards to the first reference pulse Z ₂Location counter 14 count value of being read by flow process III → IV of Fig. 3 is P before ₂I, so from the reference position, reference pulse Z ₁Revolution i can be by the flow process V of Fig. 3 according to i=△ Pi/ △ PO=(P ₁-P ₂I)/△ PO calculates.Therefore, detecting the second reference pulse Z ₁The time, just can be calculated as follows out the position of robot standard shaft.

Standard shaft position=the P of robot ₁* i

In the case, detected second reference pulse Z when controller 15 ₁The time, just the count value (P of location counter 14 ₁* i) be initialized as the robot location's value that calculates above.

After this, motion along with the robot standard shaft, location counter 14 is the pulse A counting to producing from first incremental position transducer 11 just, and with the initial value addition of this count value and counter 14 or subtract each other, and adds like this or the result that subtracted has just represented the position of robot.

As mentioned above, in the present embodiment, the first and second positional increment sensors 11 and 12 are installed in respectively on the axle of first and second reduction gearing 16 and 17, first and second reduction gearing are meshed with driving shaft 13 successively by the gear of the number of teeth that differs from one another again, and driving shaft is then driven by the motion of robot standard shaft.Whenever revolving, first and second incremental position transducers 11 and 12 turn around, be sent to controller 15 by the reference pulse that they produced, when primary importance increment sensor 11 rotates predetermined angular, the pulse A that is produced by primary importance increment sensor 11 is counted by location counter 14, and its count value is delivered to controller 15.Thereby controller 15 calculates the poor (P of pulse number of the reference pulse of when the robot arbitrary position of the standard shaft first and second positional increment sensors 11 and 12 ₂I), again according to formula i=(P ₁-P ₂I)/(P ₁-P ₂) calculate from its reference position to the umber of pulse i of next reference pulse, like this, by P ₁* i just can obtain the position of robot standard shaft.

Like this, this employing positional increment sensor method of measuring robot standard shaft position can make the required move distance in detection reference position be reduced to two commentaries on classics less than position transducer significantly.Therefore, the required time of detection reference also reduces significantly, has also reduced the setup time of robot work.Because of the remarkable shortening of the required move distance in detection machine people standard shaft position, the security when making detection reference also is improved again.

In the present embodiment, only a robot standard shaft to robot is described, and certainly, similar means also is applicable to all robot standard shafts of robot.

As mentioned above, according to the present invention, a kind of like this detection machine people can be provided the method for position, it can shorten the setup time of robot work significantly, can shorten the required robot standard shaft move distance of position probing significantly, thereby the security when having improved detection reference is although adopt the delta pulse generator also can shorten the detection time of reference position significantly as position transducer.

Claims

1, the method for a kind of detection machine people position, it is characterized in that following step: it has two positional increment sensors that are installed on the robot standard shaft interlocked with one another, and can produce according to the move distance of robot standard shaft by its rotation and to have the different pulse signal of number, the poor (P of number of calculating robot's standard shaft reference pulse that these two positional increment sensors produce when movement position arbitrarily ₂I) and by i=(P ₁-P ₂I)/(P ₁-P ₂) calculate from the reference position to the umber of pulse (i) next reference pulse, P ₁And P ₂Be respectively the umber of pulse that described position transducer whenever circles and produced, calculate P again ₁* i just can obtain the position of robot standard shaft.