JPS6283609A - Locus analyser - Google Patents

Abstract

PURPOSE:To enable the accuracy of a locus to be measured by a simple operation by sampling position information stored in a counter by a CPU every constant period and, based on the data thus obtained, performing a locus accuracy computing by the CPU. CONSTITUTION:The two-pulse signals (A, B) outputted from a pulse generator for a position feedback for a numerical control unit are turned to UP or DOWN pulses by feedback interfaces 12X and 12Y to be inputted to counters 13X and 13Y, respectively, and stored in a memory 14 as position data every sampling period Ts from a CPU 11. When an accuracy computing is conducted on the sampling data stored in the memory 14, a computing is performed in the CPU 11 by a command from a key board 15 and a result can be displayed on a CRT 18 or printed by a printer 23 both as numerical data. Similarly, a graphic display can be also outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a trajectory analyzer for measuring the accuracy of numerically controlled machines, robots, general industrial positioning devices, etc.

[Conventional technology]

To measure the accuracy of numerically controlled machine tools, a workpiece to be measured is cut each time using a measurement program, and the workpiece is run through an inspection machine or measuring device to judge the results.

This method always requires an actual cutting process, and has the disadvantage that if the measurement results are not as expected, it is difficult to determine whether the cause is mechanical or electrical.

Furthermore, the method using a two-dimensional sensor as proposed in Japanese Patent Laid-Open No. 59-79110 has the problem that the system becomes expensive.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a device that can measure the trajectory accuracy and behavior of a numerically controlled machine and the numerically controlled device itself without actually cutting or adding a measurement sensor to the machine. It is.

[Means for solving problems]

The present invention is composed of a feedback interface for at least one axis, a counter, a CPU, a memory, an input means 2 and a display means, and the position information stored in the counter is displayed in constant cycles by the CPU. The counter is sampled every 111 seconds, the data obtained is stored in the memory, the CPU calculates the accuracy of the trajectory based on the data stored in the memory, and the display means displays the calculation results as numerical or graphical information. The present invention relates to a trajectory analyzer characterized by displaying.

〔Example〕

Hereinafter, the present invention will be specifically described based on embodiments shown in the drawings.

FIG. 1 shows the configuration of the present invention, in which 1 is a locus analyzer, 2 is an X-Y block, 3 is a numerical controller,
4 is an X-Y table, 5 is an X-axis motor, 6 is a Y-axis motor, 7 is an X-axis pulse generator, 8 is a Y-axis pulse generator, 9 is an X-axis ball screw, and 10 is a Y-axis ball screw.

The numerical control device 3 is a 2-axis control to simplify the explanation.
Motor drive lines are omitted. The machine also has an X-Y table 4, and the pulse generator 7.8 is a semi-closed loop type directly connected to the motor, but it has a linear scale,
There is no problem in realizing a fully closed loop method using laser feedback, inductosin, etc.

The feedback signals FBX and FBY of the X-Y axes controlled by the numerical control device 3 are input as they are into the trajectory analyzer 1 which is an embodiment of the present invention, and based on the information set in an interactive format using the attached keyboard and CRT, The trajectory accuracy is calculated and the results are plotted on the CRT or XY profiler 2.

FIG. 2 is a block diagram showing an example of the hardware configuration of the device of the present invention, in which 11 is a CPU (microprocessor), and 12X and 12Y are X-axes.

Ylth feedback interface, 13X.

13Y are X-axis and Y-axis counters, respectively.

A memory 14 includes a program memory necessary for the operation of the CPU II and a memory for storing sampling data.

Also, 15 is a keyboard, 16 is a keyboard interface, 17 is a display interface, and 18 is a C
RT, 19 is a disk controller, 20 is a floppy disk drive, 21°25 is each R3-232
-C (serial interface), 22 is a plotter, 23 is a Centronics interface, and 24 is a printer.

In this device, when the power is turned on, the CPU 11 starts operating, and the next process to be performed is displayed in a menu on the CRT 18 driven by the display interface 17.

When the operator presses a required key on the keyboard 15, the input is input to CFull through the keyboard interface 16, and the specified processing is performed by the CPU 11.

Here, two main operations of the present invention will be explained.

(1) Sampling mode Feedback interfaces 12X (X-axis circumference), 12Y (Y-axis circumference) and 12Y (Y
After determining the direction with (for axis), counter 13X is output as an UP or DOWN pulse.

13Y respectively. Counters 13X and 13Y are C
T from PtJll, memory 14 per sampling period
is stored as location data.

Sampling of the CPU II can be done manually from the keyboard 15 or by setting the counters 13X and 13Y to specific values.
In other words, sampling is automatically started when a specific position is reached, and similarly, sampling can be stopped either manually from the keyboard 15 or automatically after the counters 13X and 13Y reach a specific value, that is, a specific position. . Additionally, when the data storage memory area overflows, sampling is automatically stopped.

Sampling data are sequentially numbered starting from number 1, making it easy to refer to sampling data and specify data when calculating trajectory accuracy.

(2) Trajectory accuracy calculation mode When performing accuracy calculations on sampling data stored in the memory 14 in advance, input necessary items such as command shape, calculation starting point, number of data, etc. from the keyboard 15 using one menu method. , the CPU 11 starts calculation, and the results can be displayed or printed on the CRT 18 or printer 23 as numerical data. Similarly, a graph display can also be output to the CRT 8 or plotter 22.

FIG. 5 shows an output example of the calculation result of the accuracy of the trajectory of a straight line, and FIG. 6 shows an example of the output of the calculation result of the accuracy of the trajectory of a perfect circle.

FIG. 3 shows a model for calculating trajectory accuracy in the case of a straight line. If a straight line connecting two points a and b from pre-sampled points is defined as an ideal straight line, the error ε of an arbitrary sampling point C.

is obtained using equation 11.

ε,=ΔX・Δy/−/ΔX +Δy Z ,−,,,
-・-・(1) Equation 0 % Figure 4 is a trajectory accuracy calculation model for circular arcs and perfect circles, and arbitrary sampling in the circular arc between the starting point a and the ending point or in the perfect circle between the starting point a and the ending point a. The error ε at point C is determined by equation (2).

ε, = −J(xt −xo)” +(yt −yo)
” -R- Formula (2) In this case, center coordinates (x6.yo)
For the radius R and the radius R, known values of the NC program to be commanded to the numerical control device are inputted from the keyboard 15. Alternatively, the center coordinates (x6.yo) and radius R can be automatically calculated from the coordinate data of several sampling points.

〔Effect of the invention〕

As mentioned above, the present invention is effective: ゛, Numerical side? ]l,
-, [-By simply connecting the position feedback signal used in the machine tool to the measuring device according to the present invention, trajectory accuracy can be measured without actual cutting or adding a sensor. Moreover, it is possible to determine whether there is a malfunction on the machine side or a malfunction on the numerical control section, and it is also possible to carry out measurements using the numerical system '4B unit alone.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the configuration of the present invention, Figure 2 is a hardware configuration diagram of a measuring device that is an embodiment of the present invention, Figure 3 is a trajectory accuracy calculation model for a straight line, and Figure 4 is a circular arc. FIG. 5 shows an example of the graph output of the measurement results in the case of a straight line, and FIG. 6 shows an example of the graph output of the measurement results in the case of a perfect circle. l: Trajectory analyzer 2: X-Y plotter 3: Numerical controller 4: X-Y table 5: X-axis motor 6: Y-axis motor 7: X-axis pulse generator 8: Y-axis pulse generator 9: X-axis pole screw 10: Y-axis pole screw 11: CPLl (microprocessor) 12X: X-axis feed bank interface 12Y: Y-axis feedback interface 13X: X-axis counter 13Y: Y-axis counter 14: Memory 15: Keyboard 16: Keyboard interface 17: Display interface 18: CRT 19: Disk controller 20: Fronopy disk drive 21. 25: R3-232-C (serial interface) 22: Printer 23: Centronics interface 24: Printer

Claims (1)

[Claims] 1. Consisting of a feedback interface for at least one axis, a counter, a CPU, a memory, an input means, and a display means, the position information stored in the counter is sampled by the CPU at regular intervals;
The data obtained thereby is stored in a memory, the CPU calculates the accuracy of the trajectory based on the data stored in the memory, and the display means displays the calculation results as numerical information or graph information. analyzer. 2. Claim 1, characterized in that the storage of sampling data is automatically started and stopped by comparing the position information set by the input means with the position data obtained by sampling the counter. Trajectory analyzer described in section. 3. Claim 1, characterized in that the storage of sampling data is automatically started and stopped by comparing the position information set by the input means with the position data obtained by sampling the counter. Trajectory analyzer as described. 4. The first aspect of the present invention is characterized in that trajectory accuracy, speed, speed ripple, overshoot/undershoot, and response time are detected and displayed in an all-digital manner as a result of accuracy calculation specified by the input means. Trajectory analyzer described in section. 5. A patent characterized in that, as a method for sampling the counter, the output of the counter is latched into registers on all axes simultaneously by a command from the CPU or a sampling clock, and then read into the CPU, thereby making the sampling timing common for each axis. A trajectory analyzer according to claim 1. 6. The trajectory analyzer according to claim 1, wherein the number of sampling axes is set and an arbitrary axis is selected from among them to calculate the trajectory accuracy. 7. The locus analyzer according to claim 1, wherein any one of an encoder, a magnetic encoder, a linear scale, an inductosin, a laser feedback, and a resolver is used as the position feedback means.