JPH0580683B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a drive device using a joystick, and is used in measuring machines such as projectors and three-dimensional measuring machines.

(Background of the Invention) Measuring machines such as projectors and coordinate measuring machines use sensors such as workpiece mounting tables (used in projectors, for example) and sensing objects such as touch probe signals (used in coordinate measuring machines, for example). 2. Description of the Related Art A device is known in which a moving member is automatically fed by a drive command from a joystick. That is, by tilting the operating lever of the joystick, an X-direction drive command and a Y-direction drive command that depend on the tilt angle and direction are obtained, thereby obtaining the desired moving direction and speed. The mounting table and sensing object could be moved to the target position at any speed and direction.

However, with conventional drive devices, a speed that continuously changes in response to the tilt angle of the joystick is given, so when the tilt angle varies due to hand shake, etc., the speed of the moving member varies as a result. This made it extremely difficult to maintain a constant speed. As a result, vibrations occur in the workpiece mounting table, the touch probe, and other detecting bodies, resulting in poor reproducibility of measurement results.

(Objective of the Invention) The present invention solves these drawbacks, and provides a drive device using a joystick that eliminates speed changes of moving members due to hand shake when operating the joystick operating lever, and improves reproducibility in measurements. The purpose is to provide.

(Summary of the Invention) The present invention provides a signal output that outputs a signal corresponding to the inclination angle of the operating lever in a drive device that drives a moving member at a speed corresponding to the inclination angle by inclining the operating lever of the joystick. means, inputting a signal from the means, quantizing the tilt angle range of the operating lever, giving a constant speed for each quantization range, and setting a speed region having hysteresis between each quantization range. a control means for outputting a command signal; a drive means for driving the moving member according to a signal from the control means;
This drive device is characterized in that it eliminates the adverse effects on the speed of change in the tilt angle of the operating lever caused by hand shake or the like. Note that in this specification, quantization includes not only dividing the lever inclination angle range uniformly (every certain range) but also non-uniformly dividing it.

(Embodiment) FIG. 1 is a block diagram of a first embodiment of the present invention.

The X-direction joystick 1, the Y-direction joystick 2, and the Z-direction joystick 3 each have an operating lever, and this operating lever has a neutral point erected by the force of a spring as its origin, and within a vertical plane containing the operating lever, It is supported by a shaft so that it can be tilted approximately 60 degrees in positive and negative directions, and its rotating shaft is connected to a potentiometer, etc. After the potentiometer obtains a signal corresponding to the tilt angle of the operating lever, it is converted into a digital signal. I'm starting to do that. In this way, the _drive commands _V〓
V〓 _Z is input to the microcomputer 4. The microcomputer 4 executes the respective joysticks 1 and 1 based on the flowchart shown in FIG.
_{Convert the drive commands V〓 _} 6. Input to Z direction driver circuit 7. Each driver circuit 5, 6, 7 has a corresponding motor 8, 9, 10
to drive. Therefore, the moving member 11 is driven three-dimensionally.

Next, the operation of the microcomputer 4 will be explained based on the flowchart of FIG. 2 and the operation diagram of FIG. 3. The microcomputer 4 first inputs the command signal _V〓X for the X-direction joystick 1, and it is determined whether the command value _V〓X is within the hysteresis range (step 20). That is, for example _, in Fig _{. 3} , if the command value _V〓
is output as Also, for example, if the command value V〓 ₃ is
If V〓 changes to ₄ , this is within the hysteresis range, so the process goes to step 22, where the higher speed command voltage V 2 of the two speed command voltages V ₁ and V ₂ corresponding to V〓 ₄ is changed _. However, the current speed command voltage V ₁
Determine whether it is larger or smaller than. In the present example, since V ₁ <V ₂ , the process proceeds to step 23 and V ₁ continues to be output as the speed command voltage. _{Next ,} if _{the command value V〓} >V ₁ , the process passes through step 22 and enters step 24. In step 24, V ₁ is set instead of V ₂ ;
This becomes a new speed command voltage.

In other words, in step 20 it is determined whether the command value is within the hysteresis range or not based on the command value, and if it is not within the hysteresis range, in step 21 the voltage V _o determined by the command value is set as the current command speed voltage V _NOW , If it is within the hysteresis range, in step 22, the magnitude relationship between the higher voltage VH _o with the hysteresis range and the current speed command voltage V _NOW is determined, and V _NOW ≧
If VH _o , in step 23, the higher voltage VH _o with hysteresis is set to the current speed command voltage V _NOW.
If V _NOW < VH _o , in step 24, the lower voltage VL _o with hysteresis is set as the current speed command voltage V _NOW . The microcomputer 4 then sends a command signal for the Y-direction joystick 2.
Input V〓 _Y, perform the same processing as above, and when it is completed, command signal for Z direction joystick 3
Input V〓 _Z and perform the same processing as above.

As you can see in Figure 3, for example, from V〓 ₄ to V〓 ₅
As the tilt angle of the operating lever increases, the voltage
V ₁ changes to V ₂ near the middle. However, once the voltage V ₂ changes, the voltage V 2 will not change even if the tilt angle of the operating lever is changed around the change, so the speed command voltage V ₂ may change due to hand shake caused by operating the operating lever, _etc. It never changes. In other words, in a device without hysteresis, the operating lever tilt angle range in which the speed command voltage V _o does not change varies depending on the operating lever's inclination angle, but in the case of this example, the speed command voltage V _o does not change. The allowable angular range is always constant (when the quantization width is constant) regardless of the tilt angle of the operating lever. Of course, if the quantization width is not constant, the allowable angle range will not be constant. Therefore, the speed of the moving member driven by the speed command voltage _V2 does not change slightly.

Furthermore, in the above embodiment, one joist that corresponds to each axis is used as a joystick that drives the moving member three-dimensionally.
Although three dimensional sticks were used independently, it is also possible to control the X and Y directions by using a joystick that has an operating member that can be tilted two-dimensionally. Needless to say, the same effect can be achieved even if the knob is made rotatable and the Z direction can be controlled by the rotation angle.

Furthermore, it goes without saying that the microcomputer of the above embodiment can be realized using hardware having the same functions.

(Effects of the Invention) As described above, according to the present invention, the speed of the moving member can be selected with hysteresis even if there are variations due to hand shake during tilting of the joystick operating lever. Since the speed can be kept constant and causes of variation such as vibration caused by speed changes can be eliminated, it is possible to obtain a drive device that can improve reproducibility in measurement.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG.
This figure is a flowchart of the microcomputer used in the embodiment shown in FIG. 1, and FIG. 3 is an operation explanatory diagram showing the relationship between the speed command voltage (V _o ) and the tilt angle (V〓) of the operating lever. (Explanation of symbols of main parts), 1...X direction joystick, 2...Y direction joystick,
3... Z-direction joystick, 4... Microcomputer, 5, 6, 7... Driver circuit,
8, 9, 10...Motor, 11...Moving member.

Claims (1)

[Scope of Claims] 1. A drive device that drives a moving member at a speed corresponding to the tilt angle by tilting a control lever of a joystick, comprising: a signal output means for outputting a signal corresponding to the tilt angle of the control lever; A command signal that inputs a signal from the means, quantizes the tilt angle range of the operating lever, gives a constant speed for each quantization range, and sets a speed region having hysteresis between each quantization range. A drive device comprising: a control means for outputting a signal; and a drive means for driving a moving member based on a signal from the control means.