KR C2 / KR C3

(1)

SOFTWARE

KR C2 / KR C3

Start--up

KUKA System Software (KSS) Release 5.2

Issued: 26 Sep 2003 Version: 00

(2)

This documentation or excerpts therefrom may not be reproduced or disclosed to third parties without the express permission of the publishers.

Other functions not described in this documentation may be operable in the controller. The user has no claim to these functions, however, in the case of a replacement or service work.

We have checked the content of this documentation for conformity with the hardware and software described. Nevertheless, discrepancies cannot be precluded, for which reason we are not able to guarantee total conformity. The information in this documentation is checked on a regular basis, however, and necessary corrections will be incorporated in subsequent editions.

Subject to technical alterations without an effect on the function.

PD Interleaf

(3)

1 Robot mastering/unmastering . . . . 5

1.1 General. . . 5

1.2 Mastering with the dial gauge . . . 7

1.3 Mastering with the EMT. . . 9

1.3.1 Brief description of the functions . . . 9

1.3.2 Application examples . . . 10

1.3.3 Preparation for EMT mastering . . . 11

1.3.4 Standard. . . 12

1.3.4.1 Set mastering . . . 12

1.3.4.2 Check mastering. . . 13

1.3.5 With load correction . . . 15

1.3.5.1 First mastering . . . 15

1.3.5.2 Teach offset . . . 16

1.3.5.3 Master load . . . 18

1.4 Save mastering data . . . 21

1.5 Mastering the KR 3. . . 22

1.5.1 Robot mastering . . . 23

1.5.2 Commutation . . . 23

1.5.3 Alter factory mastering. . . 24

1.6 Reference point mastering . . . 25

1.7 Unmastering an axis . . . 26

1.8 Mastering of master/slave drives . . . 27

2 Calibration . . . . 29

2.1 Fundamentals . . . 29

2.1.1 Prerequisites . . . 29

2.1.2 Introduction . . . 30

2.2 Tool calibration . . . 33

2.2.1 X Y Z -- 4--Point. . . 34

2.2.2 X Y Z -- Reference . . . 37

2.2.3 A B C -- 2--Point . . . 41

2.2.4 A B C -- World . . . 45

2.2.4.1 The “A B C -- World (5D)” method . . . 45

2.2.4.2 The “A B C -- World (6D)” method . . . 47

2.2.5 Numeric Input . . . 49

2.2.6 Payload data . . . 52

2.3 Base . . . 55

2.3.1 3--Point . . . 55

2.3.2 Indirect . . . 59

2.4 Fixed tool . . . 64

2.4.1 Workpiece . . . 64

2.4.1.1 Direct measuring. . . 64

2.4.1.2 Indirect measuring . . . 68

2.4.2 Tool . . . 73

(4)

2.4.3 Offset external kinematic. . . 77

2.5 Supplementary load data. . . 84

2.6 External kinematic . . . 85

2.7 Measurement Points . . . 86

2.8 Tolerances . . . 87

2.9 Error treatment . . . 88

3 Calibration -- External kinematics . . . . 91

3.1 Root point. . . 92

3.2 Root point (numeric). . . 95

3.3 Offset . . . 97

3.4 Offset (numeric) . . . 100

3.5 Offset external kinematic. . . 102

4 Robot Data . . . . 103

(5)

1 Robot mastering/unmastering

1 Robot mastering/unmastering

1.1 General

When mastering the robot, the axes are moved into a defined mechanical position, the so--called mechanical zero position. This mechanical zero position represents an assignment to the axis drive angle and is defined by a reference notch or mark.

Once the robot is in this mechanical zero position, the increment counter for each axis is set to the value corresponding to the axis angle (generally 0 increments for 0 degrees). In order to move the robot exactly to the mechanical zero position, a dial gauge or electronic measuring tool (EMT) is used.

The robot must always be mastered under the same temperature conditions and with the same load in order to avoid inaccuracies arising through thermal expansion. This means that mastering must be carried out with the robot always cold or always at operating temperature.

Vernier on axis 5 Gauge cartridge on axis 2

Depending on the size of the robot, the axes feature either a vernier or a gauge cartridge for receiving a dial gauge or an electronic measuring tool (EMT).

1 Reference notch 2 Electronic measuring

tool or dial gauge 3 Gauge pin 4 Gauge cartridge 2

3

4

1

Cross--section of a gauge cartridge To locate the mechanical zero position of a robot axis precisely, it must first be aligned to its pre--mastering position. The protective cap of the gauge cartridge is then removed and a dial gauge or an EMT is fitted to it. The EMT is connected via a cable to connection “X32” on the robot junction box.

When, on moving over the reference notch, the gauge pin reaches its lowest point, the mechanical zero position is reached. The electronic measuring tool sends an electronic signal to the controller. The corresponding axis is mastered.

If using a dial gauge, the zero position can be recognized by the abrupt reversal of the pointer.

(6)

The pre--mastering position makes it easier to move to the mechanical zero position. The pre--mastering position is indicated externally by a scribed line or “frontsight/rearsight”

markers and is located just before the zero position. The robot must be brought into this position before the actual mastering procedure.

Scratch mark or

“frontsight/rearsight” marker

Axis motion direction

Pre--mastering position EMT or

dial gauge

Axis motion direction

EMT or dial gauge

Mechanical zero position An axis may only be moved to its mechanical zero position from “+” to “--”. If the axis has to be moved from “--” to “+”, it must first be moved past the pre--mastering position mark in order to move it subsequently back to the mark in the right direction. This is of vital importance, in order to eliminate the effect of gear backlash.

The robot may have to be remastered for a number of different reasons:

The robot has to be mastered... Mastering is canceled...

... after repairs

(e.g. replacement of a drive motor or RDC) ... automatically on booting the system¹⁾

... when the robot has been moved without the

controller (e.g. with hand crank) ... automatically on booting the system¹⁾

... after an impact with a mechanical end stop at

more than jog velocity (20 cm/s) ... manually by the operator ... after a collision between the tool or robot and

the workpiece ... manually by the operator

1)If discrepancies are detected between the resolver data saved when shutting down the controller and the current position, all mastering data are deleted for safety reasons.

The robot can be unmastered... Mastering is canceled...

... if the mastering values saved for the individual

axes are to be specifically deleted ... manually by the operator You can only master the axes if there is no EMERGENCY STOP situation and the drives are switched on. The EMERGENCY STOP circuits of the periphery must be wired up, if applicable.

When mastering the wrist axes, consideration needs to be given to the position of any external energy supply system as axes 4 and 6 are defined as infinitely rotating before the mastering process is carried out.

(7)

1 Robot mastering/unmastering (continued)

1.2 Mastering with the dial gauge

Bring all axes to the pre--mastering position.

The pre--mastering position depends on the robot type.

Pre--mastering position of axis 3

n

!

An axis may only be moved to its mechanical zero position from “+” to “--”. If the axis has to be moved from “--” to “+”, it must first be moved past the pre--mastering position mark in order to move it subsequently back to the mark in the right direction. This is of vital importance, in order to eliminate the effect of gear backlash.

Remove the protective cap of the gauge cartridge and fit the dial gauge.

This function is only available in the operating mode Test (T1/T2). If, when selecting this function, a different operating mode is set, a corresponding error message is generated.

Setup Measure

Master UnMaster Software Update Service Robot Data

DialEMT

Save current data

A status window opens, in which the axes to be mastered are displayed.

(8)

The axes are displayed in the order in which they are to be mastered. The axis that is to be mastered next is indicated by a color background.

Axes that are already mastered are no longer listed and, if remastering is desired, must first be unmastered.

If axis 1 has been mastered, it may be moved for the purposes of mastering the remaining axes. Axes 2...6, on the other hand, may not be moved until all axes have been mastered.

The mastering operation will be aborted if you try to master an axis with a higher number than this one first. Mastering must always be carried out on the axis with the lowest number.

Before carrying out mastering, please use jog override to reduce the jog velocity to 1%. Move the robot axis that is to be mastered across the pre--mastering position marker, in the negative axis direction, while watching the pointer of the dial gauge. At the lowest position of the reference notch, recognizable by the abrupt change in direction of the pointer, set the dial gauge to 0.

Then move the axis back to the pre--mastering position. Move the axis that is to be mastered in the negative axis direction again. Stop when the pointer of the dial gauge is about 5--10 scale divisions before the zero position. In order to increase the accuracy of mastering, move the robot forward more carefully now, in predefined increments (incremental jogging).

In this way, move the axis in the negative axis direction until the zero position of the dial gauge is reached.

If you overshoot this point, you must go back and move to the reference notch from the pre--mastering position again.

The current axis position, highlighted by the colored selection bar, is saved as the mechanical zero position for the axis by pressing the softkey “Master”.

The axis that has been mastered is removed from the window.

Before mastering the next axis or ending the complete mastering procedure, switch back to the normal jog mode.

Remember to screw the protective cap back onto the gauge cartridge once an axis has been mastered. Do not allow foreign bodies to get inside as they would damage this sensitive measuring device and necessitate expensive repairs.

Master

(9)

1.3 Mastering with the EMT

A number of different functions are available for mastering with the EMT. These are grouped together under two main points: “Standard” and “With load correction”. The difference here is that using the option “With load correction” it is possible to master the robot as if the tool had been removed, but actually leave the tool mounted on the robot. This is done by correct- ing the weight of the tool “arithmetically”. “Standard” mastering is used if the robot is always mastered with the same tool or always mastered with no tool.

1.3.1 Brief description of the functions Standard:

G Set mastering

The robot is mastered in the mechanical zero position with or without a payload.

G Check mastering

Here it is possible to check the mastering, i.e. if you are not sure whether or not the currently valid mastering is correct, the difference from the “Set mastering” values can be calculated. Bear in mind that the robot must be fitted with the same load as when

“Set mastering” was carried out.

With load correction:

G First mastering

The robot is mastered in the mechanical zero position without a payload. The absolute value of the incremental encoder is saved for each axis. First mastering serves as the basis for the other functions listed below.

G Teach offset

Using this function, the robot is mastered with a load (tool). The encoder value for the offset from the first mastering is determined for this load and saved.

G Master load with offset

This function is used to check the mastering of a tool mounted on the robot, for which an “offset” has been learnt. The saved “offset” is used to recalculate the mastering value

“without load” and calculate and display the difference between this value and the current mastering (up to this point no values have yet been saved).

Following this check function, the operator is asked whether the existing mastering state is to be retained or whether the newly calculated mastering values are valid and should be saved. This menu item thus allows the first mastering to be restored even after a collision or following the replacement of a motor.

G Master load without offset

The robot can be mastered with any load (including a tool whose weight has not been learnt). i.e. no allowance is made for an offset. Instead, only the absolute encoder value determined in first mastering is used to recalculate the first mastering. A precondition for this function is that nothing has been mechanically displaced (e.g. collision, replacement of motor, parts, etc.) since the first mastering.

(10)

*)1 Only possible if the first mastery is still valid (i.e. no change to the drive train e.g. replacement of a motor or parts, or following a collision, etc.)

Set mastering First mastering

Teach offset

Check mastering Master load with

offset Master load

without offset *)1 CommissioningMastering Loss/Check

Mastering with EMT

For reasons of accuracy, the wrist axes should remain, if possible, in their mechanical zero position during the EMT mastering function.

1.3.2 Application examples

Example 1 Mastering without consideration of the load

You have carried out “Set mastering” and then taught a program on which you have been working for some time. Now you are not sure if this mastering is correct. You can now check this using the “Check mastering” function. A precondition for this is that the robot is fitted with the same load as when “Set mastering” was carried out. Once the check has been carried out, the difference from the currently valid mastering is displayed and you have the option of overwriting the old mastering with the one just carried out or retaining the existing mastering values as valid. If you decide to opt for the new mastering, you must be aware that, in the event of a significant mastering difference, the program you have taught is no longer correct.

Example 2 Mastering with consideration of the load

Despite having a load mounted on the robot flange, you wish to master the robot, as if no load were present. In this way you can always precisely master a robot which works, for example, with different loads (gripper, tool changer, etc.), irrespective of the current load and without having to remove the load. There are two ways of doing this:

1. Taking the tool load into account by learning the weight difference:

In this case, the mastering difference caused by a load is explicitly measured and saved in advance for the load in question. Using this value, the computer can take this difference into consideration in the event of subsequent mastering with a load. When using this method, the following must be carried out:

First mastering must be carried out once without a load. The weight of each tool must then be learnt using the function “Teach offset”. Provided that this has been done, you can subsequently carry out “Master load -- With offset” to restore the old first mastering.

(11)

2. Taking the tool load into account by saving the encoder value:

When mastering without a load (first mastering), the path calibration system value (absolute encoder value) is read and saved for each axis. In the event of subsequent mastery with a load, the difference is determined and corrected by comparing the current encoder value with the saved value. The precondition for this method is that the robot has not undergone any mechanical changes since the first mastering. When using this method, the following must be carried out:

First mastering must be carried out once without a load. Provided that this has been done, you can subsequently carry out “Master load -- Without offset” to restore the old first mastering.

1.3.3 Preparation for EMT mastering

When mastering with the EMT, the axis that is to be mastered is moved at a preset velocity from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the controller automatically stops the robot motion and saves this point.

If during the mastering operation a specified distance is overshot, the program is aborted and an error message is displayed. The most common reason for this happening is that the axis was positioned to the pre--mastering position with inadequate accuracy.

Bring all the axes to be mastered to the pre--mastering position.

Pre--mastering position of axis 3

n

!

When mastering with the EMT, an axis is always moved to the mechanical zero posi- tion from “+” to “--”. If the axis has to be moved from “--” to “+”, it must first be moved past the pre--mastering position mark in order to be able to move it subsequently back to the mark in the right direction. This is done in order to eliminate the effect of gear backlash.

Remove the protective cap of the gauge cartridge and fit the measuring tool.

(12)

Connect the EMT to connection X32 on the robot junction box using the cable supplied with the EMT set.

Connection X32

The connecting cable for the EMT is connected here.

Junction box on the rotating column of the robot

If you wish to remove the connecting cable from the EMT or X32, the connector on the cable must be released. Otherwise the cable could be torn out or the EMT damaged.

The menu structure for mastering with the EMT is organized as follows:

Setup Measure

Master UnMaster Software Update Service

Robot Data Standard

With load corr.

Set mastering Check mastering

First mastering Teach offset

Master load With offset Without offset DialEMT

Save current data

1.3.4 Standard

In the “Standard” menu, mastering with/without a load can be set and checked. This mastering function is recommended if the robot is always mastered with the same tool (load) or always mastered with no tool (load).

1.3.4.1 Set mastering

Setup Measure

Dial

EMTSave current data

Standard

With load corr: Set mastering Check mastering

This function is only available in the operating mode Test (T1). If, when selecting this function, a different operating mode is set, a corresponding error message is generated.

(13)

The axes are displayed in the order in which they are to be mastered. The axis that is to be mastered next is indicated by a color background. If all axes have been mastered, the text “No axes to master” appears in the window.

Axes that are already mastered are no longer listed and, if remastering is desired, must first be unmastered. Furthermore, it is also possible to initiate a new mastering procedure via the menu item “Check mastering”.

The highlighted axis is selected for mastering by pressing the softkey

“Master”. The text “Start key required” appears in the message window.

Press the enabling switch on the back of the KCP, then the “Program start forwards” key, and keep both held down. The robot axis previously selected is now moved from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped. The determined values are saved and the mastered axis removed from the window.

1.3.4.2 Check mastering

This function allows the old robot mastering values to be checked. The robot is mastered in the same way as for “Set mastering”.

Setup Measure

Dial

EMTSave current data Standard

With load correction Set mastering Check mastering Master

(14)

A status window is opened, in which the axes to be checked are listed.

If, for example, axis 2 has not been mastered, or has been unmastered, it is not possible to check the mastering of an axis with a higher number. Axis 2 must first be mastered using

“Set mastering” or “Check mastering” in order to be able to check, for example, axis 3.

The axis for which the mastering is to be checked is selected by pressing the softkey “Check”. The text “Start key required” appears in the message window.

Press one of the enabling switches and then the “Program start forwards” key.

Keep both keys held down. The robot axis previously selected is now moved from

“+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped.

The values are calculated and a status window is opened, in which the difference from the old mastering is displayed in increments and degrees.

Pressing the softkey “Save” saves the mastering values and enables the selection of the next axis.

You must be aware, when accepting the new mastering, that difficulties may arise during execution of the program, depending on the difference in increments. For this reason, it is necessary to reteach all programs.

Acceptance of the new mastering also offsets the mastering of all subsequent mechanically coupled axes (the wrist axes are generally mechanically coupled). In this case, it is absolutely necessary to check the mastering of these axes and, if the deviation is too great, set the mastering as well.

Check

Save

(15)

1.3.5 With load correction

Here you can carry out first mastering and load mastering and teach offsets for various tools and loads. A precondition for “Load mastering” and “Teach offset” is first mastering.

1.3.5.1 First mastering Please note:

The first mastering of the robot must always be carried out without a payload or a supplementary load.

This function is only available in the operating mode Test (T1). If, when selecting this function, a different operating mode is set, a corresponding error message is generated.

Setup Measure

DialEMT

Save current data

Standard With load corr.

First mastering Teach offset Master load

A status window opens, in which all the axes (both mastered and unmastered) for which an offset has been taught are available for selection. Select here the axis to be mastered.

The axes are displayed in the order in which they are to be mastered. The axis that is to be mastered next is indicated by a color background. If all axes have been mastered, the text “No axes to master” appears in the window.

Axes that are already mastered are no longer listed and, if remastering is desired, must first be unmastered. It is also possible to initiate a new mastering procedure via the menu item “Check mastering” in the “Standard” menu.

The axis (highlighted in color) that is to be mastered is selected by pressing the softkey “Master”. The text “Start key required” appears in the message window.

Press the enabling switch on the back of the KCP, then the “Program start forwards” key, and keep both held down. The robot axis previously selected is now moved from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped.

Master

(16)

The determined values are saved and the mastered axis removed from the window.

1.3.5.2 Teach offset

If, after first mastering, the robot is fitted with a heavy tool or workpiece, the increased load gives rise to deviations (offset) from the first mastering. Should it be necessary to repeat mastering (e.g. due to a collision or the replacement of a motor), this offset can be used to recalculate the first mastering. Where different tools or payloads are used, in order to be able to recalculate the mastering without having to change the tool, the offset must be taught for all tools and payloads.

For this purpose, the robot is fitted, after first mastering, with the corresponding tool or workpiece and, if necessary, a supplementary load. In the subsequent mastering procedure, the robot “learns” the mastering difference caused by the load (offset).

Setup Measure

DialEMT

Save current data Standard With load corr.

First mastering Teach offset Master load

...

Use the status key to select the tool number.

The input window for selecting a tool is opened.

Press the softkey “Tool OK” in order to enter data for this tool.

A status window opens, in which all axes are available for selection for which the load of the selected tool has not yet been taught.

Select the axis to be taught.

The axis (highlighted in color) for which an offset is to be taught is selected by pressing the softkey “Teach”. The text “Start key required” appears in the message window.

Tool OK

Learn

(17)

Press the enabling switch on the back of the KCP, then the “Program start forwards” key, and keep both held down. The robot axis previously selected is now moved from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped.

When the data for the tool or workpiece fitted to the robot flange have been successfully determined, the status window shown here is opened, displaying in increments and degrees the offset from the mastering without load for this axis.

Pressing the softkey “OK” saves the mastering values and enables the selection of the next axis. The axis whose weight has just been learnt is removed from the status window. If the offsets have been taught for all axes, the message “No offset to teach” appears in the window.

If you wish to delete an offset, press the softkey “Delete”. A window opens, in which the axes to be deleted are displayed. The tool number previously selected is confirmed.

Use the arrow keys to select the axis for which the offset is to be deleted and press the softkey

“Delete”. If there are no more offsets to be deleted, the message “No offset to delete” appears in the window.

The values for learnt tools remain valid even after the replacement of a motor or a collision, as they contain only the difference from the first mastering.

If, at the beginning of the learning process, no first mastering has yet been carried out, this must be done first. For this reason the program automatically opens the necessary dialog window. Please pay particular attention to the contents of the text in the status window!

OK

Delete

(18)

1.3.5.3 Master load

With the load mastering function, mastering is carried out with a load. A distinction is made here between “With offset” and “Without offset”.

In order to carry out Load mastering, it must be ensured that robot axes A 4 and A 6 have not been rotated from the positions they occupied during first mastering.

With offset

This function makes it possible to check and, if necessary, restore the robot’s old mastering values without having to remove the tool. The robot is mastered with the tool (known offset).

The mastering data for the state “Without load” (first mastering) are recalculated using the offset and overwritten after confirmation by the operator. This can be necessary, for example, if a motor has been replaced or a collision has occurred.

A check is also possible in the event of loss of mastering; in this case the data are marked as invalid, but these old values are nonetheless still available.

Setup Measure

DialEMT

Save current data

Standard With load corr.

Master load With offset Without offset

The input window for selecting a tool is opened.

Use the status key to select the tool number.

...

Press the softkey “Tool OK” in order to enter data for this tool.

If no offset has yet been taught for the tool, an error message is now generated.

A status window opens, in which all the axes (both mastered and unmastered) for which an offset has been taught are available for selection. Select here the axis to be mastered.

Tool OK

(19)

If, for example, axis 2 has not been mastered, or has been unmastered, it is not possible to check the mastering of an axis with a higher number. Axis 2 must first be mastered using

“Set mastering” or “Check mastering” in order to be able to check, for example, axis 3.

The axis highlighted by the colored selection bar is selected by pressing the softkey “Check”. The text “Start key required” appears in the message window.

Press the enabling switch on the back of the KCP, then the “Program start forwards” key, and keep both held down. The robot axis previously selected is now moved from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped.

When the mastering data for the tool or workpiece fitted to the robot flange have been successfully determined, a status window is opened, displaying the difference from the old mastering in increments and degrees.

No new mastering values have yet been set, however. This is done once the data have been saved.

Pressing “Save” saves the new mastering values and enables the selection of the next axis. If you do not save the new data, the old mastering state is retained.

You must be aware, when accepting the new mastering, that difficulties may arise during execution of the program, depending on the difference in increments. For this reason, it is necessary to reteach all programs.

Acceptance of the new mastering also offsets the mastering of all subsequent mechanically coupled axes (the wrist axes are generally mechanically coupled). In this case, it is absolutely necessary to check the mastering of these axes and, if the deviation is too great, set the mastering as well.

Without offset

This function makes it possible to restore mastering data that have been lost. The robot can be mastered with any tool, for which the offset does not need to have been “taught” before- hand. Using the data determined in first mastering and the current values, the difference is calculated and the mastering corrected accordingly.

The robot must not have been changed mechanically, since first mastering, in the drive train between the drive motor with resolver and the gear system of the axis concerned (e.g. following replacement of a motor or a collision). Otherwise first mastering must be carried out again.

Check

Save

(20)

Unlike the menu item “Teach offset” (which only measures the difference from first mastering) “Restore mastering” uses exclusively the absolute encoder value determined during first mastering to recalculate the first mastering.

First mastering must have been carried out before mastering can be restored in this way.

Setup Measure

DialEMT

Save current data Standard With load corr.

Master load With offset Without offset

A status window opens, initially displaying just one message.

Please read the message and confirm it by pressing the softkey “OK” in order to continue.

The axes are displayed in the order in which they are to be mastered. The axis that is to be mastered next is indicated by a color background.

The axis to be mastered, highlighted by the colored selection bar, is selected by pressing the softkey “OK”. The text “Start key required” appears in the message window.

OK

(21)

Press the enabling switch on the back of the KCP, then the “Program start forwards” key, and keep both held down. The robot axis previously selected is now moved from “+” to “--” under program control. When the EMT detects the bottom of the reference notch, the calibration program is stopped. The determined values are saved and the mastered axis removed from the window.

1.4 Save mastering data

To prevent loss of mastering, it is possible to save the mastering data. Loss of mastering can occur, for example, in the event of a defective battery preventing the system from being shut down correctly (option “Battery monitoring”).

Setup Measure

DialEMT

Save current data

Once the mastering data have been saved a corresponding message is generated.

C... Time No. Source Message 11:12:25 1008

11:13:32 40 11:20:19 2960

Controller booted PowerOn finished.

Current mastering data is saved.

HMI

(22)

1.5 Mastering the KR 3

On the robot type “KR 3”, mastering is carried out using the verniers only; these are installed on each axis.

Vernier on the KR 3

The mastering procedure and mastering menu are completely different from those of the KR C1 and KR C2 versions. There is a total of three different commands available:

Command Function

Robot mastering Normal mastering

Commutation Motor – encoder synchronization

SetupMasterSetRobotPos First mastering

First of all, make sure that the operating mode “T1” and the option “Jog” are set.

This menu items “Commutation” and “Set robot position” are not available in the user group

“User”.

(23)

1.5.1 Robot mastering

This command can be used to master the robot, provided that a first mastering (“Alter factory mastering”) has already been carried out.

Setup

Robot mastering Commutation Alter factory mastering Measure

This causes the corresponding status window to be opened, in which the axes still to be mastered are displayed.

Then move the desired axis into the mastering position by bringing the respective vernier marks into alignment.

Then press the softkey “Master”. The entry for the corresponding axis is then removed from the status window.

1.5.2 Commutation

Commutation is used to synchronize the motor and the encoder. This function is required in the event of an encoder or motor exchange.

This function may only be carried out by our Service department or by personnel trained at KUKA Roboter GmbH.

Setup

This causes the corresponding status window to be opened, in which the axes to be commutated are displayed.

Master

(24)

This causes the corresponding status window to be opened, in which the axes to be commutated are displayed.

Then move the desired axes to a position which is as gravity--neutral as possible, and press the Start key.

A position which is as gravity--neutral as possible is necessary because the brake of the axis in question will be released briefly. An unfavorable position may lead to unintended axis motion during this procedure.

Then press the softkey “Master”. The brake of the axis in question is released briefly, the synchronization is carried out and then the brake is applied again.

The entry for the corresponding axis is not removed from the list; the procedure can be repeated at any time.

1.5.3 Alter factory mastering

This command is used for first mastering of the KR 3. Since KUKA Roboter GmbH generally ships all robots with the first mastering already performed, this step is normally not necessary. It must be carried out, however, if an encoder or motor is exchanged.

Setup

In order to carry out first mastering, the axis in question must first be unmastered; then execute the function “Commutation”.

Master

(25)

Move the axis to be mastered into the mastering position by bringing the vernier into alignment. Use a spirit level to check the exact position.

Then press the softkey “Master”. The entry for the corresponding axis is then removed from the status window.

1.6 Reference point mastering

If a robot axis has an absolute encoder, reference point mastering is possible for this axis.

The following mastering types are permissible here:

Setup Measure

Master UnMaster Software Update Service

Robot data Standard

With load corr.

Set mastering Check mastering First mastering Teach offset

Master load With offset Without offset DialEMT

Save current data

If at least one axis with an absolute encoder is unmastered, an additional status window for reference point mastering is displayed.

Displays the last value saved

Availability

The following options are offered in the softkey bar:

The two softkeys “Drive +” and “Drive --” are used to select the required master/slave drive.

The data saved on the DSE are used for mastering.

The mastering file most recently saved to the hard drive is used.

The robot is remastered using the dial gauge or EMT. The relevant procedures are described in the corresponding sections in this chapter.

Reference point mastering is terminated using the softkey “Close”.

Master

Drive + Drive --

DSE--Value

HD--Value

Master

Close

(26)

1.7 Unmastering an axis

With the aid of this function, individual axes can be specifically unmastered.

Setup Measure

A status window is then opened, in which the mastered axes are displayed. If all axes have already been unmastered, the text “No axes to unmaster” appears in the window.

The mastering data for the axis highlighted in color are deleted by pressing the softkey “UnMaster”.

On account of the mechanical coupling of the robot wrist axes, the data for axes 5 and 6 will also be deleted when axis 4 is unmastered, and similarly the data for axis 6 when axis 5 is unmastered.

The robot axes do not move during unmastering.

UnMaster

(27)

1.8 Mastering of master/slave drives

If the robot system contains additional position--controlled master/slave drives, they must be mastered prior to use.

This function is only available if the appropriate master/slave drives are present and the necessary entries have been made in the machine data.

Torque--controlled slave drives do not require mastering, and are not shown in the status window.

Setup

DialEMT Measure

EMT mastering of the master/slave drives is not possible.

The status line of the status window shows the robot axis currently active and the drive which is selected.

The status window for mastering is then opened.

The axes are displayed in the order in which they are to be mastered. The axis that is to be mastered is indicated by a color background.

The status keys “Drive +” and “Drive --” can be used to select a drive, which can then be jogged using the jog key of the corresponding axis. The possibilities here are:

G All: The selected axis and the master and slave drives are jogged together

G Master: Only the master drive is jogged

G Drive 1 ... 5: Only the corresponding slave drive is jogged

-- +

Here the status line in the status window indicates that when the “+/--” jog key of axis 1 is pressed, only slave drive no. 2 will be jogged.

Drive + Drive --

(28)

If all axes/drives have been mastered, the text “No axes to master” appears in the window.

Axes that are already mastered are no longer listed and, if remastering is desired, must first be unmastered. Furthermore, it is also possible to initiate a new mastering procedure via the menu item “Check mastering”.

The selected axis and the corresponding master and slave drives are mastered by pressing the softkey “Master”.

Master

(29)

2 Calibration

2 Calibration

2.1 Fundamentals

With the aid of the predefined calibration programs, you have a means of easily defining the dimensions of an

G unknown tool or G unknown workpiece

using several different procedures.

Tool center point (TCP) Workpiece reference point Robot guides the

Tool

X Y Z -- 4--Point Position

X Y Z -- Reference 3--Point

Position and orientation A B C -- World

Orientation

A B C -- 2--Point

orientation

Indirect

Robot guides the

Workpiece Position and Tool

orientation Position and Workpiece

orientation

The data for up to 16 tools or workpieces can be stored. These data are then called by number in the application program and enable a tool change to be easily programmed.

For reasons of safety, the calibration programs can only be executed in “T1” or “T2”

mode.

2.1.1 Prerequisites

Using the calibration functions requires adequate knowledge of operating the robot system.

The following preconditions must also be met:

G the correct machine data are loaded;

G all axes must be correctly mastered;

G no program may be selected;

G mode “T1” or “T2” is selected.

(30)

2.1.2 Introduction

The position of the flange center point is defined by its distance from the origin of the world coordinate system¹⁾(dotted line). This distance is specified in its X, Y and Z components (dashed lines).

X Y

Z X

Y Z

The origin of the world coordinate system¹⁾is located here.

The origin of the robot flange coordinate system is located here.

Z

1)In the basic setting, the world and robot coordinate systems coincide.

The orientation of the robot flange coordinate system, whose origin lies at the flange centerpoint, is defined by its rotational offset (Z--Y--X Euler angles) from the world coordinate system¹⁾.

X

Y Z

X

Y Z

Rotation about the Z axis

X

Y Z

X

Y Z

1.

When rotating a coordinate system, a defined sequence must be observed in order to achieve reproducible re- sults.

Angle A

X Y

Z

Rotation about the Y axis

2.

Angle B

Rotation about the X axis

3.

Angle C

-- --

--

-- +

+

(31)

2 Calibration (continued)

The information representing a point in space by specification of the coordinates X, Y, Z and the rotation angles A, B, C is called a FRAME.

1)In the basic setting, the world and robot coordinate systems coincide.

To enable the position of the reference point of a tool or workpiece mounted on the robot flange to be calculated, its location and orientation in relation to the robot flange coordinate system must be known to the robot controller.

The origin of the robot flange coordinate system is located here. Its position and orientation are known to the controller.

This is the TCP (Tool Center Point).

X

Y Z

These data can be determined with the aid of an external measuring device. Having been recorded on a form, the data can be entered into the robot controller at any time. After a collision, however, these data are no longer valid and must be re--determined.

200

X Z

X Y

TCP (Tool center point)

(32)

Another possible method of determining the tool data consists in measuring the tool by means of the calibration systems and calculation functions of the robot.

For this purpose, the TCP of the tool or workpiece mounted on the robot flange is moved to a reference point from various directions. This reference point can be located at any point within the work envelope of the robot.

The position of the TCP is then calculated on the basis of these various positions and orientations of the robot flange.

To enable the tool or workpiece to be moved as quickly as possible without overloading the drive systems of the robot, the load data of the tool or workpiece must be taken into account.

10 kg

Loadmoved

Maximum acceleration / velocity

100 kg

For this purpose, the weight, center of gravity and mass moment of inertia of the tool or workpiece must be entered into the controller.

Any supplementary loads mounted on the robot must not be forgotten.

(33)

2.2 Tool calibration

This submenu is used for calibrating a tool mounted on the robot.

The submenu “Tool” contains the following subprograms:

Program Calibration by...

X Y Z -- 4--Point moving the robot to a fixed reference point

X Y Z -- Reference moving the robot with a known reference tool to a reference point

A B C -- 2--Point moving the robot to 2 points with orientation data A B C -- WORLD positioning perpendicular to the world coordinate system Numeric Input entering the tool data

Payload data entering the mass, center of mass, mass moment of inertia

Each of these calibration programs is assigned forms that guide you interactively through the program.

Methods for determining the position

These methods are used to determine the position of the TCP in relation to the origin of the robot flange coordinate system.

These methods include the calibration programs “XYZ -- 4 Point”, and “XYZ -- Reference”.

Methods for determining the orientation

These methods are used to determine the rotational offset (A, B and C according to the Z--Y--X Euler angles) of the tool coordinate system from the robot flange coordinate system.

These methods include “A B C -- 2--Point” and “A B C -- WORLD”.

Y

Axis 5

X

Z

X₀

Y₀ Z₀

45°

(34)

ABC -- 2--Point

This method is used if an exact orientation of the three tool axes is required for positioning and manipulation. It requires marked points to be available on the positive side of the XY plane and on the negative side of the X axis of the tool.

A B C -- World (5D)

This method is used if only the working direction of the tool is required for its positioning and manipulation (MIG/MAG welding, laser or waterjet cutting).

A B C -- World (6D)

This method is used if the orientation of all three tool axes is required for positioning and manipulation (for example: welding guns, grippers, adhesive nozzles).

Method for TOOL orientation

If a tool is known, its dimensions and angular positions are entered. This is done via the menu item “Numeric Input” (see Section 2.2.5).

2.2.1 X Y Z -- 4--Point

In the “4--Point” method, the TCP of the tool is moved to a reference point from four different directions (hence “4--Point” method).

The position of the TCP is then calculated on the basis of the various positions and orientations of the robot flange.

Procedure

Mount the tool to be calibrated onto the robot flange and establish a suitable reference point.

This can be the tip of the reference spike installed in the work envelope or also a distinctive corner of a workpiece or a fixture.

Setup Tool

Base Fixed tool

Supplementary load data External kinematic Measurement Points Tolerances Measure

X Y Z -- 4--Point X Y Z -- Reference A B C -- 2--Point A B C -- World Numeric Input Payload data

The dialog window for 4--point calibration is opened.

Use the status key and the +/-- key to select the desired tool number. Calibration data for a total of 16 different tools can be stored. The current dimensions or angles of the tool in question are displayed in the bottom part of the status window.

...

You can use the arrow keys to access the tool name input box and there enter a name for the tool.

Press the softkey “OK” in order to calibrate the selected tool. The next status window is then automatically opened.

OK

(35)

You are now prompted to align the tool to a reference point from different directions.

Either the axis jog keys or the Space Mouse can be used to do this. Now carry out the following steps in the order given:

G Set the desired tool orientation.

G Move the TCP to the reference point.

G When the TCP is located exactly on the reference point, save its position by pressing the softkey “OK”.

OK

If the selected points are too close together, an error message is generated.

You can now press the softkey “Repeat” to repeat the last calibration, or the softkey “Repeat All” to repeat all calibrations.

After the point has been accepted by the controller, you are prompted to align the TCP to the reference point from another direction. Repeat these steps until the reference point has been addressed from four directions and the point coordinates transferred.

P1

P2 P4

P3

Fixed point in

space

Z

_W

Z

_W

X

_T

Y

_T

Reduce the jog velocity in the vicinity of the reference object in order to avoid a collision.

For this purpose you can use raise or lower the jog velocity using the +/-- key of the

“Jog--OV” status key. Reducing the deflection of the Space Mouse also reduces the velocity.

Repeat

(36)

At the end of the calibration procedure, you will be offered the softkey “Save”. Save the tool data by pressing this softkey. This terminates the function.

Save

You are currently able to open the corresponding subprograms by means of the softkeys

“A B C -- 2--Point”, “A B C -- World” or “Load data”. It is also possible to view the calibrated points by pressing the softkey “Meas. Pt.”.

(37)

2.2.2 X Y Z -- Reference

In this method, the data of a tool to be calibrated are determined by means of comparison with a known tool by moving the TCP to a reference point.

This is done by moving a tool of known dimensions to a reference point from any direction.

Fixed point in space Known tool

The tool to be calibrated is then mounted on the robot flange.

This tool is then also moved to the reference point from any direction.

Fixed point in space Unknown tool

On the basis of the various positions and orientations of the robot flange and the known dimensions of the tool previously used, the robot controller can now calculate the dimensions of the tool that is to be calibrated.

Procedure

Mount a tool whose dimensions are known to the controller onto the robot flange and establish a suitable reference point.

This can be the tip of the reference spike installed in the work envelope or also a distinctive corner of a workpiece or a fixture.

Setup Tool

Base Fixed tool

The following dialog window is opened after this menu has been selected.

...

(38)

You can use the arrow keys to access the input box “Tool name” and there enter a name for the tool.

Press the softkey “OK” in order to edit the data for this tool. The dialog window for data entry is then opened.

Use the numeric keypad to enter the dimensions of the reference tool, i.e. the known tool, in the input boxes X, Y and Z.

You can move between the input boxes using the “¯” and “” arrow keys.

Example:

X, Y, Z Position of the TCP relative to the origin of the robot flange coordinate system (located at the center of the flange).

X

Y Z

X = +50 Y = 0 Z = 0

Flange adapter plate as reference tool

OK

(39)

In the example:

If the entries have been made correctly, confirm this by pressing the softkey

“OK”. The window prompting you to move to the reference point is opened.

The robot can be moved using either the jog keys or the Space Mouse. Now carry out the following steps in the order given:

G Set the desired tool orientation.

G Move the TCP to the reference point.

When the TCP is located exactly on the reference point, save its position by pressing the softkey “OK”.

Reduce the jog velocity in the vicinity of the reference point in order to avoid a collision.

To do so, repeatedly press the status key on the right of the display.

After the point has been accepted by the controller, you are prompted to align the tool that is to be calibrated to the reference point.

First move the tool away from the reference point. Then replace the known tool with the unknown tool and move to the reference point again.

OK

(40)

Fixed point in space Known tool

Unknown tool

To do so, repeatedly press the status key “Jog override”, on the right of the display.

Now confirm the position with the softkey “OK”. The X, Y and Z dimensions of the defined tool are displayed in the form that is then opened.

The data are saved and the calibration program is ended by pressing the softkey

“Save”.

--6.31 Save 19.36 --27.57

You are currently able to open the corresponding subprograms by means of the softkeys

“A B C -- 2--Point”, “A B C -- World” or “Load data”. It is also possible to view the calibrated points by pressing the softkey “Meas. Pt.”.

OK

(41)

2.2.3 A B C -- 2--Point

In this method, the orientation of the tool coordinate system is defined in two steps.

X Y

Z

Reference point

In the first step, the working direction of the tool is defined for the controller.

This is done by moving the TCP to a known reference point.

Y

X Z

Reference point

It is now necessary to move a point located opposite the TCP on the tool to the same reference point (in the reverse working direction).

The working direction of the tool is now defined.

Y

Z

X Reference point

The YZ plane can still rotate freely about the X axis (working direction) of the tool and is defined in the second step.

This is done by moving the tool so that the reference point is located with a positive Y value on the future XY plane of the tool.

(42)

Procedure

Mount the tool to be calibrated onto the robot flange and establish a suitable reference point.

This can be the tip of the reference spike installed in the work envelope or a distinctive corner of a workpiece or a fixture.

Setup Tool

BaseFixed tool

The following dialog window is opened after this menu has been selected.

...

If this definition procedure is called by means of the softkey “X Y Z -- Reference”, the form for entering the tool number will not be opened.

Press the softkey “OK” in order to edit the data for this tool. The dialog window for entering the TCP value is then opened.

Position the TCP (tool center point) to a reference point.

OK

For this purpose you can use raise or lower the jog velocity using the +/-- key of the “Jog--OV” status key. Reducing the deflection of the Space Mouse also reduces the velocity.

(43)

When the TCP is located exactly on the reference point, save this position by pressing the softkey “OK”. The status window then changes.

First move the tool away from the reference point.

OK

Here also, reduce the jog velocity in the vicinity of the reference object in order to avoid a collision.

To do so, press the status key “Jog--OV” again.

Y

X Z

Position a point located opposite the TCP in the reverse working direction to the reference point.

To do so, repeatedly press the status key shown here (on the right of the display).

When the TCP is located exactly on the reference point, save this position by pressing the softkey “OK”. The status window then changes again.

OK

(44)

Move the tool so that the reference point is located with a positive Y value on the future XY plane of the tool.

To do so, repeatedly press the jog override status key.

When the TCP is located exactly on the reference point, save this position by pressing the softkey “OK”.

If the error message Point too near to reference point is displayed, the distance to the previous point is too small. The form cannot be closed by pressing “Point Ok” until the distance has been increased.

Save

Save the tool data by pressing the softkey

“Save”. The function is then terminated.

At this point you can open the corresponding subprogram by means of the softkey “Load data”. More detailed information about this can be found in Section 2.2.6. It is also possible to view the three different measuring points (coordinates) by pressing the softkey “Meas.

Pt.”.

OK

(45)

2.2.4 A B C -- World

Setup Tool

Base Fixed tool

The approach is different depending on whether you are using the 5D or 6D method.

2.2.4.1 The “A B C -- World (5D)” method

In this method, the tool must be oriented parallel to the Z axis of the world coordinate system in the working direction. The Y and Z axes are oriented by the robot controller. The orientation of these axes is not readily foreseeable in this instance, but it is exactly the same in each calibration procedure.

X Z Y

X₀ Y₀

Z₀ Condition:

X parallel to Z₀

Procedure

Mount the tool to be calibrated onto the robot flange. Select the menu item “A B C -- World”.

The dialog window for selecting the tool number is then opened:

Select the tool number (1...16) which can be altered by means of the +/-- keys of the corresponding status keys. The current values for the selected tool are displayed in the bottom part of the status window.

...

Press the softkey “OK” in order to enter data for this tool.

OK

KR C2 / KR C3

SOFTWARE

KR C2 / KR C3

Start--up

KUKA System Software (KSS) Release 5.2

Issued: 26 Sep 2003 Version: 00

Contents

1 Robot mastering/unmastering . . . . 5

2 Calibration . . . . 29

3 Calibration -- External kinematics . . . . 91

4 Robot Data . . . . 103

1 Robot mastering/unmastering

1.1 General

1.2 Mastering with the dial gauge

n

!

1.3 Mastering with the EMT

Mastering with EMT

n

!

...

...

1.4 Save mastering data

1.5 Mastering the KR 3

1.6 Reference point mastering

1.7 Unmastering an axis

1.8 Mastering of master/slave drives

-- +

2 Calibration

2.1 Fundamentals

1.

2.

3.

10 kg

100 kg

2.2 Tool calibration

Program Calibration by...

...

P1

P2 P4

P3

Z

Z

X

Y

...

...

...