Mitsubishi Electric MELFA CR800-D Series User Manual page 81

(PVS calibration)
ＰＶＳＣａｌ
[Function]
Using the calibration data (parameters VSCALB 1 to 8) set by the vision calibration function, convert the
image coordinates of the vision sensor to the robot world coordinates.
[Format]
<Position variables> = PVSCal (<Calibration number>,<Vision X>,
<Position variables>
<Calibration number>
<Vision X>
<Vision Y>
< Vision θ>
<Reference Position Variables> Specify the reference position as s position constant or position
[Reference Program]
1 'Start the target vision sensor with Open/Print/Input command to substitute the acquired image
coordinate [pixel] for numeric variable.
2 'MX=X [pixcel] of the vision sensor
3 'MY=Y [pixcel] of the vision sensor
4 'MT=θ [deg.] of the vision sensor
5 PVS=PVSCal(1,MX,MY,MT)
coordinate with Calibration 1.
6 PVS.Z=PDST.Z
7 Mov PVS, -50
8 Mvs PVS
[Explanation]
(1) Using the vision calibration data (parameters VSCALB 1 to 8), convert the image coordinates of the vision
sensor to the world coordinates of the robot.
Please use the automatic calibration function or the 2D vision calibration function of RT Toolbox 3
beforehand to set the parameters VSCALB 1 ~ 8 used for coordinate conversion.
(2) If the calibration numbers other than 1 to 8 are set, error L3110 (Arg. value range over) occurs.
(3) If the numbers of argument are not either four or five, error L3120 (No. of arg. is over) occurs.
(4) If the type of arguments is different, error L3810 (Different argument type) occurs.
(5) If calibration data is calculated with VSRegCD, coordinate conversion taking into consideration the
relationship between the robot coordinates and the hand system of the image coordinates is automatically
carried out.
[Related instructions]
VSRegCD
[Related parameter]
VSCALB1 to 8
<Vision Y>,<Vision θ> [,<Reference Position Variables>])
Specifies the position variable to assign.
Returns the robot world coordinate for the calculation result of the
coordinate conversions.
Specify the target calibration number.
Setting range: 1 to 8
X pixel coordinate of the vision sensor. [pixel]
Y pixel coordinate of the vision sensor. [pixel]
θ pixel coordinate of the vision sensor. [deg.]
variable.
When attaching a camera to the hand, specify the robot position (at
the time of the image recognition) where the image is recognized
with the vision sensor as a reference position. The relative
calculation is performed as follows.
<Robot position at the time of the image recognition>*<Calculation
result of the coordinate conversion>
When omitted, the absolute coordinate is set.
'Changes the image coordinate to the robot (world)
'Specifies Z height.
'Moves to a position 50 mm above the calculated position.
'Moves to the calculated position.
4 Calibration assistance function
Robot Programming Language 4-71