this article and video, we will show you how to do a simple vision guided pick and place
application. Let's take a look.
first step in this process is calibrating the robot so the camera knows actual real-world
coordinates. You must use the vision cards that were supplied with your
robot. There is a large card for distances between 2 3/4" and 15
3/4" and small card for distances between 2 3/4" and 7
place the vision card at the height of the top of the product you will be
locating. So, in this example I am detecting these blocks, I will put the
blocks on the surface and then place the card on top of the blocks to perform
move the robot to the vision area at the height you want it to search. The
height must be a minimum of 2 3/4 inches from camera to calibrate this
card. Press the vision button. The vision block should be added to
it's time to calibrate. Click on the pencil icon on the vision
block. Click on arrow then the plus button. Give the vision job a
name. My example simply uses locate. The live camera image will
eventually load. Be sure the calibration board is centered within the
field of view of the camera. Unless you are using dedicated external
lighting, I would suggest turning on the robot’s internal ring light. Go
to IO and scroll down to Camera Module. Press the button to turn the light on.
double click calibration and choose automatic.
ready, press the PLAY button on the robot stick. Please note the robot
will start moving at this time.
completed with step one press ok to go to the next step.
the calibration board is centered within the field of view of the camera and
press next, then OK.
robot will now perform auto calibration. Press the play button when ready.
The robot will again move.
complete the software will give an error value. This basically implies
how much potential error could be in the vision system. Press yes to
your calibration a name and press save and yes to exit.
it's time to create a vision tool to locate an object. I've placed my
block in the field of view. Click on task designer. Choose Fixed
Point. Click on the calibration you just created. Press and hold
the + button on the robot stick to move the robot to calibration
position. Once in place, the software will load the vision tools.
we add matching tool, let's turn on the light again. Go to IO and scroll
down to Camera Module.
the black upper tool bar, choose the locate tools. This example uses the
pattern matching shape tool.
on select pattern. Click and drag the box around the object you are wanting to
detect. The tool has now been trained. You may notice the vision tool
picked up some of the scratches in the block. These scratches will need to be
deleted as not all objects may have these. Click on edit pattern.
Click on the eraser tool and touchup all blemishes on the block. Press
the arrow to update the pattern.
needed, adjust the minimum score from 0-1 with 1 being most sensitive.
set your search range. Anywhere in this box the camera will look for your
pattern. Adjust rotational range if you want to limit how much rotation the
object has before the robot will pick up the part. Scaling range will
allow size differences in your pattern with 1 being the same size and 1.5 being
1 1/2 times larger.
you can see, I can rotate the object and the camera locates it.
next step is important. You need to be sure you save properly. Do
not press the green arrow. If the save icon is slightly greyed out, press
the left arrow in the black bar once. Now press the save icon and follow
that the vision is saved, it is very important that you do not move the block
until you have taught the robot that position.
teach the pick position, we need to program the light to turn on in your
project flow. Drag the locate tool down a bit. Click on the start
block and press the bottom "X". From the left tools, click on
set and drag below start and locate. Then you can reconnect your blocks.
To turn the light on, click on set1 and under digital I/O and light
module click till you see the check box. After we locate, the light can
be turned off. For set2, click on digital IO and click on light module
till you see an "X".
with the gripper open, move the robot to the position of the block. Once
in position, press the point button on the robot. If you need to, you can
edit motion setting so it is a line or way point. You can also give the
point a name by going to point manager and editing P1.
that you have taught the pick position you are ready to move and teach the
place position. Press the grip button to grip the block.
the robot to the place position, push the point button, and then the grip
button to release.