Uploaded by Erika Florence

ADVM 163 - Week 6 Lecture

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Chapter 9 - Tool Frames
● Frames describe location
and orientation of a position
with respect to an origin.
● 3 frames affect robot
positioning:
○ World
○ User
○ Tool
Chapter 9 - Tool Frames
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Default tool frame is the faceplate
on J6
Default tool frame’s Z-axis is away
from the faceplate and X-axis
pointing “upward”.
When a point is recorded, it is
always referencing the current user
and tool frame.
The active tool frame can be set by
pressing SHIFT+COORD on the
TP, or through the frames menu, or
from with in a program...
UFRAME_NUM=, UTOOL_NUM= .
Chapter 9 - Tool Frames
● For gripping tools, use a “pointer” tool to help
teach the tool frame.
● 4 common methods of teaching a tool frame:
○ 3-point method (easiest, requires a TCP
tool)
○ 6-point method (allows you to change the
orientation of the tool frame)
○ Direct Entry (if you know the tool
dimensions from the faceplate)
○ Vision TCP
● To set up a tool frame, press MENU and then
select Frames, and then options appear at the
bottom.
Chapter 10 - Offset (User) Frames
● User Frames are based off of the World
Frame
● User Frames can be taught at any location
and any orientation
● Positions are taught with respect to a User
Frame (& Tool Frame!)
● SHIFT+COORD will allow you to change
the active frame (or MENU → Frames)
Chapter 10 - Offset (User) Frames
● Four common methods for teaching a User
Frame
○ 3-Point Method
○ 4-Point Method
○ Direct Entry
○ Automatic Grid Set
● 4 pt or Automatic Grid Set are recommended to
teach a user frame used in Vision processes
● With 4-Pt, choose a starting point (Origin), then
jog the robot in X-direction, then Y-direction,
and finally select the System Origin.
Chapter 11 - Calibration Frame
● A user frame must be taught that is used with a
vision process.
● It establishes a relationship between the
camera’s view and the user frame of the robot.
● Use the same calibration grid to teach the
frame as you use to calibrate the camera
● Three large dots will be recognized as the
X-axis by the camera.
● Two large dots will be recognized as the Y-axis
by the camera.
● The intersection of these lines will be
recognized as the system origin.
Chapter 11 - Calibration Frame
● Use the FOUR Point
method to teach the
User frame
● Robots with gripper will
need a pointer tool to
help make this as
accurate as possible.
(Z value may need to be
adjusted when selecting
the System Origin)
Chapter 11 - Calibration Frame
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Many robots come with a
feature called the Automatic
Grid Set which will teach
itself the user frame.
This feature is found in the
iRVision menu selection
under iRVision Utilities.
The robot will move around
and take pictures to
determine the User Frame
for the Grid and a Tool
Frame for the camera.
Chapter 12 - 2D Calibration
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To perform any motion program that uses a Vision
Process, the vision system MUST be calibrated.
Calibration establishes the camera’s mm/pixel
scale and its relationship to the robot.
Application Frame: only change this is the robot’s
vertical axis is different from camera’s axis.
Cal. Grid Frame:
○ Robot Mounted Camera: This is the user
frame you taught and will use to do a motion
program.
○ Fixed Mounted Camera: This is the Tool
Frame of the robot holding the Cal. Grid.
Chapter 12 - 2D Calibration
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Number of planes:
○ 1 Plane = you type in all the distance and
focal length info
○ 2 planes = have it determine all the info
(this gives best results) - does require to
do a SNAP-FIND and set the data for the
2 planes. 2nd plane should be at least
100mm away along the Z-axis.
Projection: Choosing Perspective will allow
the process to adjust for Z-Height differences
in parts.
Check Calibration Point data for any
erroneous values.
Chapter 12 - 2D Calibration
Chapter 13 - 2D Single View Vision Process
● This process will produce X, Y, and R
offset data that can be used in a motion
program.
● The offset data basically just offsets the
frame that was used in calibration.
● Two main types of offsets can be
accomplished:
○ Fixed Frame Offset: can be used
with either fixed cameras or robot
mounted cameras.
○ Tool Offset: more useful for fixed
mounted cameras.
Chapter 13 - 2D Single View Vision Process
● To create a vision process for robot
guidance… start the vision setup
process and choose the 2-D Single
View Vision Process and give it a
name.
● Process Tree consist of:
○ Snap Tool (version dependant)
○ GPM Locator Tool
○ Offset Data Calculation Tool
(version dependant)
Chapter 13 - 2D Single View Vision Process
● After Snap Tool and GPM Locator are
setup, then complete the Offset Data
Calculation Tool.
● Ref. Data: set this to Static for one part.
Set to Model ID if you need to identify
different parts with different Z heights.
● Part Z height: taller the object, the more
important this is!
● Ref Pos.: This is the kicker!! Set this and
then DON’T move the part when you
teach points in your program.
○ This location will become the “zero”
location of your part in this frame
Chapter 13 - 2D Single View Vision Process
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