Hello Guys,
Please i want to know why sometimes we should send or receive position from plc to robot ? I know how to do it using GIO but i never come across to use it .
Regards,
Hello Guys,
Please i want to know why sometimes we should send or receive position from plc to robot ? I know how to do it using GIO but i never come across to use it .
Regards,
I've never come across a use case in my projects to send/receive the entire position.
If I want the PLC to know the robot is in a certain position, I will setup reference positions with DOs. If the PLC needs to calculate an offset, I will just send that offset value as a register.
Many times I have seen questions here about exchanging coordinates, it was because they created paths offline and then wanted to stream them to the robot. And many times it was from students.
In wild life I can remember only one case where I used absolute coordinates from PLC to robot. Was a screwing application with unknown amount of different work pieces, they wanted to set parameters for the screwing positions on HMI. Most time it's only transferring offsets like HawkME said.
You often need to exchange position data from/to robot when dealing with an external machine vision system, e.g. when doing a bin picking or something alike.
In the case of a stationary mounted vision sensor, the machine vision system will give a picking position your robot needs to reach in order to pick the workpiece; in this case you need to receive positions. When the vision system sensor is mounted on the robot tool, the robot should also send its "acquisition position" (i.e. the position where the vision system's trigger was commanded) so that the vision system can calculate its frame position with respect to the robot frame.
When using a machine vision system you typically need to perform an "Hand-eye calibration" (https://en.wikipedia.org/wiki/Hand%E2%80%93eye_calibration_problem) and this requires the machine vision system to know robot positions (so a robot -> vision channel is mandatory, especially if you have an automated hand-eye calibration routine). The vision -> robot channel is needed to use the vision system's outputs.
thank you guys for you explication, appreciate that
As an example of PLC <-> Robot position exchange, I've done several applications of applying sealant and then performing a visual inspection. The visual image was displayed on a HMI and the set-up person was given the ability to modify robot PRs that the robot was using as offsets to the position at which the sealant was applied. The PLC read the offset PR using a explicit read instruction, modified the values based on the setup person's desires, and then wrote them back using a explicit write to that offset PR. The part had about 20+ locations getting the sealant applied.
Worked well, I've done a half-dozen of these using a M20 robot, AB Guardlogix PLC, Panelview PC/HMI, and a Cognex Insight camera.
As an example of PLC <-> Robot position exchange, I've done several applications of applying sealant and then performing a visual inspection. The visual image was displayed on a HMI and the set-up person was given the ability to modify robot PRs that the robot was using as offsets to the position at which the sealant was applied. The PLC read the offset PR using a explicit read instruction, modified the values based on the setup person's desires, and then wrote them back using a explicit write to that offset PR. The part had about 20+ locations getting the sealant applied.
Worked well, I've done a half-dozen of these using a M20 robot, AB Guardlogix PLC, Panelview PC/HMI, and a Cognex Insight camera.
buen dia
quiero hacer algo parecido a lo que comentas con un robot r-2000ic 210f con equipo nordson y una sistema de vision coherix
me puedes compartir los archivos que tienes para darme una idea de donde empezar?
Gracias
yes, we have penel view plus 7 and PLC studio 5000