How do I tell the robot UR20 the size of the tool? And is there any way we can configure it so that if homing starts it avoids obstacles (obstacles are dynamic)? What if the radius of the attached tool is more than 300mm?
In short I want the robot to know the size of the tool, so when homing starts it avoids the obstacles which are dynamic.
The robot is not “smart” per se. It does what you program it to do. It will also drive the tool into the robot arm, if you make a waypoint with a path through itself or close to itself.
How would the robot know where the obstacles are located, if they’re dynamic? Have you installed a camera or something? 
A safe home routine is usually programmed with waypoints that allow the robot to return home without colliding with anything - be they static or dynamic.
The tool radius which can be set in the Safety settings will stop the robot from moving that sphere through any safety planes, but that’s it.
Ok so my thought pattern was maybe if it was aware of its 3d surroundings, maybe using something like RoboDK.
I mean homing is still possible, I’d just have to make cases for each condition, I was hoping there was a feature that would do it for me lol
Well. It could be possible for software to create the path for the robot, but, in my opinion, it sounds like way too much work compared to just making some waypoints in the program and looking at conditions, as you say yourself.
There’s no built-in feature for this, and I’m not aware of any 3rd party solution that does it.
Maybe someone else can contribute with something.
At this point of the project, yes i would do that