I've been trying various Marlin configurations, I've considered buying different electronics (for example a Smoothieboard or something) and I've looked into GRBL, but I've yet to find anything that seemed like it would be better. I've also been trying to get a linux dual boot running so I could try ROS, but god DAMN Linux is just not my friend. I can't even get the dual boot working, much less actually use it for anything.
So currently, I'm trying to make a simple program from scratch just to test it. I'm not a great programmer, so it might not get very far, but it would be nice to have some software that is actually useful for the application and somewhat flexible.
The Raspberry Pi/ROS solution sounds great, especially to allow integration of things like computer vision and stuff, but as mentioned, I have a long way to go before I can use Linux efficiently.
I haven't tried ROS, but it sounds like the closest thing to ideal based on their wiki - I'd like something universal and flexible. I'm finding Marlin difficult to configure to anything but 3d printers, and GRBL isn't as straight forward as it used to be to install either. I use GRBL on a CNC router I built, but I'm not sure how to install it and configure it.
It's particularly difficult because it's a SCARA configuration. I've used Marlin previously for a cartesian prototype, but I feel that SCARA is superior when trying to lower the cost while maintaining good repeatability and rigidity.
Lots of issues = lots of reasons to cooperate!
I'm excited to see you get further with the robot you showcased - are you planning on 3d printing the "arms" as well?