So since the KCP2 pendants are becoming an increasingly expensive spare/replacement, and because I'm an electrical engineer with a lab at my disposal, I've decided to do something a bit on the extreme side.
I'd like to reverse-engineer and (almost) completely emulate the KUKA KCP2 pendants, in their entirety. Internally, they're odd beasts - they have two logically separate(but physically one) connections to the digital ESC card, which is a CANBus network configured in an extremely odd ring topology. The pendant and ESC board communicate with a series of packets that describes the status of all the safety circuitry(integrity of the ring, dead man switches), as well as two additional layers - one, between the ESC and the MFC in terms of hierarchy, where the physical keys(drives, estop, +/- axis keys, space mouse) are, and the highest level, which is transferred through the MFC card up to VxWin(a proprietary KUKA version of VxWorks designed to run concurrently with Windows) and actuates the softkeys in the HMI.
The display is connected using a proprietary protocol based on obsolete AMD TAXIchip technology, which is driven by an incredibly abused, but nonetheless standard CHIPS PCI graphics adapter(gotta give the German designers props, they managed to make it do what it was never supposed to). I have deemed this portion of the KCP system unnecessary to emulate, because replacing the expensive and very easy to kill KVGA card with a standard AGP, PCI, or even ISA graphics adapter gives automatic boot priority to the video output, meaning you could use any regular VGA display and retain 100% of the functionality, with none of the dangers, expenses, or mess - aside from, maybe, not being able to use an actual pendant due to the aforementioned proprietary protocol.
This project is to emulate only the pendant - not the entire safety system(though that, I suspect, would be just a few bytes away). The goal is not to compromise safety, but to let people with incomplete systems run them headless - to be able to turn drives on and have a third-party dead man switch without spending thousands of dollars. How the user implements it would dictate the overall safety, but I see no reason why one couldn't replicate the pendant functionally, just not aesthetically, to maintain complete safety(with estop, deadman, and drives control) at the cost of liability. In some situations, extreme safety measures aren't required - for example, when a small robot is physically unable to interact with and damage items, or reach and harm humans.
If you'd like to help, there's only one thing I need at this moment - a KCP2 std. ed05, with the part numbers of 00-130-547 or 00-131-239. I am almost certain that these particular pendants are easily converted into any other KCP2 variant, ed05 or otherwise. I'm unsure whether the more modern ed05 VKCP2 variants are convertable, but those could potentially work as well.
If anyone has a spare of either one of those part number pendants, please let me know.