I know you have to have a personal roboport to enable it. I do, it's in my modular armor. It's with batteries and solarpanels (and it's daytime). And I have construction robots. But I can't click the "Enable personal roboport" button in the shortcut bar. Pressing Alt+H doesn't enable it either.
This might be helpful. I used the console code to...
/unlock-shortcut-bar
...before I had researched robot technology. But for some reason the roboport button is disabled no matter how many times I click it.