With a fully patched game (1.73.57.1030) I thought I'd try again with the robot vacuum last night; it had been several months since I last tried them after I had all the annoying bugs mentioned throughout this thread.
Before I tried directing my sim to even use the robot vacuum, I had him fully upgrade both the vacuum and the dock. Then I had him set it for auto cleaning every 6 hours and then start the cleaning cycle. Lo and behold it worked PERFECTLY! 🙂
*PAY ATTENTION TO PLACEMENT*:
I made sure that the BACK of the 'dock' was Not Against any wall; it was a half square OUT from the wall and that alone seemed to make all the difference.
Hope this Helps! 🙂
I still have the problem with the robot vacuum placing it half a tile away from the wall does not work.
