Deadlock

'Bzzz! Bzzz!' The alarm went off, and Susan Calvin rolled over. It was 6:30 in the morning, and RoboTimer® had done its job admirably, waking her up to the second of the time that it had been factory-programmed. Unfortunately, it hadn't been set to the correct date, and when it announced 'Saturday, December 14th! Good morning!' in a load cheery tone, she groaned out load with the realization that it was Saturday, and after that affair with the hyperdrive motor, she wanted to sleep in, since it she had just come back to earth.
'I hate this stupid robot!' she yelled out loud, th…