A PIR sensor detects moving objects that have a temperature different from the environment. May work for some cases, but is imho not a good detector for movement n this case as it is abot detecting movement ob the object itself
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An accelerometer mounted to the chassis of the unit to be protected is a suitable solution, but needs evaluation of the sensor signal by a microcontroller. Probably way too advanced.
Many toys use an elastic spring that connects to a stationary contact when the toy is moves (here's a more "professional"
model for DIY makers). This kind of sensor is reasonably easy to handle as it is essentially a momentary switch. This can be used to trigger a monostable multivibrator based e.g. on a 555 timer chip ("negative trigger pulse" in this
circuit diagram). The timing will be a bit inaccurate for such a long time, but 5 min give or take a few seconds is doable.