A power cutting tool having a movable blade, such as a table saw,
comprising a radar sensing system for movement of an object in a region
near the blade is disclosed. The radar sensing system emits a radio
frequency wave and receives wave energy reflected by the object. The
system measures the Doppler shift of the received wave energy to detect
the presence of a fast moving object in a zone near the blade. When such
a condition is detected, a reaction system can be activated to mitigate
the condition.