Proximity detection system and method and collision avoidance system and method using proximity detection

摘要

The invention relates to a proximity detection system. The invention provides a proximity detection system comprising a generator that generates a magnetic field that establishes a boundary, where the generator is capable of receiving radio frequency signals. Also provided is a radio frequency device that sends radio frequency signals, the radio frequency device being capable of sensing the magnetic field and generating a radio frequency response. In the proximity detection system, the generator generates the magnetic field for a first predefined time period, and thereafter senses for a radio frequency response signal from the radio frequency device within a second predefined time period. The invention also provides for shaping proximity detection zones by overlaying magnetic field boundaries to produce a different boundary. The invention also provides for varying the strength of magnetic fields by adjusting a width of a timed pulse.

主权项

1. A proximity detection system for complex work environments for detecting the presence of a worker or operator wearing an alarm device in a potentially hazardous location at a work site, the proximity detection system comprising:
a plurality of vehicles; each of the vehicles having a plurality of magnetic field generators; each of the plurality of magnetic field generators adapted to generate ping pulses of a magnetic field; a plurality of alarm devices located on the persons of a plurality of workers and/or operators, each device being adapted to sense the ping pulse magnetic field in which the device is located and generate an echo response signal after a predetermined echo time delay; the plurality of magnetic field generators being adapted to receive the echo response signals, and in response to receiving the echo response signal during a window of time corresponding to the predetermined echo time delay, to generate a burst of the magnetic field ping pulses, the burst of ping pulses being of predetermined duration and being generated at semi-random time intervals; the plurality of magnetic field generators being adapted to, in response to receiving the echo response signal during a window of time corresponding to the predetermined echo time delay for each of the ping pulses of the burst, identify that the device is located in a particular magnetic field generated by one of the plurality of magnetic field generators.