A walking stick navigator (WSN) apparatus and process comprises an aided INS
(AINS)
on a staff assembly similar in operation and appearance to a GPS survey instrument.
However, when GPS is available, the AINS is aided by GPS data, and the surveyor
manipulates the staff assembly like a standard GPS survey instrument. When GPS
is not available due to signal obstruction, the surveyor manipulates the staff
assembly as a walking stick. A switch means coupled to the lower end of the staff
assembly provides a stationary interval signal when the surveyor plants and holds
the WSN on the ground while walking. An input process is coupled to the AINS output
signals and to the stationary interval signals and provides at least one aiding
input signal to the AINS for each successive stationary interval, thereby allowing
the AINS to control its velocity error and position drift during a GPS outage.