Method for laser-based two-dimensional navigation system in a structured environment

Patent · Sun Jan 01 00:00:00 EST 1989

OSTI ID:866812

Boultinghouse, Karlan D ^[1]; Schoeneman, J Lee ^[2]; Tise, Bertice L ^[2]

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1. Sandia Park, NM
2. Albuquerque, NM

A low power, narrow laser beam, generated by a laser carried by a mobile vehicle, is rotated about a vertical reference axis as the vehicle navigates within a structured environment. At least three stationary retroreflector elements are located at known positions, preferably at the periphery of the structured environment, with one of the elements having a distinctive retroreflection. The projected rotating beam traverses each retroreflector in succession, and the corresponding retroreflections are received at the vehicle and focussed on a photoelectric cell to generate corresponding electrical signals. The signal caused by the distinctive retroreflection serves as an angle-measurement datum. An angle encoder coupled to the apparatus rotating the projected laser beam provides the angular separation from this datum of the lines connecting the mobile reference axis to successive retroreflectors. This real-time angular data is utilized with the known locations of the retroreflectors to trigonometrically compute using three point resection, the exact real-time location of the mobile reference axis (hence the navigating vehicle) vis-a-vis the structured environment, e.g., in terms of two-dimensional Cartesian coordinates associated with the environment.

• Research Organization: AT&T
• DOE Contract Number: AC04-76DP00789
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4796198
• OSTI ID: 866812
• Country of Publication: United States
• Language: English

Related Subjects

method
laser-based
two-dimensional
navigation
structured
environment
power
narrow
laser
beam
generated
carried
mobile
vehicle
rotated
vertical
reference
axis
navigates
stationary
retroreflector
elements
located
positions
preferably
periphery
distinctive
retroreflection
projected
rotating
traverses
succession
corresponding
retroreflections
received
focussed
photoelectric
cell
generate
electrical
signals
signal
caused
serves
angle-measurement
datum
angle
encoder
coupled
apparatus
provides
angular
separation
lines
connecting
successive
retroreflectors
real-time
data
utilized
locations
trigonometrically
compute
resection
exact
location
hence
navigating
vis-a-vis
terms
cartesian
coordinates
associated
reference axis
electrical signals
electrical signal
laser beam
signal caused
rotating beam
corresponding electrical
mobile vehicle
rate corresponding
photoelectric cell
angle encoder
/701/180/250/318/356/901/