US 5,111,401 AGranted

Navigational control system for an autonomous vehicle

AssigneeThe United States of America as represented by the Secretary of the Navy

InventorsHobart R. Everett, Jr., Gary A. Gilbreath, Robin T. Laird

Life of this patent

Estimating the term…

Loading patent…

Abstract

A navigational control system directs an autonomous vehicle to travel along a floor from a first location to a destination within an environment, and includes a propulsion module having a processor that receives navigation control signals for directing the motion of the module and provides position signals. At least one reflective, encoded stripe is applied to the floor of the environment. If stripe detecting means, mounted to the module, detects the stripe, recognition signals are provided. Ranging means mounted to the module measures the range between the vehicle and any object within a predetermined distance of the vehicle. A host computer determine an initial path for the vehicle to follow in order to reach the destination; provides the navigation control signals to the processor; receives data from the processor for determining an estimated dead-reckoning position of the vehicle; and receives the recognition signals for directing the vehicle to follow the stripe if any of the coordinates of the stripe are coincident with the coordinates of the initial path. The position estimation of the vehicle is updated by the host computer as the vehicles travels along the initial path. The updated position is functionally related to the coordinates of the detected region of the stripe and to the estimated dead-reckoning position. If the ranging means measures an obstruction blocking the initial path, the module is directed to avoid the obstruction.

Claims23

Dependent claims

A navigational control system for directing an autonomous vehicle to travel along a generally planar surface, such as a floor, from a first location to a destination within an operating environment, comprising:

an autonomous vehicle including a self-propelled and steerable propulsion module providing position signals corresponding to a dead-reckoning determination of a position and bearing of said module with respect to a reference position;
at least one long, narrow guidepath stripe applied to said surface of said environment to define a desired pathway having predetermined coordinates along which said module may be selectively guided, said guidepath stripe encoded with a plurality of displacement markers positioned at predetermined intervals along the length of said guidepath stripe, said markers having predetermined coordinates;
stripe detecting means mounted to said module for detecting said guidepath stripe and said displacement markers, and for providing recognition signals when said stripe detecting means detects said guidepath stripe and for providing recognition signals when said guidepath stripe detection means detects one of said displacement markers;
ranging means mounted to said module for measuring the range between said module and any object and for providing range signals corresponding to said measured range;
and
processing means for determining an optimal path for said module to follow to said destination, said processing means:
coupled to receive said position signals for monitoring said dead-reckoning determined position of said module along said path;
coupled to receive said range signals for revising said path in order to avoid an obstacle blocking said path;
and coupled to receive said recognition signals for revising said dead-reckoning position of said module into an updated position;
said processing means for revising said optimal path in response to said updated position;
and for providing navigational control signals to guide said module along said optimal path.

8 more elements

an autonomous vehicle including a self-propelled and steerable propulsion module providing position signals corresponding to a dead-reckoning determination of a position and bearing of said module with respect to a reference position;
at least one long, narrow guidepath stripe of reflective material applied to said surface of said environment to define a desired pathway having predetermined coordinates along which said module may be selectively guided, said guidepath stripe encoded with a plurality of displacement markers positioned at predetermined intervals along the length of said guidepath stripe, said markers having predetermined coordinates, said guidepath stripe contrasting with said floor;
stripe detecting means mounted to said module for detecting said guidepath stripe and said displacement markers, and for providing recognition signals when said stripe detecting means detects said guidepath stripe and for providing recognition signals when said guidepath stripe detection means detects one of said displacement markers;
ranging means mounted to said module for measuring the range between said module and any object and for providing range signals corresponding to said measured range;
and
processing means for determining an optimal path for said module to follow to said destination, said processing means:
coupled to receive said position signals for monitoring said dead-reckoning determined position of said module along said path;
coupled to receive said range signals for revising said path in order to avoid an obstacle blocking said path;
and coupled to receive said recognition signals for revising said dead-reckoning position of said module into an updated position;
said processing means for revising said optimal path in response to said updated position;
and for providing navigational control signals to guide said module along said optimal path.

8 more elements

an autonomous vehicle including a self-propelled and steerable propulsion module providing position signals corresponding to a dead-reckoning determination of a position and bearing of said module with respect to a reference position;
at least one long, narrow guidepath stripe applied to said surface of said environment to define a desired pathway having predetermined coordinates along which said module may be selectively guided, said guidepath stripe encoded with a plurality of displacement markers positioned at predetermined intervals along the length of said guidepath stripe, said markers having predetermined coordinates, said guidepath stripe is invisible when irradiated with visible light and fluoresces when irradiated with ultraviolet light;
stripe detecting means mounted to said module for detecting said guidepath stripe and said displacement markers, and for providing recognition signals when said stripe detecting means detects said guidepath stripe and for providing recognition signals when said guidepath stripe detection means detects one of said displacement markers;
ranging means mounted to said module for measuring the range between said module and any object and for providing range signals corresponding to said measured range;
and
processing means for determining an optimal path for said module to follow to said destination, said processing means:
coupled to receive said position signals for monitoring said dead-reckoning determined position of said module along said path;
coupled to receive said range signals for revising said path in order to avoid an obstacle blocking said path;
and coupled to receive said recognition signals for revising said dead-reckoning position of said module into an updated position;
said updated position functionally related to said position encoded in said position signals and to said position corresponding to said location associated with said recognition signals;
said processor means for revising said optimal path in response to said updated position;
and for providing navigational control signals to guide said module along said optimal path.

9 more elements

Dependencies are inferred from the claim text.