Optical position marker apparatus

• US 20090180667A1
• Filed: 01/13/2009
• Published: 07/16/2009
• Est. Priority Date: 01/14/2008
• Status: Active Grant

• Current Assignee: TotalTrax, Inc.
• Original Assignee: Sky-Trax Incorporated (TotalTrax, Inc.)
• Inventors: Brisbin, Sarah M., Martine, Kimberly M., Mahan, Larry G.
• Granted Patent: US 8,210,435 B2
• Time in Patent Office: Days
• US Class Current: 382/103
• CPC Class Codes: G01S 5/163 Determination of attitude using inertial means G01C9/00; control of attitude G05D1/49

Abstract

An apparatus for marking predetermined known overhead positional locations within a coordinate space, for viewing by an image acquisition system. The apparatus comprises a plurality of marker tags, grouped in one or more rows, each row having an axis, each row being supported by a row support. Each marker tag comprises an optically opaque, dark colored corrugated substrate, substantially rectangular in shape. A label having a unique machine-readable barcode symbology printed thereon is positioned centrally on the substrate so that a dark colored border of the substrate surrounds the label. Each row support comprises a first support cord and a second support cord. The first support cord supports a first lateral edge of the marker tags in a row group in a fixed, spaced-apart positional arrangement. The second support cord supports the second lateral edge of the marker tags in the row in a slidable support arrangement.

Claims

1. An apparatus for marking predetermined known overhead positional locations within a coordinate space, for viewing by an image acquisition system, the apparatus comprising:

a plurality of marker tags, the marker tags being grouped in one or more rows, each row having an axis, the marker tags in a row group being supported by a row support,

each marker tag comprising;

an optically opaque, substantially stiff substrate, substantially rectangular in shape,

a label positioned centrally on the substrate, each label having a unique machine-readable barcode symbology printed thereon, a border of the substrate surrounding the label;

each row support comprising;

a first support cord for supporting a first lateral edge of the marker tags in a row group in a fixed, spaced-apart positional arrangement, and

a second support cord for supporting the second lateral edge of the marker tags in the row group in a slidable support arrangement,

the first support cord being attached to an overhead support structure at each end with a tensioning device, the support cord being drawn to a predetermined tension, thus establishing a substantially straight first lateral row edge, the tensioning devices on the first support cord permitting precise positioning of the marker tag group along the row axis;

the second support cord being attached to the support structure at each end with a tensioning device, the support cord being drawn to substantially the same tension as the first support cord, so that the marker tags are supported in a substantially horizontal plane, the slidable support of the second lateral edges allowing the marker tags of a row group to align along the first lateral edges.

2. The apparatus of claim 1 wherein each marker tag substrate is comprised of a dark colored substantially stiff corrugated material so that a dark colored border surrounds the barcode label.

3. The apparatus of claim 2 wherein the first support cord is threaded through at least two fasteners attached to the substrate adjacent to the first lateral edge, at least one of the fasteners being attached tightly to the support cord in a fixed arrangement, thus establishing the fixed, spaced-apart positional arrangement of the markers within the row group.

4. The apparatus of claim 3 wherein the second support cord is threaded loosely through at least two support fasteners attached to the substrate adjacent to the second edge to support the edge in a slidable manner.

5. The apparatus of claim 2 wherein:

the corrugations of each substrate are aligned with the row axis,

the first support cord is threaded through a corrugation channel adjacent to the first lateral edge of each substrate, and

a fastener is attached tightly to the support cord immediately adjacent to each end of the corrugation channel, thus establishing the marker tags within the row group in the fixed, spaced-apart positional arrangement.

6. The apparatus of claim 2 wherein the second support cord is threaded through a corrugation channel adjacent to the second edge of the substrate to support the edge in a slidable manner.

7. The apparatus of claim 2 further comprising a first spreader bar to hold the first ends of the first and second support cords at a fixed spacing corresponding to the spacing of the corrugation channels adjacent to the first and second lateral edges of the marker tags and a second spreader bar to hold the second ends of the first and second support cords at the fixed spacing.

8. The apparatus of claim 2, wherein the substrate is a black polypropylene corrugated sheet material.

9. An apparatus for marking predetermined known overhead positional locations within a coordinate space, for viewing by an image acquisition system, the apparatus comprising:

a plurality of marker tags, the marker tags being grouped in one or more rows, each row having an axis, the marker tags in a row group being supported by a row support, each marker tag comprising;

an optically opaque, dark colored corrugated substrate, substantially rectangular in shape,

an adhesive-backed label positioned centrally on the substrate, the label of each marker tag having a unique machine-readable barcode symbology printed thereon, a dark colored border of the substrate surrounding the label;

each row support comprising;

a first support cord threaded through a corrugation channel adjacent to the first lateral edge of each substrate for supporting the first lateral edge of the marker tags in a row group in a fixed, spaced-apart positional arrangement, and

a second support cord threaded through a corrugation channel adjacent to the second lateral edge of each substrate for supporting the second lateral edge of the marker tags in the row group in a slidable support arrangement,

a stiff spreader bar at each end of the row group to hold the first and second ends of the first and second support cords at a fixed spacing corresponding to the spacing of the first and second lateral edges of the marker tags,

the first support cord being attached to an overhead support structure at each end with a tensioning device, the support cord being drawn to a predetermined tension, thus establishing a substantially straight first lateral row edge, the tensioning devices on the first support cord permitting precise positioning of the marker tag group along the row axis,

the second support cord being attached to the support structure at each end with a tensioning device, the support cord being drawn to a predetermined tension, substantially the same as the tension of the first cord;

so that the marker tags are supported in a substantially horizontal plane, the labels being readable from below, the slidable support of the second edge of the marker tags allowing the marker tags to align along the first lateral edge along the row axis.