Mark Allen Erickson

US Patent:

49985523, Mar 12, 1991

Filed:

Sep 12, 1989

Appl. No.:

7/406233

Inventors:

Mark R. Niksic - Lakewood CO
Mark E. Erickson - Oakland CA

Assignee:

T. A. Pelsue Company - Englewood CO

International Classification:

E04H 1536

US Classification:

135102

Abstract:

A self supporting collapsible tent structure having a tension bearing polygonal shaped floor member defining a first tent level, a plurality of hub members each carrying a plurality of sockets which are pivotal about axes which are co-planer and are interrelated one to the other as the sides of polygon, a series of said hub members disposed in a plane at a second tent level which is spaced apart from said first tent level and whose sockets are pivotal in a first direction, and additional series of said hub members disposed in a plane at a third tent level which is spaced apart from said second tent level and whose sockets are pivotal in a second direction, opposite to the said first direction, a single, apex forming hub member disposed at a fourth tent level and whose sockets are pivotal in said first direction, a first plurality of compression rods, the ends of which are seated in the said sockets of the hub members in slightly curved polygonal planes defined and bounded by the rod members and a second plurality of compression rods, one end of which are seated in sockets of the hub members at the second tent level and the other end of which are connected to the perimeter of the floor member.

US Patent:

45368473, Aug 20, 1985

Filed:

Dec 30, 1982

Appl. No.:

6/454590

Inventors:

Mark R. Erickson - Northglenn CO
James A. Kaehler - Littleton CO

Assignee:

Atlantic Richfield Company - Los Angeles CA

International Classification:

G06F 1546
G05D 112
F24J 302

US Classification:

364516

Abstract:

An improvement in a system and method of controlling a body to maximize the amount of solar energy received by a collector by moving the body in azimuth and elevation by respective DC motors having connected therewith ring magnets and Hall Effect Devices for signalling the degrees, or steps of rotation. The at least one body may be a collector, per se, or a plurality of heliostats in an array reflecting onto a central collector. A central computer calculates a commanded position for particular time of particular day for the particular location of the body. A microprocessor incorporating respective software and hardware then calculates the position for the heliostat to be in terms of the number of signals from the Hall Effect Device, compares the number of signals from the Hall Effect Device once the motors are energized in, respectively, azimuth and elevation and runs to the commanded position. The software and hardware incorporate means for appropriately starting and stopping the motors at a desired point, such as the zero position of a cycle of alternating current to minimize noise; incorporates means for determining when there is a power failure and shutting down the system to prevent damage upon reapplication of power or the like. By this technique, the body is kept correctly oriented throughout the day using only the time of the day without requiring the usual sensors and feedback apparatus.