High stiffness self leveling platform

An adjustable base for positioning a payload structure relative to a surface, the adjustable base comprising:

• a first structure adapted for receiving a payload structure, the first structure having at least three first connecting structures that are radially spaced apart about a center of the first structure;
• a second structure adapted for placement on a surface, the second structure having at least three second connecting structures that are radially spaced apart about a center of the second structure, the first structure and the second structure disposed in an opposing relationship, the second structure having a first portion and a second portion opposite the first portion;
• wherein at least one of the at least three first connecting structures corresponds to at least one of the at least three second connecting structures so as to form a pair of corresponding connecting structures disposed in opposing relationship;
• at least three legs operably interconnecting the first structure to the second structure;
• wherein at least two of the legs comprise electrically powered linear actuators, each having an actuator housing and a rod that extends and retracts linearly relative to the housing when the linear actuator is actuated, the rod defining a rod end of the linear actuator and the housing defining a housing end of the linear actuator, wherein each linear actuator is configured such that the rod does not extend or retract relative to the actuator housing in response to a force applied to the rod;
• wherein each linear actuator is partially interposed between the first structure and the second structure so that the rod end is proximate to one plate structure and the housing end is proximate to the other plate structure, wherein the linear actuator operably connects with one pair of corresponding connecting structures;
• wherein each rod end is configured to connect to the first structure to form a swivel joint permitting rotation relative to the rod about exactly two axes, and wherein each housing end is configured to connect to the second structure to form a rotational joint permitting rotation relative to the housing about exactly one axis and each housing extends through its respective connected rotational joint such that the housing extends from the first portion of the second structure and past the second portion of the second structure;
• wherein each linear actuator can be independently actuated to thereby change at least one of an angular position and a distance of the first structure relative to the second structure, and wherein all linear actuators can be actuated simultaneously whereby the rods of all linear actuators extend simultaneously or retract simultaneously to cause the first plate structure to translate linearly relative to the second plate structure;
• wherein the base is configured such that when the second structure is placed on the surface and the payload structure having a payload weight is placed on the first structure, the second portion of the second structure at least partially contacts the surface and each housing extends at least partially into the surface, the payload structure may be moved to a desired position by actuation of one or more of the linear actuators, and the payload weight is transferred from the first structure to the at least three legs, and then linearly from the at least three legs to the second structure and from the second structure to the surface;
• and
• wherein the second structure and the at least three legs are configured to minimize the bending moment exerted on the second structure from the payload weight when the second structure is placed on the surface.

A powered leveling base for positioning a payload structure relative to a surface, the powered leveling base comprising:

• a first structure adapted for receiving a payload structure, the first structure having at least three first connecting structures that are radially spaced apart about a center of the first structure;
• a second structure adapted for placement on a surface, the second structure having at least three second connecting structures that are radially spaced apart about a center of the second structure, the first structure and the second structure disposed in an opposing relationship, the second structure having a first portion and a second portion opposite the first portion;
• wherein at least one of the at least three first connecting structures corresponds to at least one of the at least three second connecting structures so as to form a pair of corresponding connecting structures disposed in opposing relationship;
• at least three electrically powered linear actuators, each having an actuator housing and a rod associated with the housing, the rod defining a rod end of the linear actuator and the housing defining a housing end of the linear actuator, wherein each rod extends and retracts linearly relative to the respective housing when the linear actuator is actuated, wherein each linear actuator is configured such that it cannot be back driven, and each linear actuator includes a drive member at least partially disposed within its respective housing;
• wherein each linear actuator is partially interposed between the first structure and the second structure so that the rod end is proximate to one structure and the housing end is proximate to the other plate structure, wherein the linear actuator operably connects with one pair of corresponding connecting structures;
• wherein each rod end is configured to connect to one of the at least three first connecting structures to form a swivel joint permitting rotation relative to the rod about exactly two axes;
• wherein each housing end is configured to connect to one of the at least three second connecting structures to form a rotational joint permitting rotation relative to the housing about exactly one axis and each housing extends through its respective connected one of the at least three second connecting structures such that the housing extends from the first portion of the second structure and past the second portion of the second structure;
• wherein each linear actuator can be independently actuated to thereby change at least one of an angular position and a distance of the first structure relative to the second structure, and wherein all linear actuators can be actuated simultaneously whereby the rods of all linear actuators extend simultaneously or retract simultaneously to cause the first plate structure to translate linearly relative to the second plate structure;
• wherein the base is configured such that when the second structure is placed on the surface and the payload structure having a payload weight is placed on the first structure, the second portion of the second structure at least partially contacts the surface and each housing extends at least partially into the surface, the payload structure may be moved to a desired position by actuation of one or more of the linear actuators, and the payload weight is transferred from the first structure to the linear actuators, and then linearly from the linear actuators to the second structure and from the second structure to the surface;
• wherein the second structure and the three second connecting structures are configured to minimize the bending moment exerted on the second structure from the payload weight when the second structure is placed on the surface;
• and
• wherein each respective drive member at least partially is encased in the respective housing portion that extends at least partially into the surface.