Robot arm

Abstract

A portable light weight robot arm assembly similating shoulder, elbow, and wrist movements of a human arm, plus extensions of the upper arm and forearm, accurately positions and holds a power tool for performing driving, drilling, chipping, lifting and the like operations at a work-site. The assembly is self contained having a base easily and quickly mounted on a conventional truck or on the ground at the work-site, a carriage shiftable longitudinally and transversely on the base, an upright pedestal tiltable in all planes relative to the base, an extensible boom or upper arm rotatably and swingably mounted on the pedestal, and an extensible power tool suspension arm or forearm pivoted to the upper arm. Hydraulic jacks control the lowering, raising, and extension of the boom, the tilting of the pedestal, the positioning of the carriage, the extension and positioning of the forearm, and the position of the tool. An hydraulic motor controls the rotation of the pedestal and a hydraulic motor can also operate a winch on the boom. The jacks and motor are selectively activated from a portable station, such as a hand held switch unit, permitting freedom of movement of the operator to best observe the work. The upper arm is swung and tiltable about its shoulder on the pedestal and extended or retracted to position its outer end or elbow. The forearm is suspended on the elbow to position the tool, extended to load the tool, and the tool is held by the wrist end of the forearm in its desired position on the work.