Abstract: A portable coordinate measurement machine having three articulating arm transfer members can provide accurate measurements. The transfer members can be single tube assemblies. The transfer members can each be rotatably joined by relatively short articulating joint assemblies allowing relative rotation of adjacent transfer members about two degrees of freedom. Encoders can be used to measure the relative rotation about each of the degrees of freedom, and signals from the encoders can be digitized by processor boards positioned within the transfer members. Processor boards can be placed in tandem in the transfer members, and one or more of the processor boards can be mounted on a rotatable assembly. Slip rings can electrically couple all of the processor boards to allow for infinite rotatability of the articulating arm.