An upper torso garment, such as a jacket, can be folded within itself to transform it into a different shape for use as a pillow. The main characteristic of the present invention lies in the machine having means for detecting a correct posture of the user and which are fitted to the supporting surface. A second method is to fix definite periods ahead of time for performing ranging, then cluster the multiple periodic transmit signals together in sets at the transmitter and send them, and then disassemble those sets back into signals at the receiver. The body portion may include a face portion, a toe portion, a sole portion, an interior cavity that may extend between the top and sole portions, and a back portion with a plurality of exterior weight ports having a first set of exterior weight ports and a second set of exterior weight ports. A computer implemented method for a handheld computer system for determining spatial orientation is also disclosed. The port replicator thus constructed is simple to fabricate and assemble, and is adaptable to notebook computers of varying thickness to provide a steady and secure coupling.