An isolation system is provided that is suitable for use in telephony, medical instrumentation, industrial process control and other applications. An operational amplifier is used that can both source and sink current to simulate the operation of the battery. If the vehicle is an automobile and the interior space is the passenger compartment therein, the first substructure can be the passenger seat and the second substructure can be the A-pillar, in which case, the processor determines the presence or absence of a passenger in the passenger seat. Responsive to selections of editing controls at the palette, documents objects may be added to the canvas. The article is positioned under the frame and the belts are extended to form a sling around the article. The two rails are supported by the top surface and parallel to each other.