Building construction apparatus

A spot welding system, comprising:

• a rover vehicle comprising at least one movable arm and rover drive hardware configured to transport the rover vehicle over an upper corrugated sheet of metal;
• a crawler configured to travel under a lower corrugated sheet of metal beneath the upper corrugated sheet of metal, the crawler provided with crawler drive hardware and a movable electrode provided with electrode raising/lowering hardware configured to raise the movable electrode to a weld point;
• and
• a central power/data unit connected to the rover vehicle and crawler;
• wherein the rover vehicle is configured to position one movable arm above the upper corrugated sheet of metal and effectuate a welding function proximate the weld point.

A building construction spot welding apparatus, comprising:

• a rover comprising at least one movable arm and rover drive hardware configured to transport the rover vehicle over an upper corrugated sheet of metal;
• a crawler comprising crawler drive hardware configured to propel the crawler under a lower corrugated sheet of metal beneath the upper corrugated sheet of metal, the crawler provided a movable electrode provided with electrode raising/lowering hardware configured to raise the movable electrode toward the lower corrugated sheet of metal and toward a weld point;
• and
• a central power/data unit connected to the rover and crawler and configured to coordinate positioning between the rover, the crawler, and the weld point;
• wherein the rover is configured to position one movable arm above the upper corrugated sheet of metal and effectuate a welding function proximate the weld point.