Obstruction detection device

A truss fabrication system comprising:

• a truss assembly table having a first side rail, a second side rail, and at least one accessway;
• a gantry press mounted on the truss assembly table for movement relative to the truss assembly table;
• a first obstruction detection device being mounted on the gantry press;
• a second obstruction detection device mounted on the gantry press opposite the first obstruction detection device, each of the first and second obstruction detection devices comprising:
• a support structure attached to the gantry press for movement with the gantry press along the truss assembly table;
• an obstruction sensor connected to the support structure and configured to detect obstructions in the at least one accessway of the table, the obstruction sensor having an activated state and a deactivated state;
• and
• a control system operatively connected to the obstruction sensor for activating and deactivating the obstruction sensor in response to a position of the obstruction sensor relative to the at least one accessway, wherein the control system activates the obstruction sensor when the obstruction sensor is aligned with the at least one accessway of the truss assembly table so that the obstruction sensor can detect obstruction in the spaced accessway, and wherein the control system deactivates the obstruction sensor when the obstruction sensor is out of alignment with the at least one accessway of the truss assembly table to prevent the obstruction sensor from stopping the gantry press of the truss fabrication system;
• and
• the control system further comprising a controller configured to stop movement of the gantry press along the truss assembly table when an obstruction is detected in the at least one accessway of the truss assembly table by the obstruction sensor.