System and method for autonomously removing fasteners embedded in wood products

A method for removing fasteners from a recycled wood workpiece comprising:

• receiving the recycled wood workpiece populated with a set of metal fasteners;
• accessing a first internal imaging scan captured by an internal imaging sensor facing the recycled wood workpiece;
• detecting the set of metal fasteners embedded in the recycled wood workpiece based on internal features detected in the first internal imaging scan;
• for each metal fastener in the set of metal fasteners:
• extracting an initial position of the metal fastener from the first internal imaging scan;
• and
• extracting an initial orientation of the metal fastener from the first internal imaging scan;
• generating a virtual model of the recycled wood workpiece based on the first internal imaging scan, the virtual model annotated with initial positions and initial orientations of the set of metal fasteners;
• accessing a first image captured by an optical sensor facing the recycled wood workpiece;
• based on features detected in the first image:
• detecting a first metal fastener in the recycled wood workpiece occupying the work volume;
• and
• deriving a first position and a first orientation of the first metal fastener;
• and
• in response to identifying the first metal fastener analogous to an initial metal fastener, in the set of metal fasteners, in the virtual model:
• isolating the first metal fastener in the virtual model;
• and
• generating a fastener removal schedule defining a tool path for an extractor end effector to extract the first metal fastener from the recycled wood workpiece based on the first position and the first orientation of the first metal fastener stored in the virtual model.

A system for extracting fasteners from a recycled wood workpiece comprising:

• a chassis defining a scan volume and a work volume;
• a conveyor:
• running from an entry of the chassis to an exit of the chassis;
• and
• configured to receive a recycled wood workpiece populated with metal fasteners;
• an X-ray scan module:
• supported by and arranged within a threshold distance of the entry of the chassis;
• and
• comprising an X-ray sensor facing the scan volume;
• an optical sensor facing the work volume;
• a fastener extractor module comprising:
• a stage supported by the chassis;
• and
• an extractor end effector:
• supported and manipulated on the chassis via the stage;
• and
• configured to engage and retain metal fasteners from a section of the recycled wood workpiece occupying the work volume;
• and
• a controller configured to:
• access a series of X-ray scans of the recycled wood workpiece within the scan volume captured by the X-ray sensor;
• compile the series of X-ray scans into a virtual model of the recycled wood workpiece annotated with positions, orientations, and fastener types of metal fasteners extracted from the series of X-ray scans;
• access an image of the work volume captured by the optical sensor;
• based on features detected in the image:
• detect a first metal fastener in the section of the recycled wood workpiece occupying the work volume;
• and
• derive a position and orientation of the first metal fastener;
• map the first metal fastener in the section of the recycled wood workpiece to the virtual model based on the position and orientation of the first metal fastener;
• and
• generate a fastener removal schedule defining a tool path for the extractor end effector to extract the first metal fastener from the section of the recycled wood workpiece.