Robotic Material Removal

Nearly all manufacturing processes for metal or plastic products or parts include a material removal process to remove a sharp burr along an edge, grind off excess welding material, or remove a gate on a casting. Done manually, these processes can be labor intensive, hazardous, and costly. Employing a robot to perform material removal has many benefits. Integrating a Robotic Material Removal process, however, can be tricky, and requires an experienced integrator. Because of the many variables inherent in this type of process, robotic material removal is part art and part science. The integrator must balance the cycle time, product quality, and related manufacturing processes, as well as the variability of the robot, parts, and process. Despite the challenges of robotic material removal, it is a proven manufacturing method and growing field. The growth is fueled by lean manufacturing techniques, demanding more from less, and the flexibility of robots in a field known for ergonomic risks, consistency issues and high materials costs.
 
Benefits of Robotic Material Removal

Reduction in costs for metals and energy
Labor savings
Reduction in the number of employees working in a dirty and hazardous environment
Fewer employee repetitive injury claims
Robot replaces humans in a task that is difficult to do manually
Higher quality, more consistent parts or products due to robot repeatability and reliability
More efficient and profitable manufacturing process

MATERIAL REMOVAL PROCESSES
1. Cutting & Trimming  (Saw, blade, water-jet cutting) Robot cuts the perimeter of parts.
2. Surface Finishing & Polishing (buffing, polishing, sanding, grinding, deburring) Robot removes rough edges from a metl part after it is formed, or robot smoothes the finish on metal castings or composites.
3. Plastic edge finishing (de-flashing) Robot cleans up a rough parting line after an injection molding process.
4. Stripping and cleaning – Robot cleans or strips finish from material
5. Drilling & Milling – Robot takes a block of material and creates a shape out of it or drills into it.

 

Considerations before beginning a new Robotic Material Removal Project

Variability of the robot, the part and the process

Robot Repeatability

Part Variability (Sand cast parts have a higher variance than machined parts.)

The amount of space needed for the robot cell, and its relation to other work spaces

Gripper design that will handle part

Robot must be designed for rigors of an environment like grinding

Creating a balance between process quality and cycle time

The robot may need to perform multiple tasks, and the work cell may need to deal with several manufacturing processes.

The process, including the robot and the gripper will need to deal with the changing state of the part

Waste material must be removed

 

New Advances that benefit Robotic Material Removal

  •  Force Control – Tools that detect the force of the media on the part and feed info back to the robot controller to adjust the force.
  •  Vision – Cameras and vision software used to measure the parts’ location relative to the robot
  •  Powerful sensors – Sensors detect the placement of the part in relation to the robot arm and tooling