Improving Accuracy with Quad Inverted Robot Waterjet Cell

by Nino LaDuca, General Manager
Shape Process Automation (formerly Tech-Con Automation) Posted 05/17/2012

Client Saves Cost and Improves Accuracy with Quad Inverted Robot Waterjet Cell
 
Tech-Con Automation helps automotive customer cutting carpets to increase accuracy.
 
Our client is an automotive carpet manufacturer that required a method to cut the carpet into appropriate shapes in a way that was fast, accurate, and reduced waste. Our team combined four (4) MOTOMAN HP-20 robots in an inverted position fitted with UHP hardware to solve the customer’s need.
 
CHALLENGES 

• Operator Interaction: The nature of this product makes it difficult to mechanically convey it into and out of the cell. Operators needed to be able to access the cell to lay and remove carpet, to and from a 3D fixture.
• Speed of Cutting: As a result of operator interaction, the cell needed to reduce cycle time as much as possible where automation is concerned.
• Controlling waste: Cutting cannot damage the carpet. Laser, grinding or alternative thermal cutting methods were likely to damage the product.
• Holding the Carpet in place: Mechanical means of holding the product down could damage the pile and therefore affect carpet quality.

SOLUTIONS

• Inverting the robots: Inverting the robots eliminates the floor-space clutter so that entering operators don’t need to weave their way around the robots to get to the carpet. By inverting the robots, our team could program a ‘safe-position’ to keep the robots out of the way of the operators and deactivated.
• Using four (4) robots working together: The cell cycle time was so short that the length of cut around the perimeter of the carpet was too long to do with one robot. Our team developed a method to run four (4) robots simultaneously without damaging the carpet or interfering with each other. This also resulted in a better quality cut, by slowing down the cutting speed of each robot.
• Waterjet Cutting Tool: Our team chose to use high-pressure water as the cutting tool. This eliminates damage to the carpet and cuts the exact profile without need for tool sharpening.
• Vacuum suction: By developing a suction tank integrated with the cutting fixture, the carpet was held down by negative pressure. Water naturally falls into the tank and excess carpet bits are retrieved the same way by filtering the recirculated water.

BENEFITS

• High-Speed cutting cell: Using four (4) inverted robots cuts down the cycle time to cut one carpet and therefore supports production output quantities.
• No damage to product while cutting: Both holding and cutting the product results in no damage to the product, increasing plant productivity and net shipped product.