LSU Students Create an Automated Robotic Arm for Crawfish Harvesting

For every pound of delicious Louisiana crawfish, there is a talented and exhausted crawfish farmer whose strenuous, intensive crawfish harvesting labor might soon be aided by a robotic arm designed by students at Louisiana State University, as reported by The Advocate.

When crawfish farmers are harvesting the crop of crustaceans in the summer months, they are oftentimes operating their boat with one foot while leaning over the side, grabbing traps from the waters. Then in an efficiently choreographed, rheumatic motion, they flip the trap at an angle, toss in more bait, and set it back in the water with tactical precision. This method yields 100 million pounds of crawfish every spring, but it is incredibly labor-intensive.

Advocate reporter Caroline Savoie spoke to David Vercher, one of the six LSU biological engineering students who helped to bring an automated crawfish trap-retrieving arm to life. Vercher worked many, many seasons on his family’s farm where they harvested 300,000 pounds of crawfish a day, and he reported that “experienced crawfish farmers get the job done pretty quickly, but it’s hard on their bodies. If they have a device that will make their jobs easier and more sustainable“that makes all the difference.”

Vercher designed, coded, and manufactured the device, which can lift, empty, and re-bait crawfish traps just with a tap of a Playstation 4 controller. The engineering team at the helm of this project are all natives of the state of Louisiana, and they believe that this harvesting arm could save time, money, and potentially prevent back injuries. Funding for the device came from the United States Department of Agriculture.

Tests conducted using the prototype, which is about ⅓ of the size of a commercial crawfish trap, show that it can complete the harvesting task of crawfishing in an average of about 18.3 seconds, which is comparable to a person’s speed.

After she became aware of high costs and labor shortages in the crawfish industry, senior project advisor Professor Chandra Theegala suggested the idea to create the robotic harvester as one of several options for her students’ final assignments. She said of the prototype, “it’s a high-tech project. I originally planned to have a graduate student working on this, but COVID restrictions prohibited that. So I decided to put a team of undergraduates together, and I was extremely impressed with their dedication and interest.” Professor Theegala hopes that the completed project will provide proof of concept to eventually build a harvesting arm to scale.

The project team had worked mostly through Zoom meetings and group messages to delegate the project’s responsibilities according to their enterprises. Vercher has designed the bait reloading device, Ben Thomas programmed and coded the arm’s motion, Damien Glaser constructed the budget and ordered parts, Bryan Tassin conducted background research and managed the team so that everyone was on task, and Sarah Mitchell brought the project to life.

Mitchell accomplished this through the use of her personal 3D printer, which allowed her to produce the harvesting arm’s trap tops, grips, “crawfish,” and “bait” out of PETG plastic, a material that is used in single-use water bottles.

After its completion, the only component of the design that isn’t automatic is aligning the hand with a crawfish trap. This slight incompatibility fuels Thomas’s goal to make the arm entirely automatic so that it can align itself on an actively moving boat. He said that to make his goal a reality, the device would have to also be waterproof, adding, “it would be much quicker. Ideally, the boat would keep moving, and the arm would be able to sense and grab traps at the front of the boat.”

Upon the project’s completion, team member Sarah Mitchell expressed her satisfaction, saying, “I never expected to work on a school project that could make a real difference. It was just our little robot.”

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