Robots Will Demolish Sears Tower
Robots can detect and disarm bombs or landmines in the name of security. They are dispatched to places humans dare not tread – from the tops of volcanoes to the dark depths of the ocean and the far reaches of the solar system – for the purpose of exploration. They also help with household chores in the name of convenience. But NMU has a novel mission for these mechanical wonders. At 4 p.m. Wednesday, Nov. 16, four robots (including the Trilobot model pictured at right) will be used to implode the Sears Tower in C.B. Hedgcock. It promises to be a speedy yet visually stunning spectacle that will send 15,000 wooden Jenga blocks tumbling to the floor.
For Bryant Varney (AIS), deciding the mode of destruction was almost as challenging as building the tower. He considered several options before contacting Jeff Horn (Mathematics and Computer Science) about the possibility of a programmable assist. The plan is to station a robot at each bottom corner of the structure and connect them to main supports via cables. The robots would ideally pull away with synchronized timing and force, causing the structure to cave in on itself.
“At first I thought coordinating a four-corner strategy would be a bit too ambitious,” Horn said. “I was going to suggest programming a single fast-moving rover to make a run toward the tower, turn in time to side-swipe a corner, and then get out of there fast. But we’re going to go ahead and use four high-torque brutes together because this is Northern – we don’t let anything hold us back, and we’re just crazy enough to try it. Besides, it’s a great learning exercise for my students. What will likely happen is one of the robots will pull the cable taut first, but perhaps not with enough force to knock everything down. This will hopefully give the others a chance to catch up and then together implode the tower.”
“Between now and next week, we’re going to do some testing on a much smaller scale. We’ll also ask the physics department for help measuring the force the robots are pulling with. I can guarantee all four will be there in working order and that they will pull. I just can’t guarantee it will be enough.”
Horn said he plans to assign four heavy-duty robots to the task, including a “juggernaut” model that resembles a monster truck (pictured left). But if the force is not with them come Wednesday, Varney has devised a “Plan B” for demolishing the tower.
“If it doesn’t work out with the robots for whatever reason, we’ll have people standing by to pull the four cables on the count of three,” Varney said. “Either way, it will definitely be a sight to watch it all come down.”
Horn will rely on the assistance of NMU students. Most are in his discrete mathematics course (MA 240); one is in a directed study focusing on robotics.
Varney will collect the Jenga blocks for use on his next project, Big Ben, which he hopes to complete over the Thanksgiving break.