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within 10 minutes and the bandwidth required in communicating hey won’t be marching into a stadium on May 20, but with the lunabot. Alabama Lunabotics will be returning to Kennedy Space To retain their honor, they plan to earn bonus points by Center with the same goal as many other University of Alabama making the robot autonomous — presenting a robot at the students: defending their title as champions. competition capable of navigating across the lunar soil, excavating Last year the team of UA and Shelton State Community at least 10 kilograms and moving back across the soil to deposit College students won the NASA Lunabotics Mining Competition its collection into a bucket without the assistance of an operator. for developing a robot capable of navigating through and This is no easy task considering only three lunabots in excavating 10 kilograms of lunar soil. the 2012 competition had any autonomy at all. Initiating full “UA has consistently been recognized as an innovator,” said autonomy requires the team to create a computer for the lunabot. Dr. Kenneth Ricks, associate professor of electrical and computer They have written software algorithms and included motion engineering and team adviser. “We hope to continue that trend for sensors, laser scanners and cameras on board the lunabot. the 2013 competition.” “Autonomous operation is very difficult and will add They began preparing for the 2012 competition in June significant complexity to the robot,” Ricks said. “Success is 2011 by designing CAD models and obtaining the funding for based upon proper preparation. The the project. Creating the lunabot team must prepare for all aspects of required members to sacrifice most of the competition and have a plan to their time, including winter and spring address any problems that may arise.” breaks. When they couldn’t meet, they And prepare they have. The team worked separately and communicated is divided into groups based on the through email and video chats. subsystems that comprise the robot. “The professionalism of our team The groups meet weekly. These include members combined with diverse the software group that focuses on disciplines made our group resemble the autonomy of the lunabot, the base a business more than a college team,” group that’s in charge of mobility and said Adam Melton, team lead in 2011– the module group responsible for 12. “When the team continued to assist excavation. other teams during the competition — “They had to create initial even teams that posed a threat to our designs, model and simulate these success — it made me very proud to be designs, make modifications based a part of Alabama Lunabotics.” upon simulation feedback, order Though largely studentparts, fabricate the robot, test the governed, Alabama Lunabotics is robot under competition conditions, sponsored by Ricks. The team has —Adam Melton learn to operate the robot, write all participated in the NASA competition the software, design all necessary under his leadership since 2010. He electronics and integrate all parts said the key to their victory rested in together to make a completely functional robot system,” Ricks said an appropriate balance of mass and performance. The team has two potential lunabots to use for the competition. “UA was able to excavate very well while still being one of the The first is called the front-end loader and is significantly lighter. lightest robots in the competition,” Ricks said. “This led to a very Working like a farm tractor, its front-end shovel, decorated with the high score in the mining category of the competition. The other Sharpie-written words “Roll Tide,” is powered into the lunar soil by factor was that the UA team worked very hard to do well in all two actuators that lift and tilt its bucket. categories, while there were some teams that did well at only one The second lunabot, called the bucket-wheel excavator, category. So, this UA team was very balanced and well-rounded.” is much heavier, a drawback for this year’s competition, but is Once again, the team has spent the year preparing for the capable of collecting 100-130 kilograms of soil at once, while the NASA competition, where it will now be judged based on an front-end loader can only collect about 16 kilograms. This lunabot oral presentation, a written systems-engineering paper, project is equipped with small buckets assimilated into two large wheels. outreach in promoting STEM disciplines, team spirit and the Soil collects into those buckets and is dropped onto a conveyor mining category. Within the mining category, the robot will be belt and deposited into an onboard container. judged on its overall weight, the amount of lunar-like soil collected
“The professionalism of our team members combined with diverse disciplines made our group resemble a business more than a college team.”
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{ The University of Alabama }
Top left: The 2012 Alabama Lunabotics take a break from work in space provided for engineering student projects. From left, the team included electrical and computer engineering students Melton and Spryn, along with Justin Baker, student in computer science who was then a student at Shelton State Community College, and Jason Watts, BSEE ’09 and a graduate student. Bottom left: Melton and Spryn work on the lunabot.
“Our advantages last year were that we were light, reliable and robust,” said Justin Headley, lead systems engineer for the team. “That’s what’s going to give us an advantage this year because we are building off the same system.” After completing modifications, the team first tested the functionality of their chosen lunabot in what the students call the sandbox. Few earthly substances are comparable to lunar soil since its top layer is six inches of dry, powdery material, like fresh cake mix, and the layer beneath compacts tightly like concrete. NASA uses a close simulant not commercially available, so the team was responsible for finding its own substitute to use for rehearsal. Their sandbox is filled with dry sand and cement, a material Ricks said is their closest substitute for NASA’s simulant. Next, they tested the lunabot in a volleyball pit on campus. Though the texture of beach sand is not at all like lunar soil, the volleyball pit allows the team to mimic the NASA competition, a 10-minute interval in which the lunabot moves across a 24-feet-long, 12-feet-wide simulated lunar surface. “Our testing is designed to mimic competition situations, including the obstacles, mining, collection and deposition of the
dirt in the bin,” Ricks said. “It is very important for this testing to include practice for the operators. Operator error and inefficiency can lead to lots of problems in the competition. So, it is important that operators get adequate time driving and operating the robot. For each competition run the operators need to carry out a carefully designed plan. So, practice is very important. As an analogy, a slightly slower car with a highly skilled driver can almost always outperform a faster car with a poor driver.” Though Ricks is behind his team every step of the way, he merely serves as a coach, providing technical insight for his students as they design, construct and test their lunabot. “Goals for 2013 are the same as they are every year: to put our best effort into the project so that UA students learn engineering skills, teamwork and what it takes to be successful,” Ricks said. “When UA arrives at the competition, we want our reputation to be one of continued success year after year. While maintaining that competitive edge, team members will represent UA in a first-class manner in all their activities.”
{ Capstone Engineer • Spring 2013 }
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