It’s the 21st-century version of show-and-tell.  

Some Fremont teens are using a robot they have programmed to show fellow students how to toss their trash in a way that’s kind to the environment.    

Working on a team and in competition, the American High School students have spent almost the entire school year tinkering with a machine that separates refuse according to whether it’s compostable, recyclable, or fit for a landfill.  

They’ve put the robot on display in the school cafeteria as well as taken it to elementary campuses, using it as a teaching tool to nip bad habits in the bud.  

 “(Students) will just throw their trash into whatever bin is closest and that can have massive effects on waste cross-contamination,” said 16-year-old Rishabh Athreya, explaining that mixing nonrecyclable items with recyclables interferes with the waste reduction process.  

 The demonstrations also are intended to show younger students how they can apply concepts they’re learning in school to create machines that have practical uses, he said.   

“That’s the reason robots are designed in the first place, to have an effect on the world,” Athreya said.  

The team is participating in a program called FIRST Tech Challenge, sponsored by For Inspiration and Recognition of Science and Technology, a robotics community nonprofit dedicated to inspiring young people to be leaders and innovators in science.

Since previous team members conceived the idea of a mechanical waste sorter four years ago, the automated tool that initially was contained in a small wooden box has become larger and acquired an LCD display.  

A camera captures the image of each object tossed into a container mounted to the outside of the housing. Software recognizes the physical characteristics of items that typically can be recycled or composted and maneuvers the robot’s mechanical arm to drop them in the correct bin.  

Students on the robotics team at American High School in Fremont have developed waste sorters that they have successfully introduced in local and regional robotics tournaments. (Courtesy American High School Ink & Metal 5773 Robotics Team)

If the object doesn’t have those identifying patterns — say, the shiny appearance of something that’s plastic or the relatively smooth texture of a compostable item — the robot deposits it in the trash.   

The digital readout that students added this year displays the name of the bin where an item ends up, thereby reinforcing the lesson of what trash goes where.   

The 15-person team spent a couple of weeks last year “training” the robot to recognize different types of refuse by photographing an estimated 10,000 pieces of trash kids had left lying around campus ranging from milk cartons, juice boxes and plastic water bottles to apple cores and orange peels. They then uploaded the images to a computer along with the correct classification for each.  

The team is using a different robot in competition, one that’s designed to perform on a 12-foot by 12-foot game board and has helped them place both at a city-level and regional championship in San Jose.  

The wins cleared the way for students to showcase their collective brain power next month at an annual international robotics tournament in Houston, Texas.  

Such successes are all the more impressive considering that, unlike nearly every other school-based robotics team, American High School’s teens have learned what they know about robotics on their own, said coach Hardik Naik.  

 “They definitely do learn from each other,” he said, adding that the kids have enlisted the help of mentors like the Lockheed Martin aerospace engineer who meets with them every month or two as well as a former team member who’s now majoring in biomedical engineering at the University of California at Irvine.   

In addition, students have reached out to Amazon, Pacific Gas & Electric Company and Raytheon Technologies Corporation for advice on projects.  

 They also learn from talking with college robotics teams, watching YouTube videos, and referring to the website of the nonprofit that hosts championships.  

 “It was really up to them to learn what they could,” Naik said.  

For about six months of the school year, the students spend at least several hours nearly every day working on the robot they use in competition.  

 Each person focuses on one of five areas that include coding and creating a 3D model of the robot so they can pinpoint any errors in the design before building it.  

Manasa Maddi, 17, joined the group as a sophomore because she enjoys engineering and coding and wanted to learn how to build robots.   

Manasa Maddi says the Ink & Metal robotics group created a high-tech trash sorter to spread awareness about waste mismanagement. (Courtesy Manasa Maddi)  

She soon realized that participation involves a good deal more than wielding drills and wrenches to assemble parts they have created with a 3D printer or ordered from kits.  

The seven girls and eight boys who comprise the team known as Ink & Metal 5773 — the meaning of its name has been lost over time — also organize community events like February’s virtual conference, where robotics teams from 27 countries presented projects they were working on.  

Maddi and her peers also recently uploaded to their YouTube channel a montage of video clips and photos they created from submissions by 121 teams around the globe as a way of inspiring others to embrace the field.  

What’s more, their international outreach has involved creating robotics clubs for high schoolers in Ghana, Dubai and India, and helping them design virtual robots controlled with instructions they have learned to write in Python and Java.  

While other teens are kicking back during the summer break, Ink & Metal uses the downtime to coach new members by having them create their own versions of robots used in previous competitions.  

Not everyone on the team talks about pursuing a career in robotics, however; Maddi has her sights set on becoming a data analyst or software engineer.  

But sophomore Neha Shafi is toying with the idea of working on robots that have applications in medicine, and Aashi Malik, also a sophomore, talks animatedly about plans to continue exploring her fascination with the technology after graduation.  

“Once I joined the robotics (team) it (was) something I can’t leave — it’s become so important to me,” she said. “I really want to be part of the tech industry growth. “(The team) really showed me how robotics has such a big future in the world.”