In a competition pool, engineers tested a prototype of a futuristic mission concept: a swarm of underwater robots that could search for signs of life in the ocean world.
When NASA’s Europa Clipper reaches its destination in 2030, the spacecraft will prepare to aim an array of powerful scientific instruments toward Jupiter’s moon Europa during 49 flybys, exploring the depths beneath the moon’s icy crust. They will be looking for signs that the ocean in the world can support life. The spacecraft, which launched on Oct. 14, carries the most advanced scientific hardware NASA has ever sent to the outer solar system, but the team has already discovered the depths of Europa and other oceanic worlds. The company is developing a next-generation robot concept that has the potential to plunge into deep water. , further advancing science.
This is where the concept of an ocean exploration mission called SWIM comes into play. Standing for Sensing With Independent Micro-swimmers, the project envisions a swarm of dozens of self-propelled cell phone-sized swimming robots. Ice-melting cryobots zoom off in search of chemical and temperature signals that could indicate life.
“Some may wonder why NASA is developing underwater robots for space exploration. It’s because there are places in our solar system where we want to go looking for life, and life needs water. So we need robots that can autonomously explore environments hundreds of millions of miles from home,” said Ethan, SWIM principal investigator at NASA’s Jet Propulsion Laboratory in Southern California. Schaller said.
A series of prototypes of the SWIM concept under development at JPL recently ventured into the waters of a 25-yard (23-meter) competition pool at the California Institute of Technology in Pasadena for testing. The results were encouraging.
The SWIM team’s latest version is a 3D-printed plastic prototype that utilizes low-cost, off-the-shelf motors and electronics. Propelled by two propellers with four flaps for maneuver, the prototype demonstrated controlled maneuvering, the ability to maintain and correct trajectory, and a fore-and-aft “lawnmower” exploration pattern. We managed all of this autonomously, without any direct intervention from our team. The robot even spelled out “JPL.”
The robot was tethered to a fishing line in case it needed to be rescued, and engineers trotted across the pool with a fishing rod during each test. Nearby, a colleague was checking the robot’s movements and sensor data on a laptop. The team completed more than 20 rounds of testing various prototypes in JPL’s pool and two tanks.
“It’s amazing to build a robot from scratch and see it work successfully in the right environment,” Schaller says. “Underwater robots are generally very difficult and this is just the first in a series of designs we will have to undertake in preparation for our journey into the ocean world. It’s proof that we’re able to build robots with capabilities and that we’re beginning to understand the challenges that robots face in underground missions.”
The wedge-shaped prototype used for most pool testing was approximately 16.5 inches (42 centimeters) long and weighed 5 pounds (2.3 kilograms). The robot devised for spaceflight is about three times smaller in dimensions, making it extremely small compared to existing remotely operated and autonomous underwater scientific probes. The palm-sized swimmer will feature miniaturized specialized components and a new wireless underwater acoustic communications system to transmit data and triangulate its location.
Digital versions of these tiny robots underwent their own tests in computer simulations rather than in pools. In the same pressure and gravity environment they would encounter on Europa, a virtual swarm of 5-inch-long robots repeatedly searched for signs of potential life. Computer simulations helped determine the limits of the robot’s ability to collect scientific data in unknown environments and led to the development of algorithms that allow the swarm to explore more efficiently.
The simulation is based on battery life (up to 2 hours), the amount of water that swimmers can explore (approximately 3 million cubic feet, or 86,000 cubic meters), and the number of robots in a single swarm (12, 4 to 5 (transmitted in two waves).
In addition, a team of collaborators from the Georgia Institute of Technology in Atlanta built and tested ocean composition sensors that allow each robot to simultaneously measure temperature, pressure, acidity or alkalinity, conductivity, and chemical composition. Just a few millimeters square, this chip is the first to combine all these sensors into one small package.
Of course, such an advanced concept would require several more years of research in preparation for future missions to the icy moon. In the meantime, Schaller said SWIM robots could be further developed to conduct scientific research at home, such as supporting ocean research or taking important measurements beneath polar ice. I imagine that.
Caltech manages JPL for NASA. JPL’s SWIM project was supported by Phase I and II funding from NASA’s Innovative Advanced Concepts (NIAC) program under NASA’s Space Technology Mission Directorate. The program fosters visionary ideas in space exploration and aerospace by funding early-stage research to evaluate technologies that have the potential to transform future NASA missions. Researchers from the U.S. government, industry, and academia can submit proposals.
melissa pammer
Jet Propulsion Laboratory, Pasadena, California
626-314-4928
melissa.pamer@jpl.nasa.gov
2024-162
