By Mary O’KEEFE
In local elementary schools a common and fun exercise is the egg drop. This is when students are asked to engineer a container that will protect an egg when it is dropped from a high altitude. The experiment is a great family project that has kids using their imagination as they design their protective lander but also teaches them science and engineering.
Well, that basic “what if” principle kids learn in elementary school can be used in the future.
“We have joked about the egg drop experience,” said Lou Giersch, Jet Propulsion Laboratory (JPL) project manager for the Simplified High Impact Energy Landing Device (SHIELD).
JPL is always looking for new and inventive ways of exploring the universe including how to land on the surface of planets.
“The big picture is [that] we are trying to reduce the costs of landing on Mars,” Giersch said.
NASA has touched down on Mars nine times relying on a variety of landings including a crane system in which the spacecraft slowed through the use of parachutes as it approached the surface. A rover was then lowered onto the planet’s surface before the cables were cut and the landing craft flew off. NASA has also used giant balloon type landings, as with the twin rovers Opportunity and Spirit.
Giersch said NASA/JPL have landing systems that work well but they are now looking at how to cut costs of the landings.
“We want to get the cost down [by] 10%,” he said. “A big part of that is simplifying the design.”
So it is looking at an accordion-like collapsible base that acts like the crumple zone of a car and absorbs the energy of a hard impact, according to JPL.
“We are coming in really fast and smacking into the ground,” Giersch said.
A big challenge of the crash landing is the type of surface that will be landed on. Landing areas could range from sandy to rocky to having large patches of ice. So NASA is experimenting landing on steel plates.
“Hitting those big steel plates is our worst case boundaries conditions [which is why] we use these big steel assemblies,” he said.
The team tested the full size prototype of SHIELD’s collapsible attenuator, an inverted pyramid of metal rings that absorb impact.
Team members hung the lander on a grapple and inserted a smart phone, a radio and an accelerometer to simulate the electronics a spacecraft would carry.
Upon opening the prototype and retrieving the simulated electronic payload, the team found the onboard devices, including the smart phone, survived.
Not only would this new design reduce costs but it would also open more opportunity for landing sites.
“We think we could go to more treacherous areas where we wouldn’t want to risk trying to place a billion dollar rover with our current landing systems,” stated Giersch in a NASA/JPL release. “Maybe we could even land several of these at different difficult-to-access locations to build a network.”
The inspiration for this concept actually came from another Mars mission, the
Mars Sample Return. Samples from Mars’ surface have and are being collected on Mars by the current rover Perseverance. Those samples are being placed in metal tubes and will be picked up by a future spacecraft brought back to Earth where they will crash land in a deserted location.
Giersch said while watching these tests the team thought, “If we could do that on Earth, why not Mars?”
And so controlled crash landings may be a thing of the future – not only on Mars but other planets as well.