New Delhi: Did you know there is a Mars Yard on Earth? At NASA's Jet Propulsion Laboratory (JPL) in Southern California, there is a Martian landscape known as Mars Yard, which is a boulder-strewn mock-up of the real Mars.
OPTIMISM, the twin of NASA's Perseverance Mars rover, arrived at JPL's Mars Yard garage on October 29. OPTIMISM, which has been updated with new features, including additional mobility software and sample caching system, is being used for testing commands before they are sent to Mars, according to NASA.
What Is OPTIMISM?
OPTIMISM is a vehicle system test bed, and a full-scale engineering model of Perseverance. The car-sized rover started a series of tests on JPL's Mars Yard to assess the risk of potential driving hazards on the Martian surface recently in November, NASA said on its website.
OPTIMISM has been dubbed a twin of the Perseverance Rover which is exploring the Jezero Crater on Mars to search for signs of ancient microbial life.
OPTIMISM will perform crucial tasks in the coming weeks, such as navigating the slopes and hazards of Mars Yard, drilling sample cores from boulders, and storing the samples in metal tubes, to mimic the activities of Perseverance rover.
OPTIMISM stands for Operational Perseverance Twin for Integration of Mechanisms and Instruments Sent to Mars.
OPTIMISM rolled out into the Mars Yard for the first time in September 2020.
Why Are Tests Being Conducted?
The tests are important as they will ensure that Perseverance can safely execute the commands sent by mission control on Earth. Also, the unexpected problems which may be encountered by the rover will also be revealed, according to NASA.
Bryan Martin, the flight software and test beds manager at JPL, said they test whether the size and shape of rocks in the visual field will turn into obstacles, and figure out what kinds of things to avoid, NASA mentioned on its website. He added, "What we have safely traversed around here has informed rover drivers planning their traverses on Mars."
The Mars Yard is a huge terrain, and has served as a testing ground for many fully-engineered twins of rovers sent to Mars. The twin of the Sojourner rover which landed on Mars in 1997, the engineering models for the Spirit and Opportunity missions, which started in 2004, and two rover doubles of the Curiosity Rover, which was launched to Mars in 2011, have also been tested on the Mars Yard.
Each rover double has traversed slopes, overcome obstacles, and has helped mission control teams plan new paths on the simulated path of Mars.
JPL has performed tests using the coring drill at the end of OPTIMISM's robotic arm.
Leann Bowen, who is a test bed engineer at Mars Yard, recently tested the performance of OPTIMISM using a computer console, NASA mentioned on its website. During the test, OPTIMISM moved on its six metal wheels and stopped right on the mark on the garage's concrete floor.
The process of drilling core samples from terrestrial rocks in the Mars Yard, and sealing them in metal tubes is a complex task, according to NASA. A variety of rock types are provided to OPTIMISM, due to the uncertainty of the kind of rocks which Perseverance may encounter on Mars.
In one test with the robotic arm, the rover was instructed to park itself on a slope, and then to drill.
Interestingly, OPTIMISM drilled the core successfully. This suggests that Perseverance can also perform drilling on a slope if required, according to NASA.
Jose G. Trujillo-Rojas, the test bed systems engineering lead, said there was a possibility that the rover might slip, and that they wanted to test it on Earth before sending instructions to Perseverance.
What Are The Updates Made On OPTIMISM?
In order to match the features available on Perseverance, some updates have been made on OPTIMISM. The JPL team will also be testing the newly installed Adaptive Caching Assembly for the first time in the Mars Yard. This assembly, which is also present on Perseverance, is responsible for storing rock and sediment samples which will be sent back to Earth by future missions, according to NASA.
Also, OPTIMISM can be used as a platform to figure out the reason behind problems that may arise on Perseverance, and can also provide the solutions to fix them.
Test Drives For OPTIMISM On Mars Yard
Perseverance will have to perform longer drives on Mars in the future. Therefore, Percy's Earth-bound twin will have to be presented with new challenges to test the rover's autonomous navigation system or AutoNav. With the help of a powerful computer, Perseverance makes 3D maps using rover images of the terrain ahead. Also, the rover plans its drive with minimal human assistance using those maps.
The twin rover may pause during Mars Yard tests to think through several possible choices, or to avoid obstacles, NASA stated.
The environmental conditions in which OPTIMISM operates are different from those encountered by Perseverance. The rover on Mars has the ability to withstand freezing temperatures and intense radiation.
OPTIMISM's metal wheels are thicker than its Martian counterparts. This is because the gravity on Earth is stronger than that on Mars.
Also, the deep cold on Mars causes problems for Perseverance. In contrast, the electronics of the OPTIMISM rover are cooled to avoid damage from Southern California's summer temperatures.
Trujillo-Rojas said they try to keep the rover warm on Mars, while on Earth, they were trying to keep the rover cool.
Despite the Covid-19 pandemic posing challenges, a revamped OPTIMISM is ready to get back to work, which Trujillo-Rojas calls a "big milestone", NASA said.