China News Agency, Beijing, January 30th, title: The 100-day life on Earth of the "driver" of the Mars rover at the same frequency as the "Zhurong"
Author Ma Shuisha Guo Chaokai
"In addition to the technical difficulties of driving the Mars rover, there is also a special challenge. It has to work and rest according to the Martian day like the 'Zhu Rong'. International colleagues also face such problems." Talking about the experience of "driving" on Mars, Tianwen Zhang Hui, chief designer of the No. 1 teleoperation mission, said this in an interview with a reporter from China News Agency recently.
Data map: The picture shows the fire surface landform taken by the "Zhu Rong" Mars rover.
Image source: National Space Administration
On May 15, 2021, the "Tianwen-1" probe successfully landed on Mars. When the Beijing Aerospace Flight Control Center received the 8-frame telemetry signal from Mars for the first time, the Mars rover teleoperation team led by Zhang Hui served as the "Zhu Rong" rover. The "pilot" of the "Mars rover" has started working on Mars time on the earth for more than three months.
The Chinese people's first Mars exploration is the first time that Zhang Hui has served as the overall chief designer of teleoperation. Before that, he also participated in the Chang'e 4 mission.
Compared with driving on the moon, operating a Mars rover 400 million kilometers away requires facing new challenges such as unpredictable weather and complex and unknown terrain on Mars.
Zhang Hui and his team prepared for three years to obtain the Mars "driver's license".
In order to learn foreign mission experience, Zhang Hui spent a month studying more than 100 papers in related international fields, and studied until the early hours of the morning almost every day; After working in a confined space covered with volcanic ash for 3 months, I was always "disgraced" at the end of the day.
"When the rover sent back 8 frames of telemetry signals, I knew our team's home field was coming. The rover was fine and the mission was accomplished." Zhang Hui said that this was the most exciting moment in his career. Ready to use.
From the moon to Mars, the increase in space distance has brought great changes to the working mode of the Mars rover teleoperation team.
Zhang Hui said that the time delay of the Earth-Moon system is on the order of seconds, just like driving on the Earth, but it takes about 44 minutes to complete a "question and answer" between Mars and the Earth.
In addition, the lunar rover is visible to the ground scientific research team in real time, but the Mars rover can only see it twice a day.
Due to this periodic communication mode, Zhang Hui and his team must plan in advance the work to be completed by the "Zhurong" in the next Martian day, and then inject the data into the rover, and it will be received during the second communication. The results of the rover's mission execution.
On May 22, 2021, the "Zhu Rong" Mars rover successfully drove to the surface of Mars and began to patrol and detect.
Recalling the experience of the first remote operation of the "Zhu Rong", Zhang Hui said that due to communication reasons, after the order was given to the rover, the ground researchers could not see the real-time situation of the rover, "the waiting process was very tormenting."
He didn't breathe a sigh of relief until the telemetry data came back a day later.
Before dormancy, the "Zhu Rong" had traveled more than 1,900 meters in total.
Zhang Hui revealed that in order to allow the "Zhurong" to move longer distances to explore more complex terrain on Mars, so as to provide scientists with richer and more scientifically valuable Martian data, the team has improved the plan many times.
During the more than three months of the "Zhurong" patrolling Mars, Zhang Hui and the Mars rover were on the same frequency, and spent Mars time on Earth.
A day on Mars is about 40 minutes longer than that on Earth. In order to match the working hours of the Mars rover, the ground team has been dynamically adjusting jet lag for more than three months. Often miss meal spots on earth.
In order to prevent drowsiness at work, mint lozenges have gradually become the standard equipment for team members. "When you are sleepy, take one and wake up instantly."
During the work of "Zhurong", Zhang Hui was not only the driver of the Mars rover, but also a photographer of Mars.
Among the many images of Mars, the "Group Photo on Tour" is a work that Zhang Hui is particularly proud of.
The process of taking this group photo is particularly complicated, not only to consider the lighting and shooting angle, but also to deal with the uncertainty of the Martian terrain.
In order to place the camera stably, ground researchers must find a flat ground.
The rover needs to first drive to the shooting point selected by the ground personnel, release the separation camera installed at the bottom of the vehicle, and then retreat to the vicinity of the landing platform, where the separation camera takes a group photo.
"From releasing the camera, moving back, to taking a group photo, there is only one chance, and the whole process is done in one go." Zhang Hui said, "Netizens named it 'Xinghuo Liaoyuan', and this name is also in line with my inner expectations."
In the next step, Zhang Hui and his team members will also meet the challenge of asteroid detection.
In Zhang Hui's view, from the first lunar exploration, the first Mars exploration to the first asteroid exploration in the future, these "firsts" in China's spaceflight have brought not only the acquisition of first-hand data, the completion of the technical system, but also the accumulation of talents.
"China's space industry has been booming in recent years, providing young people with a stage and opportunities to grow rapidly. China's space industry will go further and further in deep space exploration." (End)