The Mars helicopter Ingenuity faced a challenge this week when it lost communications with its rover partner Perseverance, marking the first time in its more than one year of operations that it had missed a communications check-in. Fortunately for the plucky little helicopter, communications have now been re-established. However, it faces an uphill battle with the encroaching Martian dust.
The drop in communications, which occurred on Tuesday, May 3, was due to troublesome dust in the Martian atmosphere, according to an update shared by NASA. With changing seasons on Mars, the amount of dust in the atmosphere is increasing. And this dust can cover up solar panels, like the ones on Ingenuity, rendering them less effective.
NASA’s Mars Perseverance rover acquired this image using its Left Mastcam-Z camera. Mastcam-Z is a pair of cameras located high on the rover’s mast. NASA/JPL-Caltech/ASU
Due to the dusty solar panels, it is harder for Ingenuity to charge its batteries — a problem the helicopter has faced before when a dust storm passed over the Jezero crater where it is exploring, and it had to shake the dust off before it could continue operations. On this occasion, the dust prevented the batteries from charging to such a degree that part of the helicopter’s control system, the field-programmable gate array (FPGA), switched off.
“When the battery pack’s state of charge dropped below a lower limit, the helicopter’s field-programmable gate array (FPGA) was powered down,” explained NASA’s David Agle in the update. “The FPGA manages Ingenuity’s operational state, switching the other avionics elements on and off as needed to maximize power conservation. It also operates the heaters that enable the helicopter to survive frigid Martian nights, maintains precise spacecraft time, and controls when the helicopter is scheduled to wake up for communications sessions with Perseverance.”
The helicopter is designed to turn components on and off during the day and night cycle as they are required. But when the FPGA switched off unexpectedly, it reset Ingenuity’s onboard clock. Then, when the sun rose and sunlight started recharging its batteries again, the helicopter’s time was out of sync with the rover. That meant Ingenuity’s attempts to contact Perseverance were at the wrong time, hence why it missed the check-in.
Perseverance kept listening for Ingenuity’s check-in signal, and it arrived on May 5 at 11:45 a.m. local Mars time. Ingenuity was able to establish a radio link and convey that it was stable, at the right temperature, and its battery was recharging and was up to 41% of capacity.
That’s all good news, but there is an ongoing issue caused by the dust. It will continue to be hard for the helicopter to charge its batteries enough to get through the cold Martian nights. This issue isn’t a surprise, as Ingenuity was originally only designed for five flights but has made an amazing 24 flights so far. With that increased mission length, the team knew that seasonal changes to the weather would create greater challenges.
“We have always known that Martian winter and dust storm season would present new challenges for Ingenuity, specifically colder sols, an increase in atmospheric dust, and more frequent dust storms,” said Ingenuity Team Lead Teddy Tzanetos of NASA’s Jet Propulsion Laboratory. “Every flight and every mile of distance flown beyond our original 30-sol mission has pushed the spacecraft to its limits each and every sol on Mars.”
To try and keep Ingenuity going for as long as possible, the team has sent new commands to the helicopter to lower the temperature at which it turns its heaters on. This saves on battery usage as the heaters consume a lot of power, but it does leave the helicopter’s hardware exposed to cold temperatures, which is risky. However, if the hardware can survive several nights like this, the battery might be recharged enough that the helicopter can fly once again.
“Our top priority is to maintain communications with Ingenuity in the next few sols, but even then, we know that there will be significant challenges ahead,” said Tzanetos. “I could not be prouder of our team’s performance over the last year, let alone our aircraft’s incredible achievements on Mars. We are hopeful that we can accumulate battery charge in order to return to nominal operations and continue our mission into the weeks ahead.”