"We have reestablished reliable communications with Ingenuity," reported the team lead for NASA's Mars helicopter, Teddy Tzanetos,
in a blog post last week.
As detailed in our last blog post, for the first time in our yearlong extended mission we had a loss of communications with Ingenuity from the downlink of May 3 (Sol 427) and May 4 (Sol 428). After a week of anomaly investigation, two sols dedicated to data collection, and the heroic efforts of the Perseverance and Ingenuity operations teams, I am very happy to report that we have reestablished reliable communications with Ingenuity.
Based on all available telemetry, the helicopter appears healthy, and we have resumed a modified form of operations. Assuming winter recommissioning activities complete nominally, Ingenuity's 29th flight may occur in the next few sols.... All telemetry downlinked so far suggests that Ingenuity is healthy, with no signs of damage from the overnight cold cycles.
That's the good news.
The bad news?
Telemetry from Ingenuity confirmed that the loss of communications was due to insufficient battery state-of-charge (SOC) going into the night, which resulted in a reset of our mission clock. This daily state-of-charge deficit is likely to persist for the duration of Martian winter (until September/October).
Challenges like these are to be expected: After hundreds of sols and dozens of flights beyond the five flights originally planned, the solar-powered helicopter is in uncharted terrain. We are now operating far outside our original design limits. Historically, Mars is very challenging for spacecraft (particularly solar-powered spacecraft). Each sol could be Ingenuity's last....
We have reached the point in Martian late fall/early winter at which Ingenuity can no longer support the energy demands of nominal operations. Starting on the evening of Sol 426, we believe Ingenuity started experiencing overnight battery brownouts (drops in the battery's voltage), which reset the electronics. Due to the seasonal decrease in available solar energy, increases in airborne dust density, and the drop in temperatures, the energy demand to keep the electronics powered and warm throughout the night has surpassed Ingenuity's available energy budget.... We expect to be in this challenging winter energy paradigm until around Sol 600, at which point we expect to return to being power-positive from sol to sol.
The blog post says NASA can cope with a resetting mission clock. But the helicopter's battery (and other electronics) are now facing overnight ambient temperatures of about minus 80 degrees C (minus 112 degrees F), "a lifetime risk to our electronic components."
Although component failure has always been a risk that we have carried since rover deployment, that risk is now magnified... We do have limited electronics core module (ECM) component testing to suggest that select components may survive through the winter, but we cannot predict how the entire ECM will fare throughout winter. Cold-soaking electronics is believed to have caused the end of the Opportunity and Spirit Mars rover missions.
Given our elevated risk posture, our focus in the last several sols has been to prioritize data downlink from Ingenuity to the Helicopter Base Station (HBS). We have a handful of Heli-to-HBS transfer activities left before all unique data are copied from Ingenuity to the HBS. Specifically, we are copying flight performance logs, electronics logs, and high-resolution color images from the last eight flights that are still onboard Ingenuity.
After all critical logs are transferred, the team will proceed with a recommissioning phase during which we will reestablish Ingenuity's flight-readiness given our ongoing overnight cold-cycling. Like during the technology demonstration phase, we will perform a high-speed spin before proceeding to flight. Should Ingenuity receive a clean bill of health, we would be ready to execute a short sortie to the southwest in Flight 29. This flight will improve our radio link for approximately the next four to six months while Perseverance samples at the river delta.
In the meantime, the Ingenuity flight software team will be preparing a series of upgrades to enable advanced navigation features. These new capabilities will help Ingenuity ascend the river delta and continue its missions as a forward scout for Perseverance past winter.
Mashable notes that Ingenuity recently sent back
new footage showing its April 8th flight — calling it Ingenuity's "
farthest and fastest flight yet." Flying 33 feet above the surface of Mars on April 8, "it traveled 2,310 feet — a bit less than half a mile — at 12 mph."
The whole record-breaking feat lasted a little over 2.5 minutes, but that's much longer than its first flight of 39 seconds in the spring of 2021. NASA increased the new video's speed fivefold, reducing its runtime to less than 35 seconds.