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Ingenuity test flight delayed

Due to a software issue identified during testing of the helicopter’s rotary blades, Ingenuity’s engineers have decided to delay its first flight for at least three days.

During a high-speed spin test of the rotors on Friday, the command sequence controlling the test ended early due to a “watchdog” timer expiration. This occurred as it was trying to transition the flight computer from ‘Pre-Flight’ to ‘Flight’ mode. The helicopter is safe and healthy and communicated its full telemetry set to Earth.

They are presently trouble-shooting the issue.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

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"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • Ray Van Dune

    This is why JPL has landed multiple probes on Mars and they have worked. Software engineering discipline and fault-tolerant architecture. Violate them and they bite you, usually fatally.

  • Jeff Wright

    Now an electric motor an a generator are the same right? At end of life…could they park it atop a hill, with winds spinning the blades enough to power go-pro cameras and some instruments,

    Scatter a few “flying windmills on peaks and you have a camera trail.

  • David Eastman

    In theory a motor is a generator and vice versa. In reality, there are all sorts of electronics for timing, regulation, etc that are going to be specific to one case. You can make those complex enough to serve both purposes, but I highly doubt they did so.

  • Doubting Thomas

    Well on submarines you have what are called “motor-generators (MG’s)”. These are effectively AC motors and DC motors coupled together. When the subs reactor is running and turbine generators are running on steam the AC end of the MG runs spinning the DC end as a DC generator which charges the ships emergency battery and runs vital DC powered loads. When the reactor scrams and no steam, the DC end spins the AC end as a AC generator allowing (limited) operation of AC components in the sub for the emergency restart of the reactor.

    So, yes in theory, little Ingenuity could do it. David E is right, for the sub MG’s there is an entire cabinet full of motor regulator, voltage and current regulators and watchdog circuits to make the sub MG function. Oh yeah and the whole smash weighs about 9 tones but I’m guessing that Ingenuity doesn’t need several hundred kilowatts of power.

    But it is a cool idea leaving little camera sentinels along the way.

  • Max

    I remember as a kid that the Volkswagen starter was also the generator. Many cars and trucks use their fly wheel now as the starter and alternator.

    The helicopter is small, so could use solid-state components for the switches to go from series motor to shunt generator. (like regenerative electric vehicles, also called frictionless braking/retarder or regenerative braking)
    The problem is, in a near vacuum, there isn’t enough wind density to drive the blades under a load to create current. More surface area would be required.
    Think of it this way, how large would a wind mill need to be on the moon to catch the solar wind which is always blowing, sometimes 2 million miles an hour?

  • Now I’m all confused about Martian atmospheric density. Some of the links left here are conspiracy-theory-ish, but there is a good point: At the published pressure (near vacuum), neither helicopter flight nor dust devils seem likely and the sky color seems wrong, but planetary scale “near vacuum” is still a LOT of air. On the other hand, the satellite pictures are so clear. On the gripping hand, have you seen Earth satellite pictures, lately? I’ve been looking at real-estate maps and one can easily see how yards are landscaped and sometimes see people, not just cars.

    Suggestion for a photo post: Are there any satellite views of dust storms from the top?

    If there is enough air for lift, it seems that there would be enough air for a windmill – it’s the same thing. If there is enough air to spin dirt around, why would there not be enough air to spin airfoils around? Granted, in order to be a generator, the blades cannot be freely spinning, there will be resistance, but how much can be supported?

    We’ll find out.

  • markedup2 asked, ” Are there any satellite views of dust storms from the top?”

    Tons. When the global dust storm occurred in 2018, most of MRO’s images were useless, blinded by the dust. See this post.

    I should also add that it was that global dust storm that killed Opportunity, as its solar panels couldn’t get enough light to recharge the batteries, and the rover froze.

  • Col Beausabre

    Using DC motors as generators has been operational on straight electric and diesel-electric locomotives since at least the 1920’s. – although Frank Sprague had a primitive form in 1886. Turning the motors into generators makes them act as brakes with the electricity either pumped back into the wires (Regenerative Braking) or sent to on-board resistor banks (think of a giant toaster) where it is dissipated as heat (Dynamic Braking)- on many applications some of the juice from the motors is used to cool the resistors by driving cooling fans

  • john hare

    Enough air to generate loft on a flyweight helicopter is still not very much net energy for a windmill generating power. This thing is barely going to fly for a very short duration because it has to be so light to match the disk loading to vehicle mass. As best I can estimate, the disk loading (blade diameter) on the blades can be no more than 1/15 that of a helicopter on Earth at 18,000 feet altitude.

    It seems to me that a solar cell generating half what it would on Earth is still going to be far more effective than a windmill generating one percent of the power it would on Earth.

  • Mike Borgelt

    NOW they are having software issues? I’d think transitioning to flight mode would be well tested on Earth.

  • Mike Borgelt

    Plenty of nice brushless DC motors in R/C model airplane technology. They are three phase AC but use a small inverter/controller to transform DC from the LiPos to three phase AC. They do work as DC generators if you use a 6 diode three phase bridge rectifier.

  • Lee Stevenson

    This is a fascinating discussion! It reminds of a subject of endless discussion on a ( unfortunately long defunct ) science website I used to frequent. ” Is it possible to make a wind powered vehicle that travels faster than the windspeed? “… The answer seems obvious until you actually do a deep dive into the physics!

  • Max

    Tesla is upgrading the electric motor in their car. Here is an explanation of the improvements and how their electric motor works.

  • wayne

    Interesting video.

  • Lee Stevenson asked ” Is it possible to make a wind powered vehicle that travels faster than the windspeed? “

    On the right tack, top-class racing yachts can exceed the ‘speed of wind’.

  • Jeff Wright

    Zeps in WWI were untouchable for awhile with their engines. The Grob Strato 2 has an oxidizer tank for its propeller engine. Enough air for prop-flight…just not combustion.

    Perhaps later end of life blades can grow wider surface area for power-gen.

    Hoberman could have a go at this and Starship landing legs…he of the hoberman sphere.

  • Lee Stevenson

    Excuse me, I spoke in error, if I recall correctly, ( this was about 15 years ago!) The actual question was would it be possible to build a car like vehicle. The forum was populated with sailors, pilots, scientists of every background, along with amateurs of all the above.. ( of which group I am very much in, so for once I just kept my mouth shut). It was fascinating to see debate on such a technical level. Perhaps some of the residents here are familiar with it? It was called “village of the banned”, set up for users of the infamous “Steorn”s forum banned anyone for questioning their free energy claims. If your not aware of the long running scam that was Steorn, it’s worth a Google. They were convincing, spent a huge amount of money on promotion, and the jury is still out as to whether they thought they had something at the beginning. Anyway, I digress.. can a wind powered car travel faster than the wind?

  • Andi

    Apparently, it can:

    This from that article, gives a good introduction to the concept:

    “You have a robot on an airport style people-mover which moves at 10mph. The robot can use 1 watt to move forward at 2mph on the mover, making a total ground speed of 12mph. To keep this up, it puts out a generator wheel to contact the ground. This wheel sees a total speed of robot_speed + mover_speed. The extra force of this generator rolling along the ground is going to make it harder for the robot to crawl forward, which is going to slow its crawl. What makes this work out is that the generator is using the total_speed, but the robot only needs to produce robot_speed. So they will come to an equilibrium where the robot slows down until the energy its using to move forward is equal to the energy produced by the wheel. Even in a very inefficient setup, the wheel will be producing some power since its moving at at least 10mph, and the robot can use that to make some forward progress.”

    You can even build your own:

  • Star Bird

    If we must send someone into Outer Space lets send Bill Clinton,Barack Obama and Joe Biden

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