Helicopter on Mars

[LeftyJason]

That's interesting. Last video I saw of Elon (IIRC), the statement was made that comms took 30 minutes to get back to HQ here if we had a colony - you know, the one-way-trip group that they were looking for. Wonder what the difference is?

Unknown. My dad has been in the deep space communications gig for many moons, so I only know what he's relayed to me from his work.

WTF.........

Elon Musk: radio transmission to Mars take 30 min
SME: it takes 8 min

Conclusion: Elon Musk doesn't understand the topic as well he or you think. He wasn't even fucking close.

Do you understand now?

Elon did a slight exaggeration. Or he is including a round trip time.

Radio travels at the speed of light. What I think everyone is forgetting is that Mars and earth travel in different orbits at different speeds. Distance between changes which makes light travel time different.

Nasa says delay is between 5 to 20 minutes. That would mean a round trip time can range from 10 to 40 minutes.

Communications - NASA

The Mars 2020 rover, Perseverance, has three antennas that serve as both its 'voice' and its 'ears.' They are located on the rover equipment deck (its 'back').

mars.nasa.gov

This shows orbits pretty well.

 

[Maggot]

WTF.........

Elon Musk: radio transmission to Mars take 30 min
SME: it takes 8 min

Conclusion: Elon Musk doesn't understand the topic as well he or you think. He wasn't even fucking close.

Do you understand now?

Seems there is some debate on that, and some variables affecting the answer.

1. How far away is Mars from the Earth in light minutes? - Quora​

   www.quora.com/How-far-away-is-Mars-from-the...
   The distance of Mars from Earth varies while they are orbiting Sun.The shortest distance is 34.6 million miles when Mars is 3.09 light minutes away and longest distance is 250 million miles when Mars is 22.36 light minutes away.On average Mars is 12.72 light minutes away.Two way telephone communication time from Mars to earth on their shortest distance is 6.18 minutes and on their longest distance is 44.72 minutes.

2. NASA movies show how fast light travels from Earth to the ...​

   www.businessinsider.com/how-fast-speed-light...
   That's six minutes and four seconds for a light-speed round-trip. But on average, Mars is about 158 million miles from Earth — so the average round-trip communication takes about 28 minutes and 12...
   • Author: Dave Mosher

3. Time delay between Mars and Earth – Mars Express​

   blogs.esa.int/.../time-delay-between-mars-and-earth
   Aug 05, 2012 · Mars is so far away in fact that it takes radio signals quite a long time to get from the spacecraft back to Earth. During Curiosity EDL, this delay will be 13 minutes, 48 seconds, about mid-way between the minimum delay of around 4 minutes and the maximum of around 24 minutes.

 

[Davo308]

That makes sense. The big issue is with the 1.5 minutes of flight time would be the amount of time it takes the batteries to recharge vs the amount of time the rover would take to make up that ground. If the rover can move faster than the recharge time you would have a situation where the rover would be leaving the helo behind and then the helo would spend a certain amount of time catching back up to the rover before it can resume recon. I'm sure that this has been thought through. I never saw on the video where it mentioned the speed of the drone. Someone mentioned that the helo was to gather intel, send it back to the rover, back up to a satellite and then to NASA, which probably means they are gathering info and then directing movement for the rover based on what they see. Lots of ways to do it. Did they mention it docking on the rover during recharge? That would be a good way to go - fly, gather info, return home on the rover, recharge, do it again. That way movement stays matched between the vehicles.

The rover itself has a non solar internal source of energy, maybe nuclear. Thats what I read back when it was launched from earth. The drone has solar for recharges and actually uses much of its power not for flight or video but to keep the electronics warm. It also has a co2 insulation layer.

 

[Davo308]

8 minutes "light time" (speed of light) for time of transmission to reception. So, data transmitted from here to there takes 8 minutes, and visa versa. *Shooting a bullet from a moving platform to a moving target with an 8 minute time of flight*.

In order to capture the signal in time with the rotation of the earth and whatnot, there are 3 locations where the signals can be sent ad received from eart: 120 degrees apart for 24 hour coverage. Those locations are the NASA Goldstone facilities located within Ft. Irwin, CA, in Canberra, Australia, and Madrid, Spain. These facilities have been in operation since the beginning (Mercury and Gemini) space missions, because fuck the CCCP.

Radio stations on earth typically push out 50 kilo watt (50kw or 50,000 watt) signals on the FM frequencies. The signals pushed out of the NASA DSN (Deep Space Network) go beyond 50,000kw and sometimes into the 100,000kw. The microwave signals are so powerful you could pass a 1/2" Steel ball bearing through the signal beam and the ball bearing will be vaporized after a quick flash. The cooling systems for these high powered transmitters use liquid helium keep them within operating temperatures to not melt components.

If you wanna go down a rabbit hole, look up a "low-noise amplifier" and see how they "listen" to the sounds coming from the radio frequencies received from outer space. Cooling down a vacuum to near "absolute zero" to interpret molecular movement as the radio transmissions are received. It's a trip.

Did not know Irwin had NASA facilties.

 

[TheHorta]

Mars is Republican.

Red Planet, bitches!

 

[Dogtown]

Quantum-based communications will change things dramatically

You can’t transmit information faster than the Speed of Light because luminal speed is actually the Speed of Causality. The quantum communication idea people often erroneously bring up relates to entangled particles being able to transmit super-luminal information. This is because if you have two entangled particles, separate them by some distance, then measure the spin of one. Doing so instantaneously tells you the spin of the other. So cool, why not make a commo device using entangled particles so you can have instantaneous comms between planets (using spin as binary code)?

The problem is that this is a misunderstanding of entanglement. A better analogy is to imagine having a pair of gloves that are quantum entangled some how. You send one to Mars in a box and then open the box at some point and see that it’s a right hand glove. Now you instantly know that the glove on Earth is left handed. It’s not really information transmitting.

That‘s a more correct explanation, although I’ll be the first to admit I struggled in my Quantum Mechanics courses (General Relativity and Fluid Mechanics was more of my focus) so I by no means have a deep understanding of the subject.

 

[lariat]

The rover itself has a non solar internal source of energy, maybe nuclear. Thats what I read back when it was launched from earth. The drone has solar for recharges and actually uses much of its power not for flight or video but to keep the electronics warm. It also has a co2 insulation layer.

The CO2 layer is seriously cool. One of the biggest problems we have seen with drones in the arctic and similar environments is battery performance, which leads to internal heaters for the batteries and/or a way to capture the heat from the electronics, but this is while the drone is active.

One thing about batteries is that the power supply is not infinite; add in a camera and other accoutrements and you will see flight time dwindle, sometimes quickly depending on the attachment. While flight time is important it can become a "secondary consideration of primary importance", which is what it appears has happened with the NASA helo in order to keep it operational. Serious props to them for figuring it out. Some end users want an autonomous swiss army knife and we have to work through actual missions that they will use them on (or past missions they would have used them on) and actual tactics in order to determine what the need is, simply because the battery technology is not there yet to give high power reserves with light weight, although its getting there. Its why I brought it up previously regarding the actual purpose of the helo. Thanks to you guys who gave info that made that clearer.

 

[Davo308]

The CO2 layer is seriously cool. One of the biggest problems we have seen with drones in the arctic and similar environments is battery performance, which leads to internal heaters for the batteries and/or a way to capture the heat from the electronics, but this is while the drone is active.

One thing about batteries is that the power supply is not infinite; add in a camera and other accoutrements and you will see flight time dwindle, sometimes quickly depending on the attachment. While flight time is important it can become a "secondary consideration of primary importance", which is what it appears has happened with the NASA helo in order to keep it operational. Serious props to them for figuring it out. Some end users want an autonomous swiss army knife and we have to work through actual missions that they will use them on (or past missions they would have used them on) and actual tactics in order to determine what the need is, simply because the battery technology is not there yet to give high power reserves with light weight, although its getting there. Its why I brought it up previously regarding the actual purpose of the helo. Thanks to you guys who gave info that made that clearer.

Yeah the vid I saw from the drone chief engineer said it had like 10 to 20 minutes of flight time a day, and could be fully recharged by the next day. Optimum flight time was 11 am, while the martian winds were low and sun was high overhead for camera work.

The kind of checklist they have to go through, from getting it deployed (its currently under the bottom of the rover, which will blow small explosive bolts to set it in the right position, then move off of it), to its initial use is fascinating.

Small bits of pre.coded instructions, lots of documentation and coordinating with the rover.

 

[lariat]

I need to do some research into what type of battery they are using. That many flights means that the battery is never idle - it’s being constantly pulled down, even while recharging (I assume if it is needed for warming). That’s crazy. Not the plan for a long life of such a small battery unless I’m missing something. The load on that battery has to be pretty well defined for a Martian day, like by the minute.

 

[BullGear]

Here's the NASA link for the copter. Doesn't seem like the juice is worth the squeeze to me.

Mars Helicopter - NASA Mars

 

[lariat]

Here's the NASA link for the copter. Doesn't seem like the juice is worth the squeeze to me.

Mars Helicopter - NASA Mars

Cool, yes. But a 4 flight goal seems low unless they are not confident in the equipment or inside of the conditions, which ultimately is still the equipment.

Not knocking the JPL or NASA team but that seems a bit low of a bar to claim success. Hopefully they gat a shit ton of data out of it to use as a baseline for future developments.

All that being said I would love to have something up there. And then fly it to complete burn-out failure. That’s how you learn.

 

[BullGear]

Cool, yes. But a 4 flight goal seems low unless they are not confident in the equipment or inside of the conditions, which ultimately is still the equipment.

Not knocking the JPL or NASA team but that seems a bit low of a bar to claim success. Hopefully they gat a shit ton of data out of it to use as a baseline for future developments.

All that being said I would love to have something up there. And then fly it to complete burn-out failure. That’s how you learn.

I agree, but I'm sure they had to calculate the added weight for the flight to Mars. It would seem to be a large compromise.

 

[LeftyJason]

Here's the NASA link for the copter. Doesn't seem like the juice is worth the squeeze to me.

Mars Helicopter - NASA Mars

Stated under main job. It's a technology demonstrator. That's what it's for. If it works they will likely use it for years til it breaks. Spirit was planned for 90 days and lasted 1944 mobile. Opportunity was 90 days and lasted 15 years. Curiosity was planned for 2 years and has been going over 8 years.

 

[clcustom1911]

Cool, yes. But a 4 flight goal seems low unless they are not confident in the equipment or inside of the conditions, which ultimately is still the equipment.

Not knocking the JPL or NASA team but that seems a bit low of a bar to claim success. Hopefully they gat a shit ton of data out of it to use as a baseline for future developments.

All that being said I would love to have something up there. And then fly it to complete burn-out failure. That’s how you learn.

Well, this is the first of it's kind in history. So, if you feel you can do better, go ahead and drop that résumé and show them how it's done.

I assume the first time you ever picked up a bolt gun you were shooting 1000y in variable crosswinds and getting first round hits with no DOPE?

 

[lariat]

Well, this is the first of it's kind in history. So, if you feel you can do better, go ahead and drop that résumé and show them how it's done.

I assume the first time you ever picked up a bolt gun you were shooting 1000y in variable crosswinds and getting first round hits with no DOPE?

Nope. Kind of sucked at it actually. If you read the entirety of this thread I am giving them a pretty big thumbs up for the design. Its odd however that they could do 10-20 flights a day but call 4 flights a success in reaching their goal. Seems low for the stated capability for some reason. No idea why they decided on 4 and I haven’t found anything that states why. Maybe that’s the life limit of some of the COTS equipment on board? Who knows.

 

[BullGear]

I would consider a 50% prospect to be a conservative number. I don't know why the very low number but there's a reason for it. Maybe they know that Marvin will be able to vector it's flights if any more are done. Marvin can be a really good shot with that ray gun of his.

 

[Davo308]

Cool, yes. But a 4 flight goal seems low unless they are not confident in the equipment or inside of the conditions, which ultimately is still the equipment.

Not knocking the JPL or NASA team but that seems a bit low of a bar to claim success. Hopefully they gat a shit ton of data out of it to use as a baseline for future developments.

All that being said I would love to have something up there. And then fly it to complete burn-out failure. That’s how you learn.

Its a first of its kind, they are going to be conservative. I bet it comes in handy for all of the reasons they are handy on earth and then some.

There have been atmospheric balloons released in the past by the USSR.

This tech wouldnt work on the moon because of its nearly non existant atmosphere.