NASA Getting Ready To Fly A Drone On Mars!

Joined
Nov 17, 2016
Messages
1,077
Reaction score
482
Age
63
Location
Utah, USA
I won't hold my breath that this will work on Mars for more than a few minutes and then what. It looks like it has some solar cells so it should be able to recharge itself but the amount of cells and the distance from the Sun would suggest at most a few watts which for a 100WHr battery would require about 3 days to recharge. The thin atmosphere on Mars has some benefits but also several negatives and lack of lift would be high on that list. Having much larger props might help and/or spinning much faster but it would still be practically limited by the tip speed at less than the speed of sound which on Mars, at the temps typical there, would be about 675mph or 1080kph.

Still, if they can make it work and cover, say, 10km/flight with perhaps 2 flights per week would allow it much greater distance than all the ground based rovers have covered in total in less than a couple months.


Brian
 
  • Like
Reactions: sdileon and Tenisyn
Joined
Aug 17, 2014
Messages
1,355
Reaction score
559
Location
Long Island, NY
I'm sure the brains at NASA will figure it out. The lesser gravity on Mars will be a plus in helping to get it off the ground. Every technology has its baby steps.
 
Joined
Jan 4, 2016
Messages
7,825
Reaction score
3,091
Location
Australia
I won't hold my breath that this will work on Mars for more than a few minutes and then what. It looks like it has some solar cells so it should be able to recharge itself but the amount of cells and the distance from the Sun would suggest at most a few watts which for a 100WHr battery would require about 3 days to recharge. The thin atmosphere on Mars has some benefits but also several negatives and lack of lift would be high on that list. Having much larger props might help and/or spinning much faster but it would still be practically limited by the tip speed at less than the speed of sound which on Mars, at the temps typical there, would be about 675mph or 1080kph.

Still, if they can make it work and cover, say, 10km/flight with perhaps 2 flights per week would allow it much greater distance than all the ground based rovers have covered in total in less than a couple months.


Brian
You don’t have to guess what the flight time might be. It’s detailed in the article.
 
  • Like
Reactions: Tenisyn and sar104
Joined
Mar 19, 2019
Messages
50
Reaction score
19
Age
39
I’m curious how much lift those props will generate in the thin Martian atmosphere.
 
  • Like
Reactions: DroneTurismo
Joined
Mar 19, 2019
Messages
50
Reaction score
19
Age
39
They didn’t get too into the numbers and had a lift assist mechanism.
 
Joined
Mar 19, 2019
Messages
50
Reaction score
19
Age
39
The lift assist was only to replicate the reduced gravitational force on Mars.
That lift assist provided a measure of at the stability on the craft that it won’t have during operations. Will it’s removal have any effect in flight? Who can say for certain?

I just hope they remember to take the lens cover off.
 

sar104

Aut disce aut discede
Premium Pilot
Joined
Mar 22, 2014
Messages
5,128
Reaction score
2,563
Location
Los Alamos, NM.
That lift assist provided a measure of at the stability on the craft that it won’t have during operations. Will it’s removal have any effect in flight? Who can say for certain?

I just hope they remember to take the lens cover off.
Good point about the lens cover. In terms of testing - they only needed to test lift and battery life. Provided that the motors provide enough lift, which they clearly do, and the aircraft can hover, which it clearly can, it will fly. Other flight performance characteristics, such as speed as a function of pitch, can't be measured in earth's gravity, but can be modeled.
 
Joined
Nov 17, 2016
Messages
1,077
Reaction score
482
Age
63
Location
Utah, USA
You don’t have to guess what the flight time might be. It’s detailed in the article.
Well they indicate a desire to test for up to 90 seconds but that hardly details what they expect the true flight time will be. So 90 seconds would seem a floor value but I saw no indication what the expected flight times to be. The cumulative time of 75 minutes is cumulative, not one flight.

Batteries being drained in 90 seconds are not going to last long (lifespan). The distance covered in 90 seconds, when you account for take off and landing, would seem to leave little more than 60 seconds to accelerate, cruise then decelerate giving a range not much more than a ground based rover could expect to cover on Mars in a day and I'd say the expected lifespan will be orders of magnitude shorter. In addition, the range of sensors that can be carried is, well, limited.

I'd argue that a drone is not the best survey tool on Mars.


Brian
 
Joined
Jan 4, 2016
Messages
7,825
Reaction score
3,091
Location
Australia
Well they indicate a desire to test for up to 90 seconds but that hardly details what they expect the true flight time will be. So 90 seconds would seem a floor value but I saw no indication what the expected flight times to be. The cumulative time of 75 minutes is cumulative, not one flight.

Batteries being drained in 90 seconds are not going to last long (lifespan). The distance covered in 90 seconds, when you account for take off and landing, would seem to leave little more than 60 seconds to accelerate, cruise then decelerate giving a range not much more than a ground based rover could expect to cover on Mars in a day and I'd say the expected lifespan will be orders of magnitude shorter. In addition, the range of sensors that can be carried is, well, limited.

I'd argue that a drone is not the best survey tool on Mars.


Brian
Really? The curiosity rover travelled a total of 1km in 12 months. I’d be prepared to bet the drone will travel significantly further in a day with little difficulty. Even in 90 sec.
 
  • Like
Reactions: Tenisyn
Joined
Mar 19, 2019
Messages
50
Reaction score
19
Age
39
Well they indicate a desire to test for up to 90 seconds but that hardly details what they expect the true flight time will be. So 90 seconds would seem a floor value but I saw no indication what the expected flight times to be. The cumulative time of 75 minutes is cumulative, not one flight.

Batteries being drained in 90 seconds are not going to last long (lifespan). The distance covered in 90 seconds, when you account for take off and landing, would seem to leave little more than 60 seconds to accelerate, cruise then decelerate giving a range not much more than a ground based rover could expect to cover on Mars in a day and I'd say the expected lifespan will be orders of magnitude shorter. In addition, the range of sensors that can be carried is, well, limited.

I'd argue that a drone is not the best survey tool on Mars.


Brian
I’ll bet it performs better than any other one we have up there.
 
Joined
Nov 17, 2016
Messages
1,077
Reaction score
482
Age
63
Location
Utah, USA
Really? The curiosity rover travelled a total of 1km in 12 months. I’d be prepared to bet the drone will travel significantly further in a day with little difficulty. Even in 90 sec.

Land based rovers on Mars do not travel very far in a day owing to the fact that the signal delay from Mars to Earth and back is so long they can't control them from Earth -- not real-time anyway. In fact, the cumulative distance traveled by any of the rovers is less than 50km over the entire duration which in some cases is about 15 years. A drone would have some advantages there given they should have less risk of hitting something provided the mission planners review the planned flight and climb high enough to avoid hitting a boulder or hillside. So, even with the limited flight time a drone should indeed be able to cover more territory than a rover. Let's try some guesstimate on numbers here...

If the solar cells can provide 2W, and judging by the size of the panels and the much lower solar flux on Mars, and not counting the dust, and if we put the battery at, say, 40WHrs it would take 2 full days to charge it for a single flight that might cover 200m. So, maybe 100m/day or potentially 36km/year -- this would be much more than the land based rovers manage but we have to account for the limited lifespan of the battery and dust so in reality the total distance covered in its lifespan might wind up being more like 10km.

BUT....

As mentioned before, if the drone actually consumes an appreciable portion of the total charge in 90 seconds or there abouts the lifespan of the batter and therefore the drone will be very short. Also, given the minuscule weight the drone can carry as well as the very limited energy budget, the drone will be very limited in the sensors it can carry. Dust is a problem on Mars and we had a rover die last summer because of it. Every flight will begin and end on loose dirt/regolith -- anyone that's flown a drone knows what that means for dust. If dust reduces the already low energy production from the limited amount of solar cells, and remember some of the energy collected needs to go to keep the batteries and other things warm enough to function -- Mars is like a very northern latitude in the winter and gets real cold.

If the goal is a photo survey then the need for other sensors is reduced, but given the likely short lifespan the amount of ground covered would be no more and likely less than the current rovers. As an exercise to test future tech then I'm 100% OK with this, but as a tool to provide science or even photos I'd argue its viability is, well, not so good...


Brian
 

sar104

Aut disce aut discede
Premium Pilot
Joined
Mar 22, 2014
Messages
5,128
Reaction score
2,563
Location
Los Alamos, NM.
Land based rovers on Mars do not travel very far in a day owing to the fact that the signal delay from Mars to Earth and back is so long they can't control them from Earth -- not real-time anyway. In fact, the cumulative distance traveled by any of the rovers is less than 50km over the entire duration which in some cases is about 15 years. A drone would have some advantages there given they should have less risk of hitting something provided the mission planners review the planned flight and climb high enough to avoid hitting a boulder or hillside. So, even with the limited flight time a drone should indeed be able to cover more territory than a rover. Let's try some guesstimate on numbers here...

If the solar cells can provide 2W, and judging by the size of the panels and the much lower solar flux on Mars, and not counting the dust, and if we put the battery at, say, 40WHrs it would take 2 full days to charge it for a single flight that might cover 200m. So, maybe 100m/day or potentially 36km/year -- this would be much more than the land based rovers manage but we have to account for the limited lifespan of the battery and dust so in reality the total distance covered in its lifespan might wind up being more like 10km.

BUT....

As mentioned before, if the drone actually consumes an appreciable portion of the total charge in 90 seconds or there abouts the lifespan of the batter and therefore the drone will be very short. Also, given the minuscule weight the drone can carry as well as the very limited energy budget, the drone will be very limited in the sensors it can carry. Dust is a problem on Mars and we had a rover die last summer because of it. Every flight will begin and end on loose dirt/regolith -- anyone that's flown a drone knows what that means for dust. If dust reduces the already low energy production from the limited amount of solar cells, and remember some of the energy collected needs to go to keep the batteries and other things warm enough to function -- Mars is like a very northern latitude in the winter and gets real cold.

If the goal is a photo survey then the need for other sensors is reduced, but given the likely short lifespan the amount of ground covered would be no more and likely less than the current rovers. As an exercise to test future tech then I'm 100% OK with this, but as a tool to provide science or even photos I'd argue its viability is, well, not so good...


Brian
They referred to the initial test flights being 90 seconds in duration. I would not expect subsequent programmatic flights to be so short. UAVs operating in earth gravity and atmosphere easily get 20 times that flight time, and there is no physical reason why the power consumption on Mars would be even nearly that much higher, provided that the props are optimized for the 0.02 kg m⁻³ atmospheric density (i.e. 1/50 earth atmospheric density).
 
Last edited:
  • Like
Reactions: With The Birds

New Threads

Forum statistics

Threads
136,126
Messages
1,407,847
Members
99,050
Latest member
UFOcommander