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Comment by disago | Hacker News Reader

Sadly, this helicopter won't record any footage, it is only meant to test flight control and to proof that the idea will work for future missions. There is a interesting Veritasium episode (youtube) that talks about this (interviewing the actual designer from the JPL). The only footage will be from Perseverance filming the flight.

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This is not correct, there are multiple downward facing cameras [a]:

1) Navigation (NAV) Camera. This is a global-shutter, nadir pointed grayscale 640 by 480 pixel sensor (Omnivision OV7251) mounted to a Sunny optics module. It has a field-of-view (FOV) of 133 deg (horizontal) by 100 deg (vertical) with an average Instantaneous Field-of-view (IFOV) of 3.6 mRad/pixel, and is capable of acquiring images at 10 frames/sec. Visual features are extracted from the images and tracked from frame to frame to provide a velocity estimate.

2) Return-to-Earth (RTE) Camera. This is a rolling shutter, high-resolution 4208 by 3120 pixel sensor (Sony IMX 214) with a Bayer color filter array mated with an O-film optics module. This camera has a FOV of 47 deg (horizontal) by 47 deg (vertical) with an average IFOV of 0.26 mRad/pixel.

[a]https://trs.jpl.nasa.gov/bitstream/handle/2014/46229/CL%2317...

Shouldn't that be a Return-to-Mars (RTM) Camera?

No, it is going to record images meant to be returned to Earth. See section "Sensors" on page 13 in

https://trs.jpl.nasa.gov/bitstream/handle/2014/46229/CL%2317...

But aren't those cameras just for navigation and won't record or stream any footage?

Edit: spelling

One of the stated goals is to use of the drone to scout interesting places for other drones. In theory I guess it could take that decision without sharing the source images, but that seems a bit far fetched. You'd want to study them in ridiculous detail.

Are you suuuuure about that?

> Its payload is a high resolution downward-looking camera for navigation, landing, and science surveying of the terrain, and a communication system to relay data to the Perseverance rover.

(From Wikipedia)

Also: https://mars.nasa.gov/resources/25526/bottom-of-ingenuity-ma...

I'm pretty sure the point of the helicopter, other than to test powered flight, is to capture frames.

It does have cameras.

https://mars.nasa.gov/resources/25526/bottom-of-ingenuity-ma...

Wow, that’s disappointing. I’m surprised they couldn’t squeeze a basic mobile phone camera module on there just for the sake of it.

The problem isn't the camera, it's the uplink to Perseverance and all the other parts required for a usable camera. They're using Zigbee [1] to communicate with the Rover at 200 kbps and the solar panel recharging the batteries also have to power heaters to keep the electronics alive - there's no hardware connection between the two for data or power exchange AFAICT. The drone is already so heavy that it can only stay aloft for 90 seconds to a few minutes between charges so between the extra battery, lens, better antenna and RF module, etc. it'd require a redesign of the entire mission.

[1] https://rotorcraft.arc.nasa.gov/Publications/files/Balaram_A... - page 15

It's not that heavy, relatively speaking, it has to spin the rotors a lot faster to gain altitude in 1% atmosphere of Earth, hence the shorter flight time.

I suspect it's to save power. Even mobile phone cameras are very power hungry.

I had initially assumed that they would be using it for aerial photos to improve navigation decisions. Kind of sad if not.

There absolutely are cameras on board, and yes they are used for navigation.

My original question relates more to bandwidth, storage and processing limitation which may mean that we won’t see high quality 30 FPS video.

The Snapdragon CPU has plenty of power for JPEG encoding and likely even hardware accelerated encoders. The 640x480 8bpp navcam images could be entirely usable at a fairly lossy 40:1 compression ratio which ends up about about 8KB per frame, for a 90s flight recording at 10fps that's only about 7.2MB to record the whole flight. It would take a little under 5 minutes to send that back to the rover at 200kbps. The color high resolution camera isn't set up for high frame rate recording IIRC so that was never an option.

High quality 30fps video was never really an option but it's entirely possible/likely to get navcam video after a flight. The Snapdragon is also fast enough to do intraframe compression codec (even h.264) for the navcam video to be able to stream it live back to the rover for relaying back to Earth later like was done with the landing imagery.

The nature of Perseverance relaying through orbiters for high speed uplink to Earth was always going to preclude "live" video from any instrument. The only data important enough for "live" transmission is vehicle telemetry and even then that's only available for the portion of a sol (Martian sidereal day) that Earth is visible from the rover.

I think the rover is at least going to film the flight, but agree a camera in it would have been dope.

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