The Mars Helicopter Is Online and Getting Ready to Fly

Post by ddingus » Sun, Feb 28, 2021, 6:22 PM UTC

Robotbeat wrote: post #51

marcinzm wrote: post #37

Earlier quoted context omitted.

As the name RAD750 indicates, that processor is designed to be radiation hardened which matters for longer missions. I doubt the Snapdragon 801 will survive as long or have as few errors but it also doesn't matter since Ingenuity isn't aimed for long term usage.

It’s less about longevity and more about reducing errors. Interestingly, Ingenuity has some sort of watchdog that can reset the Snapdragon in-flight fast enough to recover if there is an error.

Post by tjoff » Sun, Feb 28, 2021, 6:23 PM UTC

disago wrote: post #57

l2p wrote: post #35

Earlier quoted context omitted.

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/se…

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

Post by Robotbeat » Sun, Feb 28, 2021, 6:24 PM UTC

Youden wrote: post #46

Does anyone know why they chose to send a helicopter and not some kind of plane or glider? I would've thought that a fixed-wing aircraft would have been simpler, lighter, faster and more efficient.

Post by jjoonathan » Sun, Feb 28, 2021, 6:24 PM UTC

Robotbeat wrote: post #51

marcinzm wrote: post #37

Earlier quoted context omitted.

As the name RAD750 indicates, that processor is designed to be radiation hardened which matters for longer missions. I doubt the Snapdragon 801 will survive as long or have as few errors but it also doesn't matter since Ingenuity isn't aimed for long term usage.

It’s less about longevity and more about reducing errors. Interestingly, Ingenuity has some sort of watchdog that can reset the Snapdragon in-flight fast enough to recover if there is an error.

Post by londons_explore » Sun, Feb 28, 2021, 6:30 PM UTC

jessriedel wrote: post #67

Robotbeat wrote: post #50

Earlier quoted context omitted.

They work better primarily because they had previously invested in the tooling to rad-harden them and it’s really expensive to do that again one time for each mission; cheaper to rely on already-rad-hardened designs.

Doesn't radiation mostly cause random one-off errors rather than permanent defects? If so, then if the rad-harden stuff is 100x slower (which I think is approximately right?), it is almost certainly better to use error correction on non-rad-hardened hardware.