Quote from: GuessWho on 12/02/2011 11:32 amQuote from: Apollo-phill on 11/30/2011 07:03 pmAnyone have any data for MSL TCM-1 due 10 December 2011 yet ?Rumor has it that MSL entered safemode due to a thruster issue and the first TCM has been pushed back. Anyone here have insight into this?If you read the press release from the beginning till the end, both your questions will be answered.Quote from: kenny008 on 12/02/2011 02:13 pmUMSF reports that the TCM was canceled because of an accurate launch, and the TCM was not needed. The safemode was caused by a star-tracker software issue. They have recovered from safemode, with the exception of the start-tracker problem, which does not appear to be serious.No need to quoted secondary sources. All that information is in the press release if, again, you read it till the end.
Quote from: Apollo-phill on 11/30/2011 07:03 pmAnyone have any data for MSL TCM-1 due 10 December 2011 yet ?Rumor has it that MSL entered safemode due to a thruster issue and the first TCM has been pushed back. Anyone here have insight into this?
Anyone have any data for MSL TCM-1 due 10 December 2011 yet ?
UMSF reports that the TCM was canceled because of an accurate launch, and the TCM was not needed. The safemode was caused by a star-tracker software issue. They have recovered from safemode, with the exception of the start-tracker problem, which does not appear to be serious.
was the velocity sun relative or earth relative?
Could, however, the kick-up of martian regolith during firing of the 'Skycane thrusters' confuse' the altitude attitude sensors perhaps - therefore - releasing MSL too high from ground even if only a few centimtres?
They measure the arc of the transfer trajectory in the sun-relative frame so it makes sense to measure the travelled distance in the same frame.
What drop are you talking about? Look at the EDL sim video. It's basically going to be a constant velocity phase landing similar to what Phoenix executed. The vehicle suspension and wheels are there to provide shock absorption. As Rob Manning said, it should be the smoothest planetary landing to date.
Quote from: ugordan on 12/02/2011 05:25 pmWhat drop are you talking about? Look at the EDL sim video. It's basically going to be a constant velocity phase landing similar to what Phoenix executed. The vehicle suspension and wheels are there to provide shock absorption. As Rob Manning said, it should be the smoothest planetary landing to date.I wondered whether the sensors detecting 'ground surface' could be 'confused' by any dust kickup and thereby releasing the skycrane deployment vehicle before it actually touched hard surface leaving a few centimetres fall .If on flattis ground probably not a problem with - as you say - it has suspension but if on a sloping ground might be more a problem.Are any MSL EDL PDFs around in public domain describing the process in detail ?A-P
Quote from: ugordan on 12/02/2011 05:03 pmThey measure the arc of the transfer trajectory in the sun-relative frame so it makes sense to measure the travelled distance in the same frame. I wonder if I can get accounting to fall for that when I turn my mileage report in.
"........As planned, MSL does not have a direct means of sensing Rover touchdown; a software logic is employed instead.
No, the sensors detect the weight on the bridle which determines landing