RequestTianwen Mars Mission

kuddel

Donator
Donator
Tip: You could (should) use the [ CODE=cpp ]...[ / CODE ] tags for code[*].
They keep the indentation and are therefore much easier to read!

[*] I assume you use the "inline code" [ ICODE ]..[ / ICODE ] tags. Although I might be wrong as I can't see your original "BB code".

Urwumpe

Not funny anymore
Donator
At least we can have a successful landing ensured in Orbiter then, while waiting for the chinese to tell...

Did MRO already pass the landing site?

4throck

Enthusiast !
From another forum ( http://www.unmannedspaceflight.com/index.php?showtopic=8627&view=findpost&p=252358 )

The first communication from Zhurong was only 2 bytes per second, direct to earth.
Now It will use UHF communication and X-band passing through the relay, going to a 2.5 and 6.25 MB of data per day. Thats my understanding from this link on Weibo. So it would be impossible to get an image at the first days. But if they success on using the relay options we will got something soon.
If the information proceeds they have already downloaded less then 200 kB in 3 mars days... Thats why no image...
So,.. Zhurong has not yet used Tianwen-1

This seems correct. They received the first data through Tianwen-1 on Monday:

So they simply lack the infrastructure for efficient communications.
Rover operations will be deeply impacted by this. Again from the same forum ( http://www.unmannedspaceflight.com/index.php?showtopic=8627&view=findpost&p=252362 ):

"Upcoming events
18th May 2021: First images of Mars rover Zhurong will be received as early as 18th May 2021 at 1am UTC (Sol 3). At this time the first data packages will received. But it is not clear if the first data packages have images of the martian surface inside or only telemetry or science data.

22nd May 2021: China’s Mars rover Zhurong will roll down from the descent module to the martian ground (Sol 7).

27th May 2021: China likes selfies. Like the photo sessions of Yutu-1&2 with the Chang’e-3&4 landers on the Moon also Zhurong will do a photo session between rover and the descent module (Sol 13).

28th May 2021: Science program will start on the surface on 28th of May(Sol 14). Zhurong will perform 90 days of science on the Mars. After 90 days they will slow down or stop the mission of the Mars rover. The Tianwen-1 orbiter will change it’s orbit again. The orbiter will enter a science & mapping orbit to inspect and to map the planet Mars."

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4throck

Enthusiast !
First photos: https://mp.weixin.qq.com/s/UCsz3BgAogOpv7qP9fFczQ

As expected, the images are highly compressed.
On the positive side they are using something better than JPG because the macroblocks are smoothed.
And color seems good, judging by the calibration target (on top of the rover, below the antenna).

Very good for a first mission and much better than ESA's Mars rover

gattispilot

Looks like I may need to redo the panels. And make all wheels steerable

gattispilot

redid the rover model. 1 raise the mast 2 antenna, 3 panels.

But now there is a problem. I changed it to 6 wheel steering. So the direction should match the turn angle of the wheels. but something is wrong with that.

Also it the zip is a General vehicle version. just for testing of motion. and sinking
 double sinTurn = sin(2 * PI * TURN_proc); double cosTurn = cos(2 * PI * TURN_proc); if (eAccDir == FORWARD)//MOVING FORWARD { if (TURN_proc == 0) {//wheels are straight so move with heading d_lat = (currentSpeed * oapiGetSimStep() * cos(vs2.surf_hdg) / each_deg); d_lng = (currentSpeed * oapiGetSimStep() * sin(vs2.surf_hdg) / each_deg); } else {//wheels are not straight so move no matter the heading move to the left forward d_lat = (currentSpeed * oapiGetSimStep() * (cosTurn * 1) / each_deg); d_lng = (currentSpeed * oapiGetSimStep() * (sinTurn * 1) / each_deg); } sprintf(oapiDebugString(), "turn %2.2f cos %2.2f sin %2.2f LAT %2.2f LNG %2.2f", TURN_proc, cosTurn, sinTurn, d_lat, d_lng); vs2.surf_lat += d_lat * RAD; vs2.surf_lng += d_lng * RAD; } 

We may need both driving modes. 2 wheel steering or 6 steering.

Might try to redo the aft section

Attachments

• TROVERMARSTEST.zip
1 MB · Views: 3
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gattispilot

I figure out what is wrong. But not sure how to fix it. The wheel steering is not adding the heading. If the Hd is 0 then movement is good.

So the steering needs to be turn angle + heading?

 double sinTurn = sin(2 * PI * TURN_proc+ vs2.surf_hdg); double cosTurn = cos(2 * PI * TURN_proc + vs2.surf_hdg); 

gattispilot

redid the aft dish section

she is able to do 2 wheel steering and 6 wheel steering.

gattispilot

This is what I have so far.
keys 1 raises mast, 2 ant, 3 panels, G switches steering mode.
Ctrl + space open window to operate the mast, aft dish and surface detection

In the formula to determine the springs for touchdown is the MASS. I have it as 240KG. do we know what it should be?

Attachments

• zhurongtest1.zip
1 MB · Views: 3

N_Molson

Donator
Things are going mostly as expected on my side. I should be back in the loop in two or three weeks. Fun fact : tonight I'm sleeping in a motel located next to the quite large CNES complex in Toulouse outskirts. The complex can only be accessed by a long dead end, one time I followed it in car, freshly-painted fences topped by barbedwire and security cameras everywhere. That thing is a citadel, and unless you're completely lost you have no reason to be there

N_Molson

Donator
Just unpacked furniture today, still have to assemble it then fetch my desktop computer 550 km away and other things and I'll be mostly set.

4throck

Enthusiast !
A nice surprise - the rover dropped a camera for selfies:

From https://forum.nasaspaceflight.com/index.php?topic=35045.msg2250692#msg2250692

“着巡合影”图，是火星车行驶至着陆平台南向约10米处，释放安装在车底部的分离相机，之后火星车退至着陆平台附近。分离相机拍摄了火星车移动过程和火星车与着陆平台的合影。图像通过无线信号传送到火星车，再由火星车通过环绕器中继传回地面。

The picture of the "touring group photo" shows the rover traveling to about 10 meters south of the landing platform, releasing the separate camera installed at the bottom of the vehicle, and then retreating to the vicinity of the landing platform. The separate camera took pictures of the movement of the rover and the photo of the rover and the landing platform. The image is transmitted to the rover through wireless signals, and then relayed by the rover to the ground through the orbiter.

So we have something more to simulate!

kuddel

Donator
Donator
Nice portrait - indeed, but what's the science behind that?