#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
Hello,

I am practising docking maneuver of the Canadarm with Dragon lately for my school's Science and Maths fair. However, I find it difficult to dock the Arm with Dragon as seen in videos.

In most videos, like those released from SpaceX and NASA, Dragon approaches the Arm and stops at a fixed distance from it. Then, the Arm simply extends in one plane/dimension. that is forward (no rotation, I suppose.) And Capture Is Confirmed. That sounds easy.

But when I try out several times, I find it hard to maintain Dragon at that fixed distance and allow Canadarm to capture it. Any trick or autopilot functions/add-ons that I miss out?

Also, typical Dragon launches from BrianJ's CRS missions that are included in his Falcon9R 1.2 add-on sets the ISS to an orbiting altitude of over 410 km whereas the Falcon 9 autopilot launch altitude target is only some 330 km. (Or maybe it is my computer problem, not BrianJ's fault.) In order to dock with the ISS, I need to raise my orbit by some 60-70 km, which consumes a lot of fuel. I don't think ISS orbits Earth at some 410 km in real world. Then, why my scenario always place ISS at some 410 km? how to rectify it?

I am using the original ISS add-on that comes with the standard Orbiter distribution, not add-ons like ISS 3.2 or ISS AtoZ.

The third problem concerns with the missing Mobile Base System and Special Purpose Dexterous Manipulator on my ISS. This means one end of my Canadarm will be fixed and I can only move the other end freely to capture Dragon. I cannot find any modules or .dll files with the names mentioned above. Am I missing them?

Thanks for your concern over a young inexperienced orbinaut like me.

Regards,

Nicholas.

#### hutchison66

##### Donator
Donator
moving SSRMS

Hi there, are you using Canada arm 4 if you are you can walk it to the bottom of the Destiny Module where it captures the Dragon. its in the instructions how to walk it off.
as for the MBS which ISS are you using? ISS3.2 can move it and ISS A2Z is a space craft you select it then press left Shift Numpad 2 or 8.
hope this helps
David

#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
I am using the original ProjectAlphaISS as supplied by the standard Orbiter distribution zip folder. I don't download any additional add-ons like ISS v3.2 or ISS atoz. The PDGF, MBS and SPDM doesn't exist at all.

Regards,

Nicholas.

#### Nikogori

##### Donator
Donator
I find it hard to maintain Dragon at that fixed distance and allow Canadarm to capture it. Any trick or autopilot functions/add-ons that I miss out?
Pursuit MFD is really useful for docking and berthing. [ame="http://www.orbithangar.com/searchid.php?ID=5866"]PursuitMFD[/ame]

#### boogabooga

##### Bug Crusher
First of all, what happened to Mars aerobraking? I made a playback for you, but then you ignored it.

In most videos, like those released from SpaceX and NASA, Dragon approaches the Arm and stops at a fixed distance from it. Then, the Arm simply extends in one plane/dimension. that is forward (no rotation, I suppose.) And Capture Is Confirmed. That sounds easy.

But when I try out several times, I find it hard to maintain Dragon at that fixed distance and allow Canadarm to capture it. Any trick or autopilot functions/add-ons that I miss out?

Yes.
Try this:
[ame="http://www.orbithangar.com/searchid.php?ID=5866"]PursuitMFD[/ame]

It has a feature that will automatically maintain a fixed distance from a docking port.

Edit: :ninja: by Nikogori.

Also, typical Dragon launches from BrianJ's CRS missions that are included in his Falcon9R 1.2 add-on sets the ISS to an orbiting altitude of over 410 km whereas the Falcon 9 autopilot launch altitude target is only some 330 km. (Or maybe it is my computer problem, not BrianJ's fault.) In order to dock with the ISS, I need to raise my orbit by some 60-70 km, which consumes a lot of fuel. I don't think ISS orbits Earth at some 410 km in real world. Then, why my scenario always place ISS at some 410 km? how to rectify it?

No, all that is about right. The ISS has been orbiting at over 400 km since the space shuttle program ended. Launches of cargo ships are usually to a lower altitude. These orbits are have a shorter period and allow the vehicle to catch up to the ISS. Timing your maneuvers to raise your orbit to intercept and rendezvous with the ISS is a skill and a rite of passage for new Orbinauts. You should have plenty of fuel to raise the orbit. There are many tutorials around for the ISS intercept mission. Try Go Play in Space or David Courtney's Youtube channel.

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#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
First of all thanks to both Nikogori and boogabooga for sharing your Pursuit MFD. I suppose Dragon don't use Pursuit MFD in real-life docking situations. So, how is it that Dragon can dock with the ISS so smoothly without PursuitMFD?

Thanks for telling me about the new ISS orbiting altitude, boogabooga. Regarding your Mars aerobraking video, I had watched it. I can understand what you are doing, keep on spinning and rotating to control altitude of DG. My first trial of aerobraking (and still using it) is simply turning DG 180 degree to create a downward force akin to an inverted aerofoil. I am not familiar with your method of rolling and as this will alter my inclination if I roll too much. Anyway, nice video.

Now, the truth is that in my school's presentation, I will be simulating a real space mission for realistic purposes. I don't really know how old are you, boogabooga. (Maybe you can tell me?) Things in Ohio, the USA are different from things in Penang, Malaysia here. The science atmosphere here isn't "thick." I mean not many people want to learn science for the sake of conducting research. My mission is to let them fall in love with science, especially for high-tech industry like the aerospace sector, which is very well developed in the USA but definitely not in Penang. I need to simulate realistic scenarios before bringing the students into fictional ones. You know, people tend to eager to watch real things, not unfamiliar ones like the DG. i believe they must have seen rockets. So, I reckoned that I should start of with rockets instead of fictional vessels like DG. I love spaceflight, to me starting with either vessels is ok, of course.

Your country already put 2 men on the moon as early as 1969, my country, on the other hand, is lack of money to build rockets even today. Before replying your Mars aerobraking video, I accidentally find out brianJ and Donamy's falcon rocket add-ons. I soon learn to fly real rockets and real missions, including the CRS mission to the ISS. So, I decided to leave aside your video for a while and focus on real ISS missions. I am not familiar with Russian rockets, I therefore don't plan for any Russian Progress unmanned or manned Soyuz mission at the moment. I only focus on CRS mission.

Hopefully you are not angry. I apologizes, boogabooga, for my rather late reply regarding your video. I never ignore them, though.

Yours sincerely,

Nicholas.

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#### PhantomCruiser

##### Wanderer
Moderator
Tutorial Publisher
While the real Dragon may not use PursuitMFD, there is some part of the software suite that is performing much the same function. Since the software is undoubtedly proprietary (and is only good for the Dragon anyway), we might as well use something that does the same function within Orbiter eh?

Sadly, interest in the hard sciences has been falling off in the United States for several decades. It seems that it is far more important to some to discuss celebrety fashions than science and technology. And far too many people will argue that the space program has no value (as they check their facebook page on their smartphone).

One of the many reasons that I am very pleased when I see new Orbinauts here on the forum, even more so to find they are still in school. I certainly wish you well in your quest to spread knowlege to your classmates.

I've never been to Penang, but I've no doubt seen it as I passed through the Malacca Strait on the way to (or from) Singapore (been there 3 times in the late 80's, I loved the place).

#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
While the real Dragon may not use PursuitMFD, there is some part of the software suite that is performing much the same function. Since the software is undoubtedly proprietary (and is only good for the Dragon anyway), we might as well use something that does the same function within Orbiter eh?

Hello PhantomCruiser, I understand that the real Dragon of course doesn't use the PursuitMFD. What I am interested in is how the real Dragon maintains its relative position with the Canadarm when docking maneuvers are carried out. Can you tell me how?

Sadly, interest in the hard sciences has been falling off in the United States for several decades. It seems that it is far more important to some to discuss celebrety fashions than science and technology. And far too many people will argue that the space program has no value (as they check their facebook page on their smartphone).

One of the many reasons that I am very pleased when I see new Orbinauts here on the forum, even more so to find they are still in school. I certainly wish you well in your quest to spread knowlege to your classmates.

Yes, Mr. PhantomCruiser. You are right. My friends prefer phones and fashions to books and spaceflight. That's why I don't have any friends in school, not even one. I can only talk to my teachers in school. They are more matured than my classmates. Also, I decided to take part in forums like here in the Orbiter Forum to meet great masters and mentors like you, Mr. PhantomCruiser. I am always standing beside all space programs. They are valuable. Perhaps in the foreseeable future, when men immigrate to Mars, those who argue that space program will continue to stay on Earth, enjoying the toxic atmosphere and the contaminated sea waters.

I've never been to Penang, but I've no doubt seen it as I passed through the Malacca Strait on the way to (or from) Singapore (been there 3 times in the late 80's, I loved the place).

So, Mr. PhantomCruiser, you saw the small island lurking beneath your airplane window? Actually, I live in the mainland, just opposite the island. I live in Butterworth. You should be able to guess this fact when you know my school name. You should come to Penang, enjoy the food especially, like Fried Kway Teow, Laksa, Nasi Lemak, Hokkien Noodle and tasty cool Cendol. Anyway, I am bored with the above dishes as I used to eat them. But for foreign tourist like Mr.PhantomCruiser, you definitely love it. Beware, they are oily. Eat moderately!

You might not want to explore the Batu Ferringhi beaches anymore. The beach, loacated north of Tanjung Bungah, was once a famous tourist spot, but now the water is contaminated, due to non-civic-minded people's unprincipled actions of littering when they travel across the strait through ferry. The classic vehicle has been an iconic feature of Penang since the colonial British era. Butterworth is very near the harbor, so I used to travel to Penang through ferry. (And I always see people littering on the ferry deck, some would throw rubbish into the sea. These are the ones who will scare future tourist like you, Mr. PhantomCruiser to visit Penang.)

The next time when you visit Penang and travel aboard the ferry. Please help me to scold them. They will be very embarrassed to be scolded by a foreigner and ashamed for their own actions. They won't be afraid of local people like me, a mere 17 year-old teen.

Nicholas.

---------- Post added at 02:22 PM ---------- Previous post was at 01:38 PM ----------

To boogabooga and Nikogori,

I am not familiar with the PursuitMFD. Can you please tell me how to use it. I read the manual and cannot understand the functions. I try using PursuitMFD to dock Dragon with the ISS SSRMSD. However, the Dragon spins wildly when I select APP (the button above HLD) under the DOCKING mode. I don't know when to use HLD, when to use APP. Can both experts tell me?

Regards,

Nicholas.

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#### PhantomCruiser

##### Wanderer
Moderator
Tutorial Publisher
There will be some sort of tracking algorithm that will take station position and Dragon position and utilize the thrusters to return a null value (using doppler, laser/lidar, whatever). Dragon reaches one hold point after another on the way to the station, eventually resting just under it. When the checklists allow, Dragon goes in to "free drift" where there is no more thruster activity and the crew grapple it. That is way oversimplified and there is more to it than that, but it's the overall big picture...

Please, no Mr. Just plain PhantomCruiser will do (or PC, or 'Cruiser). Mr. makes me feel older than I am. I appreciate the token of respect, but it's way too formal (for me) here in the forums. A classroom would be different.

I Never saw the island from above. Only on the surface, I visited the area in 1988, 1989 and 1990 aboard BB-62 (USS New Jersey) and later BB-63 (the World Famous USS Missouri) and I was only a few years older then than you are now. And I certainly do miss the food, it's such a mix of flavors from the region. Yes a little greasy, but oh so good to the taste buds.

#### boogabooga

##### Bug Crusher
If I recall, either Dragon or Cygnus (or both) uses GPS to track its position.

#### Cras

##### Spring of Life!
Donator
The key to Pursuit MFD is you need to set up the target and the right docking port. Then set a distance on each axis that you want to be held at. The MFD will use rcs bursts to get you to that point and then will hold. Pick a point 200 meters or so away on the docking axis, not too hard to figure out which axis that is, null the other offsets out by setting them to zero. Turn on the docking AP which will will activate three things, the distance hold, points you to the docking port, and then orients you in the right direction (that is the white arrow on the docking MFD).

Then when you are holding there, lower your distance offset down either in increments or just go all the way to a few meters out and watch the mfd close the gap. With the docking AP on and you actually want to dock you just set all three distances to zero and watch the MFD bring you in right down the middle of the docking corridor and then actually slow you down for a nice soft contact.

#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
There will be some sort of tracking algorithm that will take station position and Dragon position and utilize the thrusters to return a null value (using doppler, laser/lidar, whatever). Dragon reaches one hold point after another on the way to the station, eventually resting just under it. When the checklists allow, Dragon goes in to "free drift" where there is no more thruster activity and the crew grapple it. That is way oversimplified and there is more to it than that, but it's the overall big picture...

Thanks for sharing. Mentor PhantomCruiser

Please, no Mr. Just plain PhantomCruiser will do (or PC, or 'Cruiser). Mr. makes me feel older than I am. I appreciate the token of respect, but it's way too formal (for me) here in the forums. A classroom would be different.

Ok, I got it Mentor PhantomCruiser. Anyway, I don't understand what do you mean by "a classroom would be different." Are you a teacher? I thought you work in a nuclear plant(based on your forum profile description.)

I Never saw the island from above. Only on the surface, I visited the area in 1988, 1989 and 1990 aboard BB-62 (USS New Jersey) and later BB-63 (the World Famous USS Missouri) and I was only a few years older then than you are now. And I certainly do miss the food, it's such a mix of flavors from the region. Yes a little greasy, but oh so good to the taste buds.

You mean you had set foot on Penang island before? or you simply passed by the island when your battleship cruised across the Malacca strait? South-East Asia cuisine is gastronomical. Based on your reply, I am not very sure if you had tried Penang food. If you do have chance, you should visit the island. The island itself would have lots of tourist attractions to visit. If you enjoy different cultural explorations, Penang is a must-go place.

Nicholas.

---------- Post added at 11:52 AM ---------- Previous post was at 11:51 AM ----------

If I recall, either Dragon or Cygnus (or both) uses GPS to track its position.

I got it. Can you teach me, in detail, how to use Pursuit MFD?

Nicholas.

---------- Post added at 11:56 AM ---------- Previous post was at 11:52 AM ----------

The key to Pursuit MFD is you need to set up the target and the right docking port. Then set a distance on each axis that you want to be held at. The MFD will use rcs bursts to get you to that point and then will hold. Pick a point 200 meters or so away on the docking axis, not too hard to figure out which axis that is, null the other offsets out by setting them to zero. Turn on the docking AP which will will activate three things, the distance hold, points you to the docking port, and then orients you in the right direction (that is the white arrow on the docking MFD).

Then when you are holding there, lower your distance offset down either in increments or just go all the way to a few meters out and watch the mfd close the gap. With the docking AP on and you actually want to dock you just set all three distances to zero and watch the MFD bring you in right down the middle of the docking corridor and then actually slow you down for a nice soft contact.

Hello Cras,

I can roughly figure out what you mean by that. But I need some more specific ways of getting the job done. I mean which buttons should I hit, when to hit that particular button, etc. You know, Cras, I am an idiot. So, I need great master like you to help me (at least tell me which button to push, which configuration page, etc.)

Nicholas.

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#### PhantomCruiser

##### Wanderer
Moderator
Tutorial Publisher
I don't understand what do you mean by "a classroom would be different." Are you a teacher? I thought you work in a nuclear plant(based on your forum profile description.)

I do teach, sort of. I'm a senior instrument mechanic (fancy term for electronic technician that also does some electro-mechanical and electro-hydraulic (old school) stuff). In the strictest sense as a union member it is my job to lead and direct apprentices and journeyman either in a classroom or in the field.

Now I have taught electronics at a community college, plus done some tutoring with algebra and geometry. I may go back to that after I retire here at Watts Bar.

Now for geography ; we only stopped in Singapore, but I had to have seen Penang from the ship. The amount of traffic that transits the straits is astounding. Lots of ships crowded together... we had to pay attention to everything. And anytime we saw a major city, or even a small town all we could thing about was booze (and ladies) that were so close but yet so far away.

My wife wants to visit everywhere that I went while I was in the Navy. Some of those places I never want to take my wife or any "respectable" woman, but I'd certainly go back to Singapore. When I get there, I'll add Penang to the list of things nearby to see. Perhaps a Hong Kong - Bangkok/Pataya - Penang - Singapore trip isn't out of the question?

#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
I do teach, sort of. I'm a senior instrument mechanic (fancy term for electronic technician that also does some electro-mechanical and electro-hydraulic (old school) stuff). In the strictest sense as a union member it is my job to lead and direct apprentices and journeyman either in a classroom or in the field.

Now I have taught electronics at a community college, plus done some tutoring with algebra and geometry. I may go back to that after I retire here at Watts Bar.

Ok, my English is bad, mentor. I know you purposely italicized the word "have." What are you trying to tell me? So, you don't any specialized in nuclear technologies, but you also ventured into electrical engineering and electronics, aerospace engineering and mathematics teaching in schools and educational institutions. You are really great and successful in academia, mentor. (Your salary must be high?)

Now for geography ; we only stopped in Singapore, but I had to have seen Penang from the ship. The amount of traffic that transits the straits is astounding. Lots of ships crowded together... we had to pay attention to everything. And anytime we saw a major city, or even a small town all we could thing about was booze (and ladies) that were so close but yet so far away.

My wife wants to visit everywhere that I went while I was in the Navy. Some of those places I never want to take my wife or any "respectable" woman, but I'd certainly go back to Singapore. When I get there, I'll add Penang to the list of things nearby to see. Perhaps a Hong Kong - Bangkok/Pataya - Penang - Singapore trip isn't out of the question?

So, you must have seen Penang before? But you didn't stop by the port and toured Penang? Malacca strait is very crowded. It was crowded even before the colonial British era. It is the route for connecting the east and the west in the 16-17th century. Nowadays, I hardly see navy ships from the US berth at Penang Port in Butterworth. I think maybe the vessel is too large and the seabed is not deep enough to accommodate these giant beasts. What do you think, mentor?

Yes, nice plan. I think you must be travelling by air then, and no longer by ships.

Nicholas.

#### boogabooga

##### Bug Crusher
Please, no Mr. Just plain PhantomCruiser will do (or PC, or 'Cruiser). Mr. makes me feel older than I am. I appreciate the token of respect, but it's way too formal (for me) here in the forums. A classroom would be different.

Ok, I got it Mentor PhantomCruiser.

:rofl:

Regarding Pursuit MFD...

It's a little complicated. First thing to know is that it was meant to be a replacement for Attitude MFD, with extra content for close proximity operations.

Try to learn Attitude MFD first:
[ame="http://www.orbithangar.com/searchid.php?ID=3165"]Attitude MFD V3.2[/ame]

That should make learning Pursuit MFD easier?

I'll look into it and see what I can do. Too bad that the playbacks don't capture MFD operations...

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#### PhantomCruiser

##### Wanderer
Moderator
Tutorial Publisher
Ok, my English is bad, mentor. I know you purposely italicized the word "have." What are you trying to tell me? So, you don't any specialized in nuclear technologies, but you also ventured into electrical engineering and electronics, aerospace engineering and mathematics teaching in schools and educational institutions. You are really great and successful in academia, mentor. (Your salary must be high?).

You are giving me too much credit (but I am bringing in some pretty good $$). In a nutshell; I spent 10 years in the Navy as an avionics technician (both fixed and rotary wing). Left the Navy and worked for GE as an electronics technician. Left GE for TVA initially to work with combustion turbines, then transitioned to nuclear power. I taught and tutored in between jobs. And part of my job now is to teach when the occasion dictates. There will be an apprentice class forming up in about a year and I will be part of the instructor pool for them, probably be about 20 people with 5 or 6 instructors. That's a 3 year job (to get the class through the program). Teaching the material is easy, meeting all the regulatory requirements is a major pain in the neck. Don't sell yourself short on your English ability. From what I've read so far you write better than many teenagers here in the States. :thumbup: Open invite to any forum members interested, submit a resume to TVA website if you are interested. It'll sit around in limbo until they need to take a look at them, but they can't find it if it isn't there. Now, on to the pursuit of learning about this particular MFD... (see what I did there) Last edited: #### Nicholas Kang ##### Tutorial Publisher Tutorial Publisher News Reporter :rofl: That made my day. Regarding Pursuit MFD... It's a little complicated. First thing to know is that it was meant to be a replacement for Attitude MFD, with extra content for close proximity operations. Try to learn Attitude MFD first: Attitude MFD V3.2 That should make learning Pursuit MFD easier? I'll look into it and see what I can do. Too bad that the playbacks don't capture MFD operations... boogabooga, I don't understand why you laugh until you roll down your bed and just keep on flipping as if they were no frictional force to stop you down. Is it offensive to address PhantomCruiser as Mentor? He said he didn't want to see the word Mr. So, I regard him as my mentor. Is he still angry with me? It is very dangerous in the forum when the moderator hates you. h: Anyway, thanks for your kind help. I will practice hard from now on. Your serious mentee, Nicholas. ---------- Post added at 03:06 PM ---------- Previous post was at 02:57 PM ---------- You are giving me too much credit (but I am bringing in some pretty good$$).

In a nutshell; I spent 10 years in the Navy as an avionics technician (both fixed and rotary wing). Left the Navy and worked for GE as an electronics technician. Left GE for TVA initially to work with combustion turbines, then transitioned to nuclear power.

I taught and tutored in between jobs. And part of my job now is to teach when the occasion dictates. There will be an apprentice class forming up in about a year and I will be part of the instructor pool for them, probably be about 20 people with 5 or 6 instructors. That's a 3 year job (to get the class through the program). Teaching the material is easy, meeting all the regulatory requirements is a major pain in the neck.

Well, mentor, one question please. What do you teach in the apprentice class? Nuclear technology? Or electrical engineering? or spaceflight like Orbiter?

Don't sell yourself short on your English ability. From what I've read so far you write better than many teenagers here in the States. :thumbup:

My English is better than American teens? No, I don't think so, mentor. boogabooga's English is definitely better than me. Don't you agree with me?

Open invite to any forum members interested, submit a resume to TVA website if you are interested. It'll sit around in limbo until they need to take a look at them, but they can't find it if it isn't there.

I hardly see companies that accept resume from the public regardless of age (I am only 17) and nationality (I am a Malaysian, not an American). Are you sure TVA really offer such service? Can you post the link to the application website here?

I will wait for your good news, mentor.

Nicholas.

#### boogabooga

##### Bug Crusher
My English is better than American teens? No, I don't think so, mentor. boogabooga's English is definitely better than me. Don't you agree with me?

I'm not a teen. I'm in my 30s. :tiphat:

#### PhantomCruiser

##### Wanderer
Moderator
Tutorial Publisher
I teach (or will teach again) nuclear power systems and instrumentation.
My sister in law writes in chatspeak. She's 40+ and uses b4 (before), lower case "I", just two examples. So yes, your use of English is pretty good.

#### Nicholas Kang

##### Tutorial Publisher
Tutorial Publisher
News Reporter
I'm not a teen. I'm in my 30s. :tiphat:

Ok, Mentor boogabooga. Since you are not as young as I thought previously. I apologize for any unseriousness in all my previous replies. Please forgive me. And Mentor, I am still waiting for your good news regarding the Pursuit MFD.

Have you found any ways to circumvent the current problem? (Strictly speaking, it is my problem, but I am waiting for your help to show me how to use it.)

Nicholas.

---------- Post added at 12:07 PM ---------- Previous post was at 11:57 AM ----------

I teach (or will teach again) nuclear power systems and instrumentation.
My sister in law writes in chatspeak. She's 40+ and uses b4 (before), lower case "I", just two examples. So yes, your use of English is pretty good.

Ok, I don't want to delve too deep into your personal matters, mentor. I apologize for that. Please don't feel irritated or upset. I shall say sorry in this case.

Regarding your sister-in-law's case, I am not very sure if she only writes in chatspeak when texting through phones (SMS) or Facebook, Twitter, etc. My classmates (NOT my friends) tend to use chatspeak when sending messages to me (through my mother's phone; I don't have a phone, only a computer that runs Orbiter).

However, if she writes using chatspeak during exams or in formal occasions (for instance writing a resume for job application or a letter of complaint), things definitely go bad. I cannot simply judge your sister-in-law's condition based on your (too-short, sorry to say) reply.

Maybe you can clarify, mentor?