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Hi all, It gives me great pleasure to be able to share my rebuild of the Curiosity rover, featuring a highly detailed recreation of the rover itself, the sky-crane-cruise-aeroshell stages, the Centaur upper and of course the Atlas V 541 itself. I spent a great deal of time making sure this looks and operates as accurately as possible. It is a complete rebuild of my older curiosity rover replica but is better in every way! I started by rebuilding the rover itself making use of other parts to get the thin main body of the rover as the parts I was using before where changed in an update. The sky-crane features accurately placed motors and an overall accurate look to the stage. It does feature a probe core of course and an SAS reaction wheel which is disabled by default as the craft is well balanced but for those who want more control authority over the landing and cruise stage can enable it if they like. The real sky-crane had two sets of four motors. All four fired during the first part of the landing and then four shut down during the sky-crane maneuver to avoid contaminating the rover with the exhaust from the motors leaving the four angles ones firing during this stage of the landing. Of course using a cable sky-crane in stock at this scale is not feasible without mods so this replica does not have that. So on my replica during descent one set of four motors fire to slow you down. If you are struggling with the descent you can just stage again which will enable the other four giving you much more thrust. The reason I left four idle during descent was due to my solution for an easy safe release of the rover. What happens is when you are descending keep SAS locked to retrograde (remembering that if you fall below 1 m/s this will disable) When you are a safe altitude to drop the rover, 1m or less you simply press action group 0 which will decouple the port holding the rover to the sky-crane and also activate the other four descent motors giving the sky-crane a boost in thrust to lift it safely and quickly clear of the rover. I do this in the video below. The sky-crane has plenty of fuel for the descent but remember to quick save before any risk mission stages, just in case! We all make mistakes from time to time. The aero-shell has completely changed now and is made from radiators giving it a nice clean all white look like the real aero-shell was. The real curiosity rover had a cruise stage that supplied power to the spacecraft during the cruise stage to Mars. It had a hollow, doughnut shape to it that is very hard to make in KSP. I spent a long time making this, all of the structural panels and solar panels of the cruise stage where placed one at a time! It was time consuming but the results speak for themselves. The look is very close to the look of the real cruise stage. The cruise stage features RSC blocks that are used for adjustments to the orbit during the cruise to Mars and are a very fuel efficient way of making sure you hit your desired EDL altitude. As long as you enter the atmosphere you will be fine. The heat-shield has zero ablator which not only saves weight but is not needed for Duna EDL even at interplanetary transfer speeds. On to the Centaur upper stage. I was not satisfied with the older plain visible tanks look of the old Centaur I made so I made a smooth white body to the stage from multiple fairings which avoids the horrid texture Squad thought was a good idea to apply to the fairings. Inside the fairing are non clipped fuel tanks and power for the Centaur stage. It also features a highly detailed and realistic look to the boat-tail part of the Centaur upper stage. It has correctly placed fuel lines, tanks and supporting structures giving a great sense of immersion that you are flying the real thing. The attitude control thrusters are also correctly placed that are used for maneuvering in orbit and for spinning up the spacecraft before release. The AtlasV 541 now. I chose to make the rocket in colours that make it look like it did at launch, ie, red/orange tanks visible on the lower portion of the craft and the upper part is white. I am not 100 per cent sure why this is. Its either a protective cover on the upper part of the tank or ice formation or a combination of both. I made placed the retro rockets that push the core stage clear of the Centaur upper in the correct place and I decided to recreate the shape of the bottom portion of the rocket. I did this with some more stock procedural fairings. I used the Vector engines, tow of them to stand in for the real Atlas Vs RD-180s they are powerful and have a high degree of gimble giving a lot of control authority over the rocket. The whole thing has almost zero reaction force/SAS! It is flown/controlled by engine gimble and aerodynamics alone. As we all know the stock SRBs are woeful and for heavier payloads you need to use quite a few of them. So for replicas like this and wanting to keep the look of the real rocket you need to make bundles of SRBs. This I did and placed them in the exact 'offset' configuration of the real Atlas V 541! Also they release without any mini SBR rockets! they just fall away into the air stream giving a very realistic look to the SRB separation. OK onto flying the thing. Wait for a Duna encounter window first! You must select the probe core in the top of the Centaur stage before lift off!! So obviously after that the first part is lift off. Before you launch press action group 1 which will deactivate the Centaur RCS and aero-shell RCS. Just press spacebar as usual and off she goes. My rule of thumb for ascents (as I eyeball every single one which I can now do better than any mechjeb type auto pilot mod) is to climb until the speed reaches about 140m/s then start a slow turn to 45 degrees. You want to use little taps of the keys to keep her on track and make sure you don't reach 45 degrees before the speed reaches 500m/s. Then it's a gentle turn over to reach orbit. Stage SRBs when depleted and payload faring when above 35,000m. Press action group 2 to enable the Centaur RCS control thrusters after staging it. The Centaur will complete the initial orbit burn and then circularize when staged and reaching ap. Then burn for Duna. A rough encounter is fine as you will use the cruise stage to fine tune this anyway. The Centaur stage of course is coming with you to Duna so do what they did during the real launch and execute a CCAM (Collision and contamination avoidance maneuver) This just means using the remaining fuel in the Centaur stage to perform a burn that puts the stage into a safe orbit around the sun. Now you will be cruising towards Duna. Sit back and make a cup of tea! Well done for making it this far. To adjust the orbit during the cruise stage you will use the fore and aft thrusters on the cruise stage doughnut. Your keys may differ so have a play on the way to Duna to see how they operate for you. Once you are close to Duna and on the correct flight path for the EDL for the landing site of your choice you can stage the cruise stage with action group 3 this will also active the EDL control thrusters on the aero-shell. You will now be entering the atmosphere, fire! Fear not all will be well. You can then press action group 4 which will stage the chutes but don't worry it will only deploy when safe to do so. When you have slowed a little you can press action group 5 which will stage the heat-shield. Then when you are getting close to the surface press action group 6 which will detach the sky-crane and rover from the aero-shell. Action group 7 will fire up the first four descent motors. Throttle up to max and slow your descent as you fall. You will want to quick-save before this point as it can be tricky to judge. When you are a meter or lower above the surface press action group 0 to detach the sky-crane and activate the second four motors to blast the sky-crane clear of the rover. You should be now sitting safely on the surface of Duna! Celebrate accordingly! Well done for making it this far in this post! During the build I ran into some major issues with the rover wheels. They would break every single time I staged the heat-shield.. I finally managed to fix it by adjusting the suspension settings on the rover. This has led to less than idea handling behavior at higher speeds on the surface so as long as you keep the speed reasonable all should be well. And lets be honest this is not the kind of rover you use for long distance fast travel! It's for landing near a place of interest and exploring locally. And its mainly for the experience of flying the actual mission. Action group quick reference list: 1. Deactivates Centaur and aero-shell RCS 2. Activate Centaur RCS 3. Activate aero-shell EDL RCS and decouple cruise stage 4. Deploy chute 5. Decouple heat-shield 6. Decouple sky-crane and rover from aero-shell 7. Activate descent motors on the sky-crane 0. Decouple rover from sky-crane and fire sky-crane clearance motors NOTE: You can of course when flying, just use the normal staging menu as they are setup correctly. OK enough talk onto the pics and video! I have assembled an Imgur album of course but as well know they cannot be linked here at the moment so I put together a few pics in one to give you a flavor of the craft and if you want to see the pics in more detail you can click on the Imgur link. I also did this for the video (screen grabs) for those who do not have the ability to watch videos online. Full Imgur album: http://imgur.com/a/3iqBf Mission video: Video screen grabs KVV images Spinning gif of the Centaur Upper stage taken in KVV- This was taken of a slightly earlier version of the centaur. It lacks a little of the detail on the boat tail. KerbalX Download: https://kerbalx.com/Majorjim/MJ---Atlas-V-541---Centaur---MSL---Curiosity-rover Thank you all so much for taking the time to look at my post and as always if you have any issues or find and problems please do let me know here. Thanks all! MJ
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