V2 by igel

Ver. 1.0

Build: 3 Nov 2006

Andrew Thielmann aka igel

atil@pin-plus.ca

Contents

1. Quick list of custom controls.

2. Why "yet another V2 addon"?

3. What is in the focus of this particular V2 addon?

4. What is NOT in the focus?

5. Pre-empt on "militarization" rants

6. Credits.

1. Quick list of custom controls.

Keys

+ key | launch currently focused V2, or restart the main engine in-flight.
- key | shutdown the main engine of currently focused V2.
O key | launch all V2s in scenario. Or, more accurately, send them a signal for the launch. The actual ignition of each individual V2 may be delayed by the number specified in the LAUNCHDELAY scenario variable. By default, there is no delay.
A key | toggle autopilot. No visual indication is given on the autopilot state. By default, autopilot is ON.

Custom Scenario variables

RANGE, meters | - programmed range. Heading is governed by Orbiter, V2 does not perform roll maneuver after launch.
LAUNCHDELAY, seconds | - the launch is delayed by this number if a launch signal is obtained externally, via 'O' key. The discrepancy in launch timing gives mass launches more realistic look.
REALISTIC, 0 or 1 | - flag for realistic vs. ideal mode. The modes differ in guidance system implementation, accuracy and reliability. Default is 1 (on).
LATITUDE_TARGET, degrees | - helpful for flight analysis, especially with advanced targeting techniques.
LONGITUDE_TARGET, degrees | - same as above.
TARGET, string | - target name, useful for flight analysis of scenarios with multiple V2s and targets.
AUTOPILOT, 0 or 1 | - default is 1 (on).
RELIABILITY, % | - reverse of the probability of an onboard system failure. Default is 75% for realistic mode and 100% for ideal mode, can be overridden for both.

2. Why "yet another V2 addon"?

Being a very simple rocket, V2 is an ideal tool for trying new things, features, approaches and ideas in Orbiter. Save development time by inheriting from the existing addons. "Borrow" features you like. Add new stuff without bothering about backward compatibility. It is so easy to keep the code base small and compact - simply remove any stuff you consider irrelevant for your context! Finally, when things look good, roll out a separate addon without overwriting any of the precursors.

This way, the new features can be published and field-tested faster - which can improve their chances to go mainstream via the "natural selection" process. Even if every single Orbiter developer creates his own "pet" V2 addon, Orbiter can easily accommodate them all.

Another big advantage of V2 - it world fame. V2 history is so long, so remarkable, so controversial, it had spanned so many years, and left memories and material evidence in so many countries around the globe - that no single modern rocket or space program can match! It is simply impossible to learn rocketry without running into V2 over and over. So, even after so many years, quite a lot of people can _personally_ relate themselves to this historical Vehicle. Simply speaking - I expect this addon to be interesting to enough people to justify it making.

3. What is the focus of this particular V2 addon?

User experience

From the user's perspective, the focus is on the whole end-to-end mission simulation. This includes positioning the rocket (or multiple rockets), defining and assigning a target (or multiple targets), launching, observing the flight, and analyzing the flight results in terms of performance, accuracy and effectiveness.

Every effort was made to make this addon easy to learn for an Orbiter newbie. Playability was also a consideration: ideally, users should get more fun from playing with the addon than the developer had from making it!

Finally, I hope that addon has a very good educational potential. When making embedded scenarios, I learned numerous interesting facts about the very rich V2 history - but just barely scratched the surface. So, I would appreciate any input on making the scenarios as historically accurate as possible.

Simulation realism

Much effort was done to enhance the "behavior" realism and bring it into balance with the already excellent "static" realism. On the visual side, this had involved fine-tuning the contrails and introducing the in-flight and ground-impact explosions and smoke markers. Rocket behavior had also become more life-like due to minor randomizations. Simulation of various subsystem failures, even though truly rudimental in its current implementation, also enhances the experience.

Simulating the realistic guidance system had asked for implementing a side-by-side "ideal" guidance for comparison. There is a lot of potential in simulating the internal subsystems - and some of this potential is already realized in this addon (for now, to a very generic level). Some promising research was done on the cross-vessel and cross-class interactions.

Standalone Targeter application

End to end activity simulation means that many pre-flight and post-flight steps of the activity fall outside of the Orbiter scope. This had lead to the development of the standalone application to support these steps.

Targeter serves as a bridge between Orbiter and Google Earth. It helps to create flight scenarios based on the data from Google Earth. It also helps to analyze flight results data and visualize them in Google Earth. For more information, see the documentation on Targeter.

Testbed addon

I intend to continue to use this addon as my development testbed. So, it was important to maintain a compact code base, use only minimal Orbiter feature set and keep addon independent on any other external addons. It also means a single-stage rocket with no detachable elements.

4. What is NOT in the focus?

- Simulation of the human piloting activity.

Historical V2 was not flown manually, nor it was seriously intended to be. So is this addon. This does not mean you can't fly it manually - only that no additional helpers were designed for manual mode.

- Simulation of ground preparations activities

Such simulation would have significant educational value; however, it will require much higher subsystem detalization than was set for this addon. So, no fueling, launch tables, cable masts, etc. - for now.

- Static realism or beauty.

No consideration was applied to simple "nice look" or "realistic look" of the static model. Existing meshes and textures are already more than sufficient. Realistic behavior, not realistic looking was paramount.

- Integration with Orbiter features and/or other addons.

Every effort was taken to keep this addon as independent as possible of any external dependencies, be it other addons, previous or alternative V2 implementations or new exotic Orbiter features.

- Stages and attachments.

Historical V2 did not have any separable objects. So is this addon. Staging is a complicated issue, not supported by Orbiter to the level I want to see it. Wanting to do it right and universal (to accommodate anything from WAC stage to Canadian Arrow), I completely defer it to another version, and maybe to different addon.

- Detailed subsystems

Even though there was a significant focus on rocket subsystems, there was also a very strict limit to what level of subsystem detail was sufficient. With such conservative approach, even some subsystems already existing in prototypes (like animated vanes and rudders) were removed as overdesigned and irrelevant to the scope.

- Collision detection

For typical V2 missions, even with group launches, accidental collision chances are slim. Collision detection could then be beneficial only in combat scenarios involving antirocket defense. Historically, V2 did not encounter any of such scenarios. So, even though I have a decent collision detection in another experimental addon, it was considered irrelevant for this addon (at least for version 1).

5. Pre-empt on "militarization" rants.

If you don't like all or some of the "militaristic" advances made by this addon, read the following before ranting aloud:

1. I am well aware of your position.
2. I don't agree with it.
3. Orbiter has tons of addons that don't challenge your tolerance - so don't waste your time checking out stuff that you know you won't like.
4. As long as 1 (one) person is interested in the addon - it is worth doing.
5. I am not going to sacrifice the overall progression benefits of the addon that cannot be achieved without wading in the "militaristic" waters.

If you still want to rant, I am ready to discuss any topic... but I won't say "always ready": I am always on a tight schedule with a tough priorities list - and this topic won't be high on this list.

6. Credits.

Meshes and textures

Major credit goes to Brian Sikkema for the original V2 meshes and textures of the visual V2 model created for his NGV2 addon - they are excellent!

Code

Not much (if any) of the original V2 dll code is left – but it was a good and solid starting ground. Most of the code is new and original, but there were few minor snippets and helper functions borrowed from various Orbiter sources. They travel freely from one addon to another, and I was not able to trace them to the origin.

History

All the historical books and sites I had to go through to accomplish this addon are too numerous to be listed here. But the uber site, the most valuable and informative resource, the starting point of any research, should be named explicitly: http://www.v2rocket.com/ .