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CT Only: What One Thing Would You Change About Classic Traveller?

It's totally fair to ignore all this, but at the same time see how the "reality" of it manifests in the hand wavy game world as, for example, the jump lanes. A bit of story trivia that "Frank jumped on a trader heading outsystem, their ship was tracked and looked like they were going to Alpha Prime based on their course. Can't be sure, of course, but most everyone else going out that way were going to Alpha Prime".

Or. "While in the jump lane to Gamma Hydra, you can see the uptick of patrols along the route, since that's where most of the traffic is going".

Kakistocrat said:
Do you mean the math of the celestial mechanics, the math of the orbital mechanics, or both?
Click to expand...

I went deep into the rabbit hole trying to plot a "sorta" realistic course of getting a moving ship to match vectors with a moving target and ran into differential equations, numerical methods, and a taste of vector calculus. At that point my Pooh brain went "I need more honey" and went looking for Rabbit.

And I wasn't even including gravity.

Consider this set of equations.

sx + sv + .5 * a * t1^2 + (sv + a * t1) + .5 * -a * t2^2 = px + pv * (t1 + t2)
sv + (a * t1) - (a * t2) = pv

Solve this system of equations for t1 and t2.

This problem is a ship (at sx) chasing a planet on a straight line (at velocity sv, with acceleration a), and trying to rendezvous with the planet (which is located at px and traveling at velocity pv) It simply says "Give a ship, how long should they accelerate before they start decelerating to match their position and speed with the planet".

This requires numerical methods, which typically require derivatives of the equations.

And this is only one dimension and no gravity. Two dimensions is a completely different problem. Gravity is...I don't even know.

If you can solve the two dimension course plot for this, I'll send you an Amazon gift card with which you may purchase cookies (I don't think they sell beer or pizza, sorry).
 
whartung said:
This requires numerical methods, which typically require derivatives of the equations.

And this is only one dimension and no gravity. Two dimensions is a completely different problem. Gravity is...I don't even know.
Click to expand...
Not to put too fine a point on things ... but that's what computers are for.
And when I say "computers" I mean "thinking machines" that can be programmed ... not Mentats who can pull stunts like this in front of an audience in the TL=5-6 era ... ;)


punkrabbitt said:
@whartung I must say your comment is absolutely delightful!
Click to expand...
I agree.
 
whartung said:
The computers part I don't have a real problem with, it's the ticky ticky part and what letters and numbers, and what order, to ticky ticky that I have issues with.
Click to expand...
That's where the abstraction comes in to save you (from having to do all the math in order to play). You don't need to formulate a 3D trajectory plot and use a holotank to display the results (as a Referee to the Players). You don't need to get down into the absolutist levels of data crunch in order to make things work in play.

At most, all you need is a "distance to travel in meters" and the (constant) acceleration of the craft in Gs (1G=10m/s). From those two variables you can use the LBB2.81, p10 that is just simple newtonian physics to give you an answer for time in seconds.
T = 2√(D/A)
That formula then answers how long a transit of that distance at that acceleration will take to complete (minimum, you can always make it take longer at no extra effort!).

Distance, Acceleration, Time

That's all you need (as a Referee and as a Player) in order to determine "what it's going to take to go from point to point" around a star system using maneuver drive. Everything else (direction of trajectory, gravity well effects, etc.) can all be abstracted and handwaved away by "padding out the duration" with extra time.


After that, it's just a matter of having the necessary minimum skill levels and deciding if any skill rolls are even needed (or just allow automatic success for good roleplay immersion). ;)
 
whartung said:
It's totally fair to ignore all this, but at the same time see how the "reality" of it manifests in the hand wavy game world as, for example, the jump lanes. A bit of story trivia that "Frank jumped on a trader heading outsystem, their ship was tracked and looked like they were going to Alpha Prime based on their course. Can't be sure, of course, but most everyone else going out that way were going to Alpha Prime".

Or. "While in the jump lane to Gamma Hydra, you can see the uptick of patrols along the route, since that's where most of the traffic is going".
Click to expand...

Heh, this pretty much sounds a lot like my games, especially with non-science types....

whartung said:
I went deep into the rabbit hole trying to plot a "sorta" realistic course of getting a moving ship to match vectors with a moving target and ran into differential equations, numerical methods, and a taste of vector calculus. At that point my Pooh brain went "I need more honey" and went looking for Rabbit.

And I wasn't even including gravity.

Consider this set of equations.

sx + sv + .5 * a * t1^2 + (sv + a * t1) + .5 * -a * t2^2 = px + pv * (t1 + t2)
sv + (a * t1) - (a * t2) = pv
Click to expand...
See the question here is this good game play.

Which brings me around to the point of vector movement. Honestly except for a couple of rules sets they it has been largely ignored. While I am not saying to remove it as an option, I am saying a more friendly hex based wargame solution would be nice. (More than once I have pondered a Star Fleet Battles like solution to this question).
 
infojunky said:
Which brings me around to the point of vector movement. Honestly except for a couple of rules sets they it has been largely ignored. While I am not saying to remove it as an option, I am saying a more friendly hex based wargame solution would be nice. (More than once I have pondered a Star Fleet Battles like solution to this question).
Click to expand...
Both Mayday and Brilliant Lances put vector movement on hex boards.
 
whartung said:
Consider this set of equations.

sx + sv + .5 * a * t1^2 + (sv + a * t1) + .5 * -a * t2^2 = px + pv * (t1 + t2)
sv + (a * t1) - (a * t2) = pv

Solve this system of equations for t1 and t2.

This problem is a ship (at sx) chasing a planet on a straight line (at velocity sv, with acceleration a), and trying to rendezvous with the planet (which is located at px and traveling at velocity pv) It simply says “Given a ship, how long should they accelerate before they start decelerating to match their position and speed with the planet".

This requires numerical methods, which typically require derivatives of the equations.
Click to expand...
Yup. Some variant of Newton’s Method might be useful for this type of problem, but it’s been a long time since I last sat in a calculus class, so perhaps other methods would be better suited to it. I’d imagine that software such as MATLAB (or a gratis work-alike like Octave) could be used to model this sort of problem, but I have no experience with software of this type.

whartung said:
And this is only one dimension and no gravity. Two dimensions is a completely different problem. Gravity is...I don't even know.
Click to expand...
A planet’s orbit would also be elliptical, so the semi-major axis of the orbit and one or both of the planet’s periapsis and apoapsis would also be among the data needed in determining a phasing orbit for an inbound ship to be able to rendezvous with the planet’s starport.
 
Kakistocrat said:
Yup. Some variant of Newton’s Method might be useful for this type of problem, but it’s been a long time since I last sat in a calculus class, so perhaps other methods would be better suited to it. I’d imagine that software such as MATLAB (or a gratis work-alike like Octave) could be used to model this sort of problem, but I have no experience with software of this type.


A planet’s orbit would also be elliptical, so the semi-major axis of the orbit and one or both of the planet’s periapsis and apoapsis would also be among the data needed in determining a phasing orbit for an inbound ship to be able to rendezvous with the planet’s starport.
Click to expand...
It's a game -- simplify it. Assume circular orbits unless you need to make a plot point out of it. Transits in Traveller are fast enough burn-flip-decel runs that you can mostly disregard orbital movement over a typical interplanetary trip.
 
infojunky said:
Which brings me around to the point of vector movement. Honestly except for a couple of rules sets they it has been largely ignored. While I am not saying to remove it as an option, I am saying a more friendly hex based wargame solution would be nice.
Click to expand...
I am doing something like this with cepheus, converting the range bands to hexes.
 
Been pondering things of CT... Book2 Combat turn order probably could use some work...

Consider this;
1. Movement, all ships move in order of their of the vector length, longest vector goes first... Then Missiles and sand moves.
2. All fire happens, including point defense.
3. Damage applied from previous phase

Note I am assuming the simplified computer rules here.

Also Note in Phase 1; Movement probably all planetary and satellite movement should lead...
 
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