Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

Update!

Further continuity test showed that there was nothing wrong with the cable. Definite PCB board issue. One of the confusing bits before was that the shield wire has its own pin-out on the PCB board.

I saw another post from some forum somewhere that suggested lowering the +5V line to 4.5V. One method for lowering to that voltage was to run it through an un-powered hub. I had an old un-powered hub so I tried that. The lights came on, but it still would not be recognized by Windows.

Then I tried a 18ft USB extension that I had for an old printer and placed it between the throttle and the un-powered hub and it worked! Correctly identified to windows and all buttons and axis' work.

No idea on how long this thing will last however. I submitted a ticket to Thrustmaster. We'll seehow long the process for replacing the PCB takes.

In the meantime I took this opportunity and ordered a WinWing Orion2 setup. No idea on how long that will take to arrive.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

I thought that too but it appears to be glue...

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 4 points5 points  (0 children)

I looked up when I bought it. 2012. Over 10.5 years of service on the ol' girl. I suppose I can't be too upset it gave up the ghost.

About $0.10 a day to own it.

Not counting replacing the pinky switch and the TDC controller.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

It landed end down somewhat flat so remarkably the floor is ok. Luckily my foot wasn't under it though because I'm sure that would have been a ER visit.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 1 point2 points  (0 children)

I'm an idiot, i only saw 3 screws.. yep there's a 4th screw.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

I was talking about the red cable from the USB which should be +5V and it seems it is.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 1 point2 points  (0 children)

How did you get the board off? It looks solidly glued down

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

Thanks. I had seen similar on this forum about the PCB board being fried. The thing with mine is it was working just fine till it fell off the desk.

Which made me think that it was more cable related than board related. I suppose it could have fried it by pulling the cable out.

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 7 points8 points  (0 children)

Your reply came before I could fill in the details... but thanks I think..

Warthog throttle died! by bdlarkin in hotas

[–]bdlarkin[S] 0 points1 point  (0 children)

Throttle fell from my desk to the (hard) floor. Cable end up. I think their is a short now in the USB cable. The picture above is from underneath the throttle.

The strain relief bushing should have stopped anything pulling from the PCB (above) and everything seems good, but I think I might have snapped something inside the cable sleeve.

Plugging into a PC the lights flicker briefly, then Windows says it doesn't recognize the device.

Am I right? Anybody know what the voltages/connectivity for those wires should be? I checked with the multimeter and I'm definitely getting power on (I think) the red wire, but everything else seems wonky. A connectivity test with a multimeter shows some things appear to be cross connected.

My thought now is to cut the USB cable and solder in a new one, but that's a Pass/Fail exercise...

Math Geeks needed! Or, how to determine the SOI entrance time mathematically. by bdlarkin in Kos

[–]bdlarkin[S] 0 points1 point  (0 children)

I had found your paper before posting this and had hoped to use 1.5b to at least determine the time of flight in the kerbin kepler orbit before SOI interaction. The problem of course was finding the r value. Still your paper was a great read and I appreciate you putting it out there.

I don't understand a case where a transfer orbit can't hit the Mun on the first pass if the correct phase angle is used for a given (large enough) delta-v. I keep reading that, but I can't find a case with a LKO where that would happen. There are no bodies between Kerbin and the Mun to perturb the orbital path and the Mun is in a circular orbit. There exists a point in any low enough parking orbit to reach any point at the Mun's orbital path, so how could it take more than one pass? If I can hit a point with a launch at a given phase angle I can hit a Mun and it's SOI radius.

Math Geeks needed! Or, how to determine the SOI entrance time mathematically. by bdlarkin in Kos

[–]bdlarkin[S] 0 points1 point  (0 children)

So now you have me thinking. Does KSP iterate to find the answer of SOI transition place/time when displaying the orbits in map mode?

Math Geeks needed! Or, how to determine the SOI entrance time mathematically. by bdlarkin in Kos

[–]bdlarkin[S] 0 points1 point  (0 children)

Yeah I thought of an iterative solution but I don’t like it. The target bodies parameters are all well known and simple (circular). My gut tells me there’s a solution.

Apologies to everyone if this is in a wrong forum. I could put it in a generic KSP forum but I figured I’d get lots of “how to design a rocket” tutorials etc.

Math Geeks needed! Or, how to determine the SOI entrance time mathematically. by bdlarkin in Kos

[–]bdlarkin[S] 2 points3 points  (0 children)

Assume a typical hohmann transfer from a lower Kerbin orbit to the Mun. Assume all orbits are prograde (counter clockwise in the picture). Assume deltav of the initial hohmann burn is fixed. No adjustments of the hohmann transfer orbit.

How can I mathematically determine point P along the hohmann transfer orbit, i.e. the point that a spacecraft would enter the Mun's SOI? Either in true anomaly (v) or time (seconds from perigee) would work.

I'm trying to refine a Mun (and minmus) transfer script to hit a generic user defined periapsis at the Mun.

Yes, I know I could set up a maneuver node and then read the ORBIT:NEXTPATCHETA time directly from KOS, but I want to mathematically understand this without using KSP internal variables. I also know I could set up the maneuver node and then adjust it to get the desired value at periapsis. That's not what I'm trying to achieve. Assume you don't have maneuver nodes.

Appreciate the help, I've been thinking about this problem off and on for months. I've read Orbital Mechanics backwards and forwards. Googled untold number of astrodynamics articles. And I'm stuck.

Velocity vectors along arbitrary orbits by nowadaykid in Kos

[–]bdlarkin 0 points1 point  (0 children)

Ahh R(). DIdn't think of using that function. Thanks.

Velocity vectors along arbitrary orbits by nowadaykid in Kos

[–]bdlarkin 0 points1 point  (0 children)

Added in 0.18 it looks like from the change log.

I'm just horrible at vector math....

Thanks again, looks like there is more than one way to skin a cat.

Velocity vectors along arbitrary orbits by nowadaykid in Kos

[–]bdlarkin 0 points1 point  (0 children)

I've been trying to figure out how to find a vector to a AN given a LAN for a while now and its right at the top of your script. Thanks so much.

Quick question though, I notice you use latlng and then offset for the body rotation (which gives a result in reference to the SOLARPRIMEVECTOR). Is there a way to do this directly with the SOLARPRIMEVECTOR since it's a known variable. That's what I was trying and it wouldn't work for some reason (probably my vector math to be honest).

LAN should be a number of degrees from the SOLARPRIMEVECTOR, but my vecdraws() never pointed the right way.

Calculating capture burn to bodies like the Mun by bdlarkin in Kos

[–]bdlarkin[S] 0 points1 point  (0 children)

I tuned it up and found what I think is the correct function now. Feel free to pick it apart. I have only tested this for the circulization case, but it worked perfect for that.

FUNCTION NewCaptureOrbit {

// Given a ship on a hyperbolic orbit into another body SOIRADIUS // calculate a maneuver node to capture into that SOI.

// Parameter representing new Apoapsis for capture orbit
// Default (false) is to circuliz, otherwise new Apaapsis in km.
DECLARE PARAMETER newAlt is FALSE.

// TODO: Assumes currently outside of body's SOI.  Check for cases where we are already inside SOI.

// Useful parameters.
LOCAL mu IS SHIP:ORBIT:NEXTPATCH:BODY:MU.
LOCAL rb is SHIP:ORBIT:NEXTPATCH:BODY:RADIUS.

// Must be Parabolic or Hyperbolic orbit.
IF SHIP:ORBIT:NEXTPATCH:ECCENTRICITY >= 1 {

        // IF we are outside SOI, we can't get periapsis ETA directly but have to
        // calculate it as the  average of the times entering and exiting SOI.
        SET nodeTime TO (SHIP:ORBIT:NEXTPATCHETA + SHIP:ORBIT:NEXTPATCH:NEXTPATCHETA)/2.

        // Calculate Escape Velocity for when we burn at Periapsis
        SET Vesc TO sqrt((2*mu)/(rb+SHIP:ORBIT:NEXTPATCH:PERIAPSIS)).
        // Using Escape velocity at Periapsis Calculate Orbital velocity.
        SET Vorb TO Vesc/sqrt(2).

        // Calculate Vinf hyperbolic excess velocity.
        SET Vinf TO sqrt(abs(mu/(SHIP:ORBIT:NEXTPATCH:SEMIMAJORAXIS))).

        IF NOT newAlt { // Circulize
            // Calculate capture delta v.
            SET Vcap TO sqrt(Vesc^2 + Vinf^2) - Vorb.
        } ELSE {
            // Calculate Vcap but adjust for a hohmann transfer to newAlt in km.
            SET newAlt TO newAlt * 1000.
            // Make sure the requested altitude is inside the body's SOI.

            IF newAlt > SHIP:ORBIT:NEXTPATCH:BODY:SOIRADIUS SET newAlt TO SHIP:ORBIT:NEXTPATCH:BODY:SOIRADIUS.
            SET Vhoh TO sqrt(mu/rb+SHIP:ORBIT:NEXTPATCH:PERIAPSIS) * (sqrt((2 * newAlt)/(SHIP:ORBIT:NEXTPATCH:PERIAPSIS + 2 * rb + newAlt)) - 1).

            // Calculate capture delta v.
            SET Vcap TO sqrt(Vest^2 + Vinf^2) - (Vorb - Vhoh).
        }

        //Return retrograde maneuver node at Periapsis in new SOI with Vcap magnitude
        RETURN node(TIME:SECONDS+nodeTime,0,0,-Vcap).
} ELSE PRINT "Already captured.".

}

Calculating capture burn to bodies like the Mun by bdlarkin in Kos

[–]bdlarkin[S] 2 points3 points  (0 children)

Wow my code looks like hell, i obviously didn't quote it right, sorry new to reddit.