Hi all, Just wondering is someone can help. I've got my wagon working to where brakes will apply and release on it. The issue I'm noticing though is the loco will be brake Cylinder 25 odd but the wagon will be much less. Do we know what a wagon freight UK would roughly have for it's values for the various nodes on the simugraph. DTG Matt Not sure if your able to see if there is a simugraph from in house that you would be allowed to share and uncooked version that we would be able to look at to see what kind of settings the nodes etc have please .
The images above show what my wagons brakes are doing with loco brake handle in the 44% applied position and the values being read from the loco on the Hud. Unless I'm not understanding correctly things are matching from the loco brakes to the brakes on the wagon, there seems to be a difference.
I used to work in the Railway Brake Industry - although I retired 14 years ago - but I was not a systems engineer. I hope this brief explanation will help although you may know more about this subject than I do. The AIR brake system used in the UK for loco hauled stock is based on the Automatic Air Brake system "invented" by George Westinghouse in the 1870's (?) . Unlike the Straight Air Brake it uses air pressure to release the brakes to make the system fail safe. There is a Brake Pipe which runs throughout the train (connected via the hoses) and this is charged by the driver to 70 psi (gauge BP) to release the brakes.(Drivers brake valve in "Running" position). Each wagon has its own Air Reservoir (tank) which is charged from the brake pipe. Each wagon also has a special valve (called a Distributor in the UK ) which connects the Brake Pipe / Reservoir and Brake Cylinder(s) on that wagon. It includes an internal chamber (Control Chamber) which is at the same pressure as the Brake Pipe. When the driver applies the brakes the Brake Pipe pressure falls (to 57 psi in your example) and this drop is perpetuated down the train. Each Distributor (including the special type on the loco) reacts to this change in pressure by sending air from its own reservoir to the Brake Cylinder(s). (Gauge BC 44 psi in your case.) The engineers aim to get even breaking along the train although wagons and carriages (and locos) vary greatly in weight so the actual Brake Cylinder pressure for each Brake Pipe "step" for each wagon is part of the wagon design and depends on the size and number of cylinders etc. Some modern wagons even have Variable Load Valves which adjust the Brake Cylinder pressure according the weight of the wagon - detected by a special valve in the suspension. In short - in real life it is perfectly possible for different vehicles in a train to have different Brake Cylinder pressures as long as the Brake Force applied the wheels is the same so that the train doesn't bunch up or snatch the couplings. The fail safe element comes from the fact that each wagon is braked using its own air supply and if a wagon "uncoupled" the Brake Pipe pressure would be lost (0 psi) and the wagon would apply maximum Brake Pressure even if the rest of the train carried on. The wagon cannot then move at all until it is coupled again and the Brake Pipe recharged. The most modern multiple units use EP (electro Pneumatic) brake systems where the air is controlled by electrical valves which are controlled by essentially computer based "decoders" or similar which can compensate for passenger load , anti wheel slip and slide etc. but that's a different story. Hope this is some help (and not too boring !! )
DTG Matt DTG Alex DTG JD hi all, I'm just wanting to ask how would I affect my brakes animation I've made with the brakes cylinder within my simugraph. Basically so when they apply and release the animation on the brake cylinders and rigging also visual show this please.
Sorry I misunderstood your question and wandered into the brake systems rabbit hole. When I made a simple animation of a rotating ground signal disc ( skeletal mesh in Blender / vertex groups linked to the correct bones etc.) I found that although I could substitute my skeletal mesh for the one in the DTG Signal view it would simply not move. The only way I could get the parts to animate was to make my skeletal mesh use the DTG skeleton (choosing this option on import) and then it worked perfectly in game. (The skeleton in your own own model has to match the one in the game (same bone names and hierarchy) before you can do this). I think in Unreal the animations are called for in the skeleton blueprint. Hopefully DTG can advise you how to set up your own skeletal mesh to call a particular animation at the appropriate point in the game. As I'm trying to create my own loco I would be very interested in any response you receive .
So I was using the wrong thing, what you do from what I've been told is in simugraph the Brake Cylinder node have a Piston Pressure, you take this and normalise it which make to 0 - 1 and then this is what you pass into your Anim Instance and in my case I am setting the start position of the animation but not allow it to play, I'm setting animation to have play rate of 0 to do this. I haven't tested it yet but from what I could see the rig animation value in simugraph on brake rigging never actually changes from 0.0. --- On your skeleton comment, you can make your own skeletons etc you just have to do a bit more of the work yourself to get it to how you need it to be. From what I've seen the DTG stuff provides good base to see what stuff goes where in terms of various stuff so don't think too much on copying them exactly but taking what you see and working it to how you need it. If that makes sense.
Also the brake systems rabbit hole was useful it was just I then had a further question on top of my initial one .
Thanks for your replies and advice on skeletons. If I make my own skeleton / skeletal mesh and import it to the editor I guess from what you say I have to set up an animation blueprint (or an instance of it) for each animation (brakes, reverser etc.) and then use Simugraph to call the animation in game. I think I will have to watch more Unreal rigging and animation tutorials on Youtube before I can get to your level of understanding. Glad the Systems discourse helped.
