Christmas wishes

Guys, what would be your Christmas wish in the openBVE (or BVE) world? Personally, I would wish for more active developers (even though there seems to be a good bunch of guys creating stuff)...

I'd wish for a revival of the group who wanted to develop OpenBVE further, freely, as a group, just like any other open source software. We have enough active addon developers and even tool developers to go on (while of course more would be even merrier), but OpenBVE stands still. And while I know and expect some older devs to point out the longliveliness of BVE 2 and BVE 4, I am still absolutely convinced, that on the long run, stagnation is recession. Also I do not agree with the sometimes mentioned point OpenBVE would be able to do anything needed. There are plenty of things asking for development. Be it bugfighting (check on the joystick problems of some users here), be it more possibilities for the plugins (get next train's position, affect signalization etc., things which are essential to have realistic plugins for linear train protection systems like LZB or the higher levels of ETCS), be it more track variables for use in objects (e.g. a position variable allowing for kilometration signs etc.), be it more realistic brakes like Michelle had planned (check on the documentation), etc. etc. etc.

Want Santa to bwing me da nice full spec plug-in with CAWS, pretty please!!

Quork wrote:I'd wish for a revival of the group who wanted to develop OpenBVE further, freely, as a group, just like any other open source software. We have enough active addon developers and even tool developers to go on (while of course more would be even merrier), but OpenBVE stands still. And while I know and expect some older devs to point out the longliveliness of BVE 2 and BVE 4, I am still absolutely convinced, that on the long run, stagnation is recession. Also I do not agree with the sometimes mentioned point OpenBVE would be able to do anything needed. There are plenty of things asking for development. Be it bugfighting (check on the joystick problems of some users here), be it more possibilities for the plugins (get next train's position, affect signalization etc., things which are essential to have realistic plugins for linear train protection systems like LZB or the higher levels of ETCS), be it more track variables for use in objects (e.g. a position variable allowing for kilometration signs etc.), be it more realistic brakes like Michelle had planned (check on the documentation), etc. etc. etc.

Realistic brakes; you mean electric slowly fading below 20mph when the pneumatic slowly kicks in?

Definitely this. There is so many OpenBVE just doesn't do at the moment what actual trains certainly do... things like making configuration of an passenger information system easier (things like mouse clicks, instead of the long waits with hotkeys etc, try properly setting up, say, the R46 from our American friends; which takes ages to get right)

Not only. There are several brake systems acting in different ways.

• classic pneumatic single release brake:
  
  • selecting a higher brake level leads to letting out air from the brake pipe, so pressure decreases in it; the further behind a car is, the later and slower the pressure decreases
    
  • decreasing brake pipe pressure makes the car's brake control valve connect the brake air reservoir to the brake cylinder
    
  • selecting a lower brake level leads to pumping air from the main air reserovir into the brake pipe
    
  • increasing brake pipe pressure makes the car's brake control valve connect the brake cylinder to the outside till complete loss of pressure in the brake cylinder while the brake air reservoir is being connected to the brake pipe, thus being refilled (slowly only!)
    
  • this means braking, releasing and braking again leads to a loss of brake force; the brake cylinder pressure is limited a) to 3.8bar by a pressure reducer and b) by the brake air reservoir. So each time you release and brake again, there's less air for braking, till there is virtually no brake effect
    
  
  
• classic pneumatic brake:
  
  • selecting a higher brake level leads to letting out air from the brake pipe, so pressure decreases in it; the further behind a car is, the later and slower the pressure decreases
    
  • decreasing brake pipe pressure makes the car's triple valve connect the brake air reservoir to the brake cylinder
    
  • selecting a lower brake level leads to pumping air from the main air reserovir into the brake pipe
    
  • increasing brake pipe pressure makes the car's triple valve connect the brake cylinder to the outside till the brake pressure corresponds the brake pipe pressure
    
  • the brake air reservoir is refilled all the time, either from the brake pipe or, where existant, from the 10 bar main air reservoir pipe
    
  • this means there is no (or under very special conditions negligibly little) brake potential loss
    
  
  
• classic pneumatic brake with EB accelerator:
  
  • all as classic pneumatic brake
    
  • if an EB is executed, the brake pipe pressure loss is especially quick. The EB accelerator is a gadget (in a car) reacting to such a quick pressure loss in the brake pipe by opening up a hole, so that the brake pipe pressure leaves not only via the driver's active brake valve but also in the car(s), thus increasing the speed by which the pressure loss "travels" along the train and thus decreasing the time till EB takes effect in the last car
    
  • if there are too many cars in the train or if there are several cars without an EB accelerator within the train, the pressure loss speed is too low to activate the EB accelerators thus rendering them ineffective
    
  
  
• indirect electropneumatic brake (ep-brake):
  
  • just like classic pneumatic brake but additionally
    
  • in the driver's brake valve there are electric contacts in each brake level and in the brake pipe there is a pressure meter. A computer compares the selected brake level's nominal brake pipe pressure with the actual brake pipe pressure. If and as long as the brake pipe pressure is more than 0.3bar above nominal pressure, a "brake" command is sent via the ep control wire; if and as long as the brake pipe pressure is more than 0.3bar below nominal pressure, a "release" command is sent via the ep control wire
    
  • in each car (if not in all, the whole system is inactive) there are two electromagnetic valves, one (the release valve, opened by "release" command) connects the brake pipe with the main air reservoir pipe, the other (the brake valve, opened by "brake" command) connects the brake pipe to the outside
    
  • thus brake pipe pressure rises and falls and thus the brakes apply and release practically simultaneously all along the train when bigger brake level changes are executed. Changes of one step stay below the activation threshold of 0.3bar difference
    
  
  
• direct electropneumatic brake:
  
  • there is no brake pipe
    
  • the driver's brake valve is basically a simple potentiometre steering the ep control wire
    
  • the brake valve connects the main air reservoir pipe to the brake cylinder
    
  • the release valve connects the brake cylinder to the outside
    
  • all brakings are executed immediately and purely electronically
    
  • the system is redundant and fail-safe, but still probably without any further future
    
  
  

Additionally to this, there are many further aspects; gadgets increasing or decreasing brake cylinder pressure depending on speed or load, changing lever proportions for the brake leverage, different braking elements (disc brake vs. shoe brake, different brake shoes (iron, plastic, ...)), cleaning shoe brakes for disc braked vehicles, additional brakes like magnetic brakes, eddy current brakes, diverse anti sliding systems et cetera, et cetera. All of this dramatically influences how a train brakes, how it feels. Braking is the most difficult part of driving a train; and yet it's the most simplified and unrealistic aspect of OpenBVE and several other sims. That's what I meant.

Sit inside a pacer, observe how the driver brakes, how the braking feels to you as a passenger, what the brake way is. And then sit in a HST, do the same. I'm sure you'll notice a difference even from the normal passenger perspective. And now keep in mind, non-MU (but loco + cars) passenger trains (afaik you don't really have this in the UK?) behave different from MUs again; you have the buffers between the cars, you have different brake forces in the single vehicles, etc.

Simulating this was obviously planned by Michelle; the road map or the panel2 documentation (I'm not sure any more which) mentioned future variables for different brake steering systems. Making this true is an important major task, but in my eyes one not really unfeasible.

I was thinking of trying to code a plug-in for CAWS, but couldn't work it out. Will have to try and make the Autoballasters for Ballyfekin

That would be nice. Not long to Christmas so don't hang about!!

I would wish that this Forum, with its ever increasing membership, continues to grow exponentially as it has over the past 18 months. I do not subscribe to the view that OpenBve is either dead or stagnant. When I discovered OpenBve just 18 months ago there were:

1. No rotating bogie wheels.
2 No Maybank to Hammerwich and Ludgate Hill routes.
3. No Northern Line or Hammersmith & City Line.
4. No BWR
5. Brno First Track was a dream in its creator's mind.
6. No Pioneer Trains.
7. No Midland Suburban Line.

I could go on. I don't believe that the absence/resignation of ONE person should have any negative effect on the future at all. Our good friends at OpenBve Trenitalia are proud to announce their latest work. BillEWS is over the moon with his Class 91 and its mesh and bogie wheels. 100 years ago this year man first took to the air in a heavier than air machine - they said it couldn't be done. I believe the way forward is to continue ensuring that our Forum maintains its position as the best in the world, and by doing so, it will attract many more members/developers/programmers/builders etc. The best OpenBve developer has yet to be found.

Cheers,

John

Dear John, OpenBVE is stagnant. The point you did prove is the OpenBVE addon scene isn't stagnant - that, however, was never in question

Quork wrote: non-MU (but loco + cars) passenger trains (afaik you don't really have this in the UK?) behave different from MUs again

Luckily we still have plenty of non-MU passenger trains in the UK. The Class 91 + mk 4 sets recently simulated by mrknowitall are an example. Although they are push-pull they are simply a locomotive with a rake of coaches, and a Driving Van Trailer (DVT) on the other end. All of the power is from the locomotive. In East Anglia we have Class 90s on similar sets, and even HSTs are not really MUs - just rakes of coaches with a locomotive on each end. A recent addition is Chiltern's London - Birmingham trains, consisting of a Class 57 diesel, Mk3 coaches and a DVT. There are also a handful of non-push-pull scheduled services remaining, hauled by classes 47, 57, 67 and 90.

As you say, braking technique is very different (and generally more challenging) on such trains. Controlling a train with a DVT leading is particularly interesting, and it is much more difficult to keep the ride smooth in that direction.

A MU isn't necessarily powered in all cars. The ICE 1 (class 401) is two power heads and usually 14 unpowered cars inbetween. Still it is a MU, as the vehicles are permanently coupled; and such a permanent coupling is inflexible, the trainset does neither stretch nor buggle. Also, everything is set up for each other, it harmonizes perfectly, in the field of brake technics this especially means the train reacts perfectly to even the slightest brake pipe pressure adjustment.

A classic loco-car train, whether push-pull or not, is different in those matters; that's what I meant. Also, here it is very obvious why one needs seperate steering for engine braking and pneumatic braking. I suppose british drivers do the same: Start braking a little with dynamic brake so that the train buggles (if the loco is at the front) or stretches (if the loco is at the rear) smoothly, then add pneumatic braking (dynamic brake snaps in and moves proportionally with the pneumatic brake lever, I'll try to do a video, however I can't upload it for now, will wait till I have DSL) to brake more.

I'd imagine there are different definitions of what a MU actually is. None of the trains I mentioned are permanently coupled, and all can 'stretch and buckle' so by that definition they're not MUs - and anyone who has travelled on one will tell you that they certainly don't 'harmonise perfectly'! The HST could possibly be argued either way, but the other trains are very much not MUs.

Generally (although there have been exceptions) UK trains do not have pneumatic and dynamic braking separately controlled by the Driver. In most cases the Driver basically controls a pneumatic brake, into which a rheostatic or regenerative brake (as applicable) is blended automatically. In theory that's fine, but it does remove the ability to close up or stretch couplers in the way that you describe. For this reason on such trains the first brake application should be a light one (there is often a brake position marked 'initial' which gives a light brake) and that helps in ensuring a smooth ride.

Ah okay then, thanks for clearing it up!

Oh my... That's not nice. I'm quite happy about being able to control both separately and I'm making use of this all the time. Depending on the wheather, on what I want, on where I am, etc. etc.