Thread: Simulator setup
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Old 06-10-2013, 07:35 AM   #1 (permalink)
ArchmageAU
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Default Simulator setup

I have seen many questions on how to set up a simulator. Phoenix, RealFlight, Heli-X, ClearView, etc. Each simulator is relatively easy to set up once you understand the basic principles. This is what I will explain. I have also provided details my Heli-X setup with a DX8.

I will try put up more examples in the next few of days (if requested). Possible examples can be Phoenix, ClearView and/or FMS (may also look at neXt).


The Basics:

How a simulator works.

A simulator takes control inputs and manipulates a model on a screen based on those inputs. This much is not hard to understand. The part that confuses people is how does the computer determine what to do with the model based on the control inputs.

Each simulator has a 3D virtual landscape to fly the model in (usually labelled as an airport). Quite often this environment is a photo box (a 360 degree photo that you can look around in). The other environments are full 3D environments. You can only move the pilot in a full 3D environment. In a photo box environment, you can only change the direction you are looking, not the pilot. This is why FPV simulation can only work in a full 3D environment.

Now that we have a virtual flying environment, we need to put things in it, ground, water, trees, buildings, etc.. Each object (including ground) is represented as an object in the environment. Each object must have location and size (and optionally graphics, yes some items may be invisible since the graphic may be part of the photo box). Once an object is defined, a virtual heli can collide with it. Some of these objects are native to the field (like ground and trees), others can be defined separately and used in multiple environments (such as boxes or flags).

Now we have an environment, we need a heli to fly in it. The model must have a shape and a graphic. This way you can see it, control it and collide it with things. Each model will also have a number of flight parameters (usually quite a lot). This enables the simulator to emulate the movement of the heli. Every simulator I have tried enables a user to modify how a heli behaves. Getting a model to behave right is a combination of two things. The first is the accuracy of the model parameters in relation to the simulators physics engine. The second is the physics engine itself.

If the physics engine is good, we can make a heli perform in the sim like real life. If the physics engine is bad, regardless of how we tune the heli parameters, there will be things that do not line up to real life flying. For example, if your simulator under-values heli mass, then it will need reduced thrust to keep it in the air (slower rotor speed, shorter configured blades, etc). We may be able the tune the flight so it works right, but auto-rotations will be too easy and the heli will feel more "floaty". This is why we evaluate the simulator physics.


Physics:

Modelling the physics of a helicopter is very complex. As well as stationary lift and transitional lift, there is ground effect, autorotative states, blade stall, anti-torque compensation and other artefacts to emulate. Good simulators emulate all listed above and more. The more they emulate, the close to reality the simulator feels.

Can you learn to fly on a sim with poor physics? Yes. The basic principals of flying work on even the poorest of sims (like FMS).

Can you hone and tune your flying on a sim with poor physics? Not really. As some aspects will seem far easier than others, and fine tuning responses in a "partially correct" environment.

RealFlight 6.5 and Heli-X both emulate effects such as tumbling in a blade stop autorotation and tail instability when main rotor speed is too slow. The German creators of Heil-X have developed a video series demonstrating an number of helicopter physics principals. If looking for realistic physics, as of June 2013, RealFlight 6.5 is generally recommended. I personally also recommend Heli-X in this area as well.


Controller:

Ideally your controller should be as close to the transmitter you use to fly your helicopter as possible. You can learn the basic reactions with something as simple as and xbox controller, but having a real feeling transmitter is more helpful.

There are two main options for a controller, dedicated 2 stick device (with optional buttons) like RealFlight, or table to link to trainer port on actual transmitter. In either case the input control device must be calibrated so the simulator knows the hich and low values of each input channel.

A dedicated two stick device relies on the simulator to emulate the transmitter programming. Settings such as DR&expo, pitch curve, throttle curve, gyro gain (and others like flight mode and throttle hold) need to configured. These configurations will be done in the simulator. Flight modes may be per helicopter, or overall for the simulator, or a mixture of both.

Using the trainer port on a transmitter, only the resultant output of the channels is sent to the simulator (not the actual switch and button actions). This is important to realise. When you click TH on your TX, the output settings on the throttle channel drop (usually to 0, but whatever you programmed them to). The gyro switch should operate the gyro channel, etc. Correct programming of your transmitter is crucial for calibration to the computer. You may then have to re-calibrate for correct operation. More on that soon.


Controller selection:


If your simulator does not come with a purpose built cable (like Phoenix), or a purpose built transmitter replacement (like RealFlight), you will need a pseudo transmitter (controller) or a way to connect your transmitter to the computer.

I started off with a USB pseudo 4ch transmitter which was for FMS. It was mode 1, but I converted it to mode 2 when I switched to learning mode 2. If you are just starting and selecting a mode, I highly recommend mode 2. For more information see "Transmitter mode" section of "From tail-in to all 8s and funnels in 6 months" - https://www.helifreak.com/showthread...70#post5003370.

if connecting your transmitter to the computer, find a trainer to USB method. Some sites suggest you can use PPJoy or TXPPM. In short do not waste time on these for helicopter simulation. These rely on sampling the PPM audio signal from a trainer port and converting it into a joystick interface signal. I have had little success with these since the PPM signal is very fast (50ms packets with signal bursts 1ms - 2ms long) and it takes computing time to convert the audio signal into the joystick signal which is already being used for the computationally intense simulators and display.

For a list of transmitter to USB or pseudo transmitters, I usually direct people to the Heli-X support site (http://www.heli-x.net/support_e.shtml), other options can be researched by the reader.


Controller Calibration:

As mentioned, calibration is required for control devices. The computer represents and input from an analog device (such as a stick as a digital number. These numbers range from 0 to 2147483648 (2^31) (sometimes even greater if unsigned or 64 bit). The low point of a stick is almost never 0. The high point on a stick in almost never maximum. Consequently the simulator must determine what the low and high points are. The middle is always determined to be the middle of high and the low points. This is why calibration asks you to move the sticks around and centre the sticks. By measuring the endpoints and the centre, the input ranges can be stored by the simulator.

For a dedicated two stick controller device, this calibration process is easy, the input is always linear. With a transmitter this is trickier.

If using a transmitter and feeding from the trainer port, you will need to set the model for calibration to as basic as possible. Easiest way to accomplish this is to create a new heli model in your transmitter. Call this model simcal (short for simulator calibration). Ensure the throttle and pitch curves are both linear (0,25,50,75,100) in normal mode, the gyro switch goes from -100 in low rate to +100 in high rate, and any other switches that control other channels use the linear full range. Use this model for calibration (and simming if using the sim to control the parameters instead of the transmitter programs).

Once you have your transmitter ready, calibrate your sim and save the calibration settings.


After calibration:

If using a dedicated two stick device, or using your transmitter as a dedicated two stick device, you will need to tell the simulator how to emulate your transmitter programming settings.

If you use your programmable transmitter as a 5 or more channel input device, you will need to set up a sim model with the settings you want AND tell the simulator NOT to emulate these settings as if you had a linear controller.

Whichever method you choose, the normal and idle up settings need to be created. Any change to DR, expo and/or travel adjust needs to be made. Gyro settings will also need to be created.


Heli selection:

Temptation is to use the heli you are flying (if that model is available in your sim). If you are flying a heli bigger than a 450 size heli, this is fine. If you are flying a heli 450 size or smaller, go for a 600 or 700 size heli.

If you intend to fly flybarless, choose a large flybarless heli. If you intend to fly flybared, choose a large flybared heli

The reason for sticking with larger helis is twofold. Firstly, the emulation of the physics of small helis is usually so far out that you spend more time training reflexes than flying control (all emulations I have flown of a 130, fly almost nothing like my real 130). Secondly, small helis become hard to see on a sim very fast.

Once you have selected a heli, you may need to adjust it's properties to resemble how yours performs. Adjust roll rate, tail rate, governor speeds, tail sensitivity, mass, blade length, blade chord, air resistance and other parameters. If you do not know how to adjust these parameters, or the effects they will have on the model, just fly the large heli on it's default settings.


Summary:

  • Understand how a sim works.
  • Calibrate your controller.
  • Setup your controller and heli parameters.
  • By preference use appropriate bigger helis.


Example setup 1:

This is taken from my actual setup.

Assumptions:

  • DX8
  • USB interface
  • Heli-X

DX8 model "SimCal" (used for calibration)
  • Type: Heli
  • Swash Type: 1 Servo Normal
  • Switch Select: Gov/Aux2 - Knob/Aux3 - All other Inh
  • Flight Mode: F Mode - Hold: Hold
  • Servo Setup (all): No sub trim, No travel adjust, Speed normal, Normal (not reversed)
  • DR & Expo (all): DR 100 / Expo 0
  • Throttle Cut: Inh
  • Throttle Curve: (N 0,25,50,75,100 - 1 100,100,100,100,100 - 2 100,100,100,100,100 - H 0,0,0,0,0)
  • Pitch Curve (all - N,1,2,H): 0,25,50,75,100
  • Gyro: Ch/Gear - Sw/Gyro - (0,-100.0 / 1,0.0 / 2,100.0)
  • Governor: Inh
  • Tail Curve (all - N,1,2,H): 0,0,0,0,0
  • Mix (no changed settings)
  • Timer: 5:00 min - Count down - Trainer

DX8 model "Sim"
  • Type: Heli
  • Swash Type: 1 Servo Normal
  • Switch Select: Gov/Aux2 - Knob/Aux3 - All other Inh
  • Flight Mode: F Mode - Hold: Hold
  • Servo Setup (all): No sub trim, No travel adjust, Speed normal, Normal (not reversed)
  • DR & Expo (all): DR 100 / Expo 20 (my preference)
  • Throttle Cut: Inh
  • Throttle Curve: (N 0,25,50,75,100 - 1 100,100,100,100,100 - 2 100,100,100,100,100 - H 0,0,0,0,0)
  • Pitch Curve (all - N,1,2,H): 0,25,50,75,100
  • Gyro: Ch/Gear - Sw/Gyro - (0,-100.0 / 1,0.0 / 2,100.0)
  • Governor: Inh
  • Tail Curve (all - N,1,2,H): 0,0,0,0,0
  • Mix:
    • Mix1 - Aux2>Thr -30,-50,0 (1 only)
    • Mix2 - Aux2>Thr -10,-20,0 (2 only)
  • Timer: 5:00 min - Count down - Trainer

(This setting means for Idle up 2, Aux2 switches throttle from 90,100,80 and Idle up 1, Aux2 switches throttle from 70,100,50. This means I can have flat 100,90,80,70 and 50 throttle curves).

(Heli-X does not use gyro, otherwise would change gyro setting to better reflect throttle speed).

After starting Heli-X in the Controller configuration:
  • Check use 5 channels
  • Check ignore thrust / pitch curves
  • Check ignore dual rate / expo settings
  • Collective pitch is stick S_5_y
  • Cyclic roll is stick S_0_x (inverted)
  • Cyclic nick is stick S_1_y
  • Rudder is stick S_4_rz
  • Engine Speed is stick S_3_slider
In Buttons setting:
  • Trigger (invert) is set to Idle Up 1 (Gyro switch 0 or 1)
  • Top is set to Idle Up 2 (Aux 3)
In Keyboard settings:
  • Toggle Pause Resume is set to SPACE
  • Instant Zoom In is set to F11
  • Instant Zoom Out is set to F12

I edited the files/controller/<controller-name>.xml to match up the ServoPlus, ServoMinus and Offset for all the calibrated channels (for fine tuning).

I edited the start position of the Airport Dietersdorf to -8.2,5,-2.6 (from -5,5,0). This places the heli on the dot in the middle of the road for launch. This was done through the edit button in the Airport Selection menu (edit the selection, press return, then press save button, close edit window, select another airport, then go back to airport selection and select the one you edited). You may want to move the heli launch position further away again so you are not standing inside the hover training circles (-8.2,5,-7.6).

I use mainly the Logo 600. In the Flight Mode configuration, I have the gyro gain set to 95.0/65.0 for Idle up 1 and 2 and 75.0/45.0 for Autorotation. Because I use "5 channel" mode, the DR, expo, throttle and pitch settings are taken from the TX, not the Flight Mode configuration.

If I was not using "5 channel" mode, I would have to emulate the DR, expo, throttle and pitch settings in the Flight Mode configuration for Idle Up 1, 2 and Autorotation. I would also have to set keys for Idle Up 1, Idle Up 2 and Autorotation (usually 1, 2 and A).


Do you want more example setups?

I will try put up more examples in the next few of days (if requested). Possible examples can be Phoenix, ClearView and/or FMS (may also look at neXt).


References:

"From tail-in to all 8s and funnels in 6 months" - https://www.helifreak.com/showthread...70#post5003370
Heli-X support site - http://www.heli-x.net/support_e.shtml
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