Motion Software
Data Extraction
Portdrvr Utility
Roll & Pitch Derivative
Roll and Washout
Random Vibrations
Runway Effects
Take-off Effects
Landing effects
With the DIY Motion platform II I have done several experiments with motion cues, derived from flight parameters extracted from FS2004.  With the D/A converter driving a servo motion platform with good speed capability, there are various possibilities for achieving motion cues.

Please note that I'm not a software developer. The programs that I wrote probably look extremely crude  in the eyes of the more experienced software writer. But they seem to get the job done, and that was my only goal.  

The software examples in the various chapters are loose bits and pieces. I did not (yet) write a full program that combines all these different cues, but with some cut and paste, renaming some variables etc, it could be done without too much effort.

bulletTo get FS data from main FS computer to motion software computer, there are two great utilities available: CHComm and Portdrv. Details about these utilities and extracting data from them is described in Data Extraction. A special page is added for the Portdrvr Utility
bulletMy first experiments were based on taking the derivative of roll and pitch. Interesting, but not really successful, see Roll & Pitch Derivative
bulletSlow platform roll motion can create the aircraft banking effect. Washout (back to center) can be applied when there is no more change in bank angle. See Roll and Washout
bulletOn the runway, the wheels going over the runway grooves can be added by inducing small bumps in platform pitch. Bump frequency and amplitude can be made dependent on aircraft speed and braking, see Runway Effects
bullet During take-off, the buffeting during rotation can be added by adding high frequency vibration to the platform roll drive, see Take-off Effects
bulletHow to get the touchdown "bump" is described in Landing effects
bulletTurbulence effects can be added by adding random vibrations to both pitch and roll axis, see Random Vibrations

From the above, it can be seen that various parameters from Flight Simulator are needed to trigger certain motion cues.

For experimenting with suitable waveforms I used Excel sheets: see motion.xls

Below is a list of parameters and their motion effect possibilities:

bulletAircraft pitch: 0~255 (1 byte) to be used for tilting the platform during climb and descend. Also used to determine rotation during take-off
bulletAircraft roll: 0~255 (1 byte) to be used for detecting aircraft banking
bulletAirspeed: 0~255 (1 byte) to be used for detecting forward acceleration / deceleration
bulletGvalue: 0~255 (1 byte) to be used for detecting pulling G's, especially during turns
bulletEngine RPM 0~255 (1 byte) to be used for differentiating between landing and take-off 

Status bits:
bulletWheels on Ground (main gear and front wheel) (1 or 2 bits)  to trigger runway groove, take-off buffering, landing bumps
bulletFlaps (1 or 2 bits) for triggering flaps vibrations
bulletAirbrakes (1 or 2 bits) for triggering airbrakes vibrations
bulletGear up/down (1 or 2 bits) for triggering gear transition and gear down vibrations
bulletOverspeed (1bit) for triggering overspeed vibrations
bulletStall (1bit) for triggering stall vibrations
bulletBrakes (1 bit) for triggering extra deceleration, extra runway grooves bumps

Optional (nice to have): Slip Indicator (1 byte), Yaw (heading, 1 byte)

Back Next