TH-2 Support  - VTOL Control Software                                                                                                
 

    Last updated on: 08-30-08

 

Special thanks to:

Walt Ferar
Eyal Miron
Richard Addington
Rudy Resch
Larry Chapman

 

For their contributions and efforts towards the development of this version of TH-2 software.



TH-2  VTOL/Tandem Control Software Online Users Guide

VTOL/Tandem Control Software Specifications
VTOL Control Software Block Diagram
VTOL Control Software Flight Controls

Tandem Control Software Flight Controls

Radio Settings
Software Control Constants

VTOL/Tandem Control Software General Information



VTOL/Tandem Control Software Specifications

Version: VTOLA001  VTOL/Tandem helicopter control software

CCPM Mixing types Supports 2 and 3 point
Number of servo outputs 8 total, 4 left/front and 4 right/rear. A,E,P for CCPM swashplate, E-prime for Flaps and Flaperons
Servo reversing All 8 outputs
Servo centering All 8 outputs with +/- 12.5% travel
Required inputs 5, Aileron, Elevator, Rudder, Pitch, CH5
Optional inputs None
Modes 2, Helicopter, Airplane;  Selected by CH5
Input gain control H-Mode 5, Aileron (0..100%), Elevator (0..100%), Rudder (0..100%), Pitch (0..100%), DCP (-100%..100%)
DCP input source H-Mode 4, Aileron (1), Elevator (2), Rudder (3), Pitch(4)
Input gain control A-Mode 5, Aileron (0..100%), Elevator (0..100%), Rudder (0..100%), Pitch (0..100%), DCP (-100%..100%)
DCP input source A-Mode 4, Aileron (1), Elevator (2), Rudder (3), Pitch(4)
CH5 H/A Mode Switch Point (0..100%)
H-Mode Flap Positions 3, Neutral, Flap1, Flap2
A-Mode Flaperons gain control (-100%..100%)
A-Mode Flaperons input source 4, Aileron (1), Elevator (2), Rudder (3), Pitch(4)
CP layout control Select swashplate up/down will increase/decrease CP
Front swashplate layout Select the E servo to face front/rear (3-point only)
Rear swashplate layout Select the E servo to face front/rear (3-point only)
Yaw axis selection 2, Roll  " Lateral" (1), Pitch  "Longitudinal" (2)
H-Mode Pmix 3, Gain (-100%..100%), Input sources (4),  Output channels (4)
A-Mode Pmix 3, Gain (-100%..100%), Input sources (4),  Output channels (4)


VTOL Control Software Block Diagram

Coming soon...



VTOL Control Software Flight Controls

Coming soon...



Tandem Control Software Flight Controls

The TH-2 provides four basic flight controls - Yaw, Pitch, Roll and Vertical ascent/decent.
These controls map to the familiar transmitter joysticks layout (mode 2).

  • Yaw - Left transmitter joystick LEFT/RIGHT.
     

  • Vertical ascent/decent - Left transmitter joystick UP/DOWN.
     

  • Roll - Right transmitter joystick LEFT/RIGHT.
     

  • Pitch - Right transmitter joystick UP/DOWN.

   


Yaw Control

The TH-2 performs yaw control by tilting the front and rear swashplates differentially along the roll axis.

   



Roll Control

The TH-2 performs roll control by tilting the front and rear swashplates along the roll axis.

   

 


Vertical Ascent/Decent  Control

The TH-2 performs Vertical ascent/decent control by increasing/decreasing the front and rear rotor pitch collectively (each the same).
This is known as collective pitch.

   

 


Pitch  Control

The TH-2 performs performs Pitch control by increasing/decreasing the front and rear rotor pitch differentially.
This is known a Differential Collective Pitch (DCP).
It also blends in for/aft cyclic with the ratio determined by the gain settings.

 

   


 



Radio Settings

This section describes what the settings in your transmitter should be.

In general, start off with the servo travel (ATV, end point, etc.) set to 100% for aileron, elevator, rudder, pitch and CH5. 
This will give you a good starting point.  Servo reversing will depend on how you installed your servos and the brand as well. 
All CCPM swashplate mixing must be turned off.  Initially, all other mixing functions should be turned off. 

After you have things working, you can them add programmable mixes done by the TX.



Software Control Constants


The TH-2 VTOL/Tandem Control Software uses control constants as programmable parameters to allow customization
for many different applications and model types.  These control constants can be modified, loaded, saved and shared
with other users using our Tech Link Software.  Below the details of each control constant are listed:



Servo Reversing

Modify Constants - 1

Functions:

  • Set servo direction normal/reverse
     

This is used to set the direction on all 8 of the servo outputs. The direction that a servo arm moves also depends on the brand of servo
and which side the arm is mounted on.



Servo Centering

Modify Constants - 2..9

Functions:

  • Set servo centering position -12.5..12.5 percent
     

This is used to set the centering (servo neutral position) on the servo outputs. 
It provides a range of +/- 12.5 percent which is more than half way on most splined servo output shafts.



H-Mode Aileron Channel Input Gain

Modify Constants - 10

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



H-Mode Elevator Channel Input Gain

Modify Constants - 11

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



H-Mode Pitch Channel Input Gain

Modify Constants - 12

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



H-Mode Rudder Channel Input Gain

Modify Constants - 13

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



H-Mode DCP Channel Input Gain

Modify Constants - 14

Functions:

  • Adjust gain -100..100 percent
     

The input gain is adjustable from -100 to +100 percent.  Set to 0 to disable this channel.  The dual polarity allows you to easily change which
direction this input operates. 



H-Mode DCP Input Source

Modify Constants - 15

Functions:

  • Select input source  1 = Aileron, 2 = Elevator, 3 = Rudder , 4 = Pitch
     

Select the H-Mode source for the DCP input. 



A-Mode Aileron Channel Input Gain

Modify Constants - 16

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



A-Mode Elevator Channel Input Gain

Modify Constants - 17

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



A-Mode Pitch Channel Input Gain

Modify Constants - 18

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



A-Mode Rudder Channel Input Gain

Modify Constants - 19

Functions:

  • Adjust gain 0..100 percent
     

The input gain is adjustable from 0 to +100 percent.  Set to 0 to disable this channel.



A-Mode DCP Channel Input Gain

Modify Constants - 20

Functions:

  • Adjust gain -100..100 percent
     

The input gain is adjustable from -100 to +100 percent.  Set to 0 to disable this channel.  The dual polarity allows you to easily change which
direction this input operates. 



A-Mode DCP Input Source

Modify Constants - 21

Functions:

  • Select input source  1 = Aileron, 2 = Elevator, 3 = Rudder , 4 = Pitch
     

Select the A-Mode source for the DCP input. 



CH5  H/A-Mode Switch Point

Modify Constants - 22

Functions:

  • Sets the switch point for H-Mode or A-Mode  0..100%
     

The mode is H-Mode when CH5 < switch point setting and the mode is A-Mode when CH5 > switch point setting. 
Setting the switch point to 0% will keep the mode in H-Mode.

Note:  The red status LED blinks twice as fast when in A-Mode.  This was done so you can easily tell which mode the unit is in.



H-Mode Flap 1 Trigger Set Point

Modify Constants - 23

Functions:

  • Sets the switch point for Flap 1  0..100%
     

The flaps are set to neutral until CH5 >=  Flap 1 trigger set point. Then move to the Flap 1 position setting.
Set the Flap 1 position to 0% to disable this function.



H-Mode Flap 1 Position

Modify Constants - 24

Functions:

  • Sets the Flap 1 position  -100..100%
     

The flaps position can be set to full travel in either direction -100% to 100%
Set the Flap 1 position to 0% (neutral) to disable this function.



H-Mode Flap 2 Trigger Set Point

Modify Constants - 25

Functions:

  • Sets the switch point for Flap 2  0..100%
     

The flaps are set to neutral or Flap 1 until CH5 >=  Flap 2 trigger set point. Then move to the Flap 2 position setting.
Set the Flap 2 position to 0% to disable this function.



H-Mode Flap 2 Position

Modify Constants - 26

Functions:

  • Sets the Flap 2 position  -100..100%
     

The flaps position can be set to full travel in either direction -100% to 100%
Set the Flap 2 position to 0% (neutral) to disable this function.



A-Mode Flaps Gain (Flaperons)

Modify Constants - 27

Functions:

  • Sets the Flaperons gain  -100..100%
     

The flaps operate as flaperons in A-mode. They move differentially.  The  -100% to 100% gain range allows their movement to be reversed.
Set the gain to 0% to disable this function.



A-Mode Flaps Input Source

Modify Constants - 28

Functions:

  • Select input source  1 = Aileron, 2 = Elevator, 3 = Rudder , 4 = Pitch
     

Select the A-Mode source for the flaperons input. 



Collective Pitch Layout

Modify Constants - 29

Functions:

  • Select CP swashplate movement
     

This is used to select whether the CP increases by moving the swashplates up or visa versa.



Right/Rear Swashplate Servo Layout (3-point)

Modify Constants - 30

Functions:

  • Selects position of the E servo
     

This is used to select the position for the rear swashplate E servo (facing front or rear). 
This setting is only used if the CCPM type is set to 3-point.



Left/Front Swashplate Servo Layout (3-point)

Modify Constants - 31

Functions:

  • Selects position of the E servo
     

This is used to select the position for the front swashplate E servo (facing front or rear). 
This setting is only used if the CCPM type is set to 3-point.



Yaw Axis Selection Gain

Modify Constants - 32

Functions:

  • Select axis for yaw  1 = Roll, 2 = Pitch,


This is used to select which axis the yaw functions applies to.  For Roll, the swashplates will tilt sideways differentially (roll axis) and for
Pitch,  the swashplates will tilt for/aft differentially (pitch axis). 
Roll would be selected for a tandem helicopter (CH46, CH47 etc.)  Pitch would be selected for a coaxial (V22, Kamax etc.)



H-Mode Pmix 1 Source

Modify Constants - 33

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to H-Mode programmable mixer 1.
Set the input to 0 to disable this function.



H-Mode Pmix 1 Output Channel

Modify Constants - 34

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to H-Mode programmable mixer 1.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



H-Mode Pmix 1  Gain

Modify Constants - 35

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for H-Mode programmable mixer 1.



H-Mode Pmix 2 Source

Modify Constants - 36

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to H-Mode programmable mixer 2.
Set the input to 0 to disable this function.



H-Mode Pmix 2 Output Channel

Modify Constants - 37

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to H-Mode programmable mixer 2.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



H-Mode Pmix 2  Gain

Modify Constants - 38

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for H-Mode programmable mixer 2



H-Mode Pmix 3 Source

Modify Constants - 39

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to H-Mode programmable mixer 3.
Set the input to 0 to disable this function.



H-Mode Pmix 3 Output Channel

Modify Constants - 40

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to H-Mode programmable mixer 3.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



H-Mode Pmix 3  Gain

Modify Constants - 41

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for A-Mode programmable mixer 3.



A-Mode Pmix 1 Source

Modify Constants - 42

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to A-Mode programmable mixer 1.
Set the input to 0 to disable this function.



A-Mode Pmix 1 Output Channel

Modify Constants - 43

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to A-Mode programmable mixer 1.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



A-Mode Pmix 1  Gain

Modify Constants - 44

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for A-Mode programmable mixer 1.



A-Mode Pmix 2 Source

Modify Constants - 45

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to A-Mode programmable mixer 2.
Set the input to 0 to disable this function.



A-Mode Pmix 2 Output Channel

Modify Constants - 46

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to A-Mode programmable mixer 2.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



A-Mode Pmix 2  Gain

Modify Constants - 47

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for A-Mode programmable mixer 2



A-Mode Pmix 3 Source

Modify Constants - 48

Functions:

  • Select source (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the input channel to A-Mode programmable mixer 3.
Set the input to 0 to disable this function.



A-Mode Pmix 3 Output Channel

Modify Constants - 49

Functions:

  • Select output channel (0= X, 1= Aileron, 2= Elevator, 3= Rudder, 4= Pitch)
     

This is used to set the output channel to A-Mode programmable mixer 3.
Set the output to 0 to disable this function.
Yes, the output can be set to the same as the input. 



A-Mode Pmix 3  Gain

Modify Constants - 50

Functions:

  • Adjust gain -100%..100%
     

This is used to set the gain for A-Mode programmable mixer 3.



VTOL/Tandem Control Software General Information     
         

  • The TH-2 synchronizes with the pitch channel (CH-6 on most radios) and expects it to be the last pulse
    (that it "sees") in the data frame sent by the transmitter.  Also, A gyro should not be used on this channel.
     It wouldn't make sense anyhow.
     
  • When setting up the DCP it helps to turn off the cyclic component to visualize it better.  This can
    be done by temporarily setting the gain to zero (0) in the Tech Link modify constants menu.
     
  • When an input gain is set to 100% the pulse data from the TX is used as is and mixed.  At 50%, the pulse
    data from the TX is cut in half and then mixed and so on.  Reducing the gain in the TH-2 when needed,
    like for DCP, is better than doing it in the TX (ATV setting) since this would reduce the overall dynamic range. 
     
  • The gain settings also allow you to balance the amount of servo travel from the contributing channels and
    prevents clamping.  The TH-2 is set to clamp at 0.90 ms min. and 2.10 ms max. to prevent servo damage
    in the event of interference.

     

 

 

Copyright 2006 by Tech Model Products LLC. All Rights Reserved