Old 04-18-2018, 10:36 PM
  #8  
olnico
 
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Just do the same stuff as real size aircraft.
Have the nose wheel partly mixed to the rudder stick for max landing speed deviation allowed ( usually about =-15 degrees ).
The remaining of the travel ( about +-50 to 70 degrees ) should be located on a tiller ( typically a volume knob on the transmitter ).

At typical landing speeds, a deflection of over 15 degrees on the nose tire will just result in a flat. The rubber adhesion will not be sufficient for the cornering action commanded. The higher the landing speed, the smaller the nose tire diameter, the harder the tire rubber, the more noticeable the cornering limitation becomes.
Also, at high speeds the cornering action might over-torque your servo if too weak/ or too much travel is required.

As said above by Raff', a great option is to place a gyro in heading lock on the steering channel and electric brakes.
Our LG15 electric gear controller does exactly this. It has a gyro on the yaw axis only dedicated to the ground operations ( gear extended ).
This has two actions:
1. control the steering servo in heading lock
2. Control electrical differential braking in heading lock.

Point 2 reduces the nose wheel cornering force dramatically for high speed/ small nose wheel equipped airplanes.

https://www.ultimate-jets.net/produc...ear-controller

The other benefit of a gyro equipped gear controller is that you do not have to bother with the gyro gain mixing/ sharing between rudder and steering. Your flight gyro is a different box and completely decoupled from your ground system gyro ( gear controller ). You can easily program completely different gains between the rudder and the steering servo. At the end of the day, this makes sense as they are completely different controls and have a different point of action on the plane ( one is above the roll line, the other one is below the roll line, one has a decreasing action with decreasing speed, the other an increasing action with decreasing speed ).

In practice, assign the steering servo to a separate channel, controlled by a volume knob ( and assigned to a gyro line if willing to do so ). Then mix in a bit of rudder to that channel.

Last edited by olnico; 04-18-2018 at 10:48 PM.
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