Status : Available

AUTOMATIC LANDING GEAR (ALG)

The automatic landing gear controller costs £25.00

Postage weight 10 gm with futaba connectors 1gm without

Don't forget to add postage from the postage section

DESCRIPTION

Using an IR beam the presence of a surface can be detected by the ALG.

Once the presence of a surface has been detected and the unit has applied some hysteresis the signals to the servo outputs will cycle between states.

The unit is designed to run from a single lipo or a bec output.

The approximate range of the detection is 40cm this can vary slightly with different surfaces and different ambient light levels.

There are two servo outputs that give opposite signals while in the two different states.

Surface present

Servo output A will produce an angle of zero degrees while a surface is present

Servo output B will produce an angle of 90 degrees while a surface is present

Surface not present

Servo output A will produce an angle of 90 degrees while a surface is not present

Servo output B will produce an angle of zero degrees while a surface is not present

The reason for this is that wing mounted servos are usually mounted in opposite orientation and the servo arm needs to reflect that fact for the undercarriage deployment to work correctly.

CONNECTIONS

The unit below is equipped with Futaba style connectors.

There are three servo output connectors, two are connected to servo output B and one is connected to servo output A

For Really lightweight models it is possible you will want to do away with the connectors that are supplied.

For the maximum weight savings you may wish to wire the servos directly to the ALG pcb.

HOWEVER this requires a modicum of skill and the correct type of soldering equipment.

If you feel you need a VERY light system I will be able to offer this service on an individual basis at extra cost contact me to discuss.

MOUNTING

The pcb has a plain back and can be glued to most surfaces.

When mounted the ALG pcb must be at the bottom of the aircraft looking down with nothing obscuring the field of view.

The undercarriage when deployed can not be in the field of view as this would result in the surface detection being fooled into thinking the aircraft had not become airborne.

Using a servo as the retract mechanics it is possible to install one in each wing with an undercarriage leg fixed to the output arm of each.

Some modellers may wish to install only one servo and design a mechanical system around it.

In either case the servos need to be strong enough to withstand the expected loads.

DIMENSIONS

0.4gm without connectors

approx 17mm square

SMALL TRICYCLE SETUP ON INDOOR HELICOPTER

Walkera Dauphin

This is normally a fixed undercarriage but with an ALG unit and some alterations

it can have a fully automatic retractable undercarriage