The home-build project described below is a force feedback flight yoke
that can be used with MS FS9/X and X-Plane flight sims. The
FFB yoke provides variable
control feel generated by electric motors built into the
flight controls. This makes the flight yoke feel much more
realistic - its forces and vibrations vary with the varying
phases of the flight and ground operations.....
It is an
advanced level project and requires good mechanical
and electrical build skills.
This is a project for the flight sim enthusiast; as a
working estimate the project will cost about UKŁ800 (+
control wheel) to complete (depending on motor, encoder
and other component prices.
The project follows the same pattern as other
flight sim projects on the site - you will find detailed
plans, essential software and key bits of electronics below.
Obtaining the other parts and materials needed for the
project is up to you.
The main elements of the project
are:
PLEASE read the above documentation
carefully if you are interested in building the DIY CL Yoke
or your own flight controls using the CL system.
The force response of the yoke
varies with flight conditions so that changes in airspeed,
trim settings etc cause the feel of the controls to change -
similar to the behaviour of real aircraft controls.... This makes for force feel much more like real flight controls.
The
force levels produced are also much higher than on conventional FFB joysticks.
The default system set up will produce single handed
aileron control forces up to 4.25 kgf (~9 lbf) and elevator
forces up to 9 kgf (~20 lbf).
Larger forces can be generated
but would require the transmission ratios to be increased.
The yoke's range of travel is +/- 90 Deg
on the aileron axis and 155 mm on the elevator axis.
NEW
CL_SPU_USB + BLDRV3 Drivers |
BFF CL Software |
The force components generated by the control
loader system
include:
-
Airspeed dependent
aerodynamic loading (centring forces proportional to
control surface displacement and airspeed)
-
Adjustable aerodynamic force gains
(equivalent to adjustable control surface area)
-
Angle of attack (alpha and beta)
effects (eg for longitudinal stability response)
-
More realistic trim behaviour (independent
of simulator trim system, controls can be force trimmed in any
position)
-
Control surface static & dynamic
weight effects (aircraft acceleration effects)
-
Prop-wash effects
-
Engine vibrations (vary with power &
rpm)
-
Runway vibration effects (vary with
runway speed)
-
Stall buffeting effects (frequency
and amplitude definable - eg stick vibration type
behaviour)
-
Damping and friction adjustments (-ve
gains definable)
Auto Pilot following
Note that the plans do not
include the control wheel (yoke) - choice of which is likely to be a
matter of personal preference or dictated by the particular
cockpit build. The plans show a 25mm
outside diameter hollow tube to which you must secure your
wheel. Please make sure your choice of wheel is strong
enough to carry the forces (some plastic yokes designed for
light spring loading may struggle with the force levels).
FFB
Yoke Mechanical Build
Yoke Construction |
The mechanical build is described in the pdf
plan set available below. The plans cover component detailed
dimensions, bought component details, and build/assembly
procedures. The design has an unenclosed mechanism and is
primarily intended to be built into a flight cockpit. For
desktop-use you should provide covers for the mechanism.
The pdf document is password protected - the
password is: yoke
DIY FFB Flight Yoke
Plans |
The yoke construction is fairly simple in
principal - but needs to be built accurately. The aileron drive motor, wheel tube and control
wheel (not included) are mounted on a travelling carriage, which itself is
mounted on low friction linear guides and linear ball bushings. The
control wheel tube is mounted in needle roller bearings on
the carriage. The
carriage is driven by the elevator motor via a toothed belt
loop. The elevator motor is mounted on the base structure of
the yoke at the rear.
Each movement axis is loaded by a
single 3 phase BLDC motor (fitted with 360 cpr quadrature
encoder). The motors are specified in the drawings. An
important characteristic is their sinusoidal
back EMF which enables
very smooth response to the sinusoidal commutation voltages from
the purpose designed BFF BLDRV3 drivers.
BLDC motors - used
with specialised controllers.. |
The BLDC motors are sized
to allow simple toothed belt torque
transmissions to be used whilst still providing good levels of force
output. These belt drives are easier to build than spur
gearing and are fairly tolerant of slight misalignments and
positioning errors likely to be found in DIY constructions.
The force levels are such that
at the higher levels
one handed
operation of the yoke becomes quite uncomfortable quite
quickly if the control is displaced or untrimmed. The yoke needs to be
secured to a fixed base otherwise it
will move under the generated loading. At full load with 24V
supply the elevator loading is about 9 kgf (20 lbs), one
handed aileron operation at full load requires about 4.25 kgf
(9 lbs). These forces are typically with the controls fully
displaced during a flight manoeuvre, force levels during normal flying conditions are
much lower than this off course.
Provision is made for fitting potentiometers to report
the control position.
NOTE the plans do NOT include details of the
control wheel - builders must source their own. The hollow
yoke tube shown in the design is 25mm outside diameter.
Wiring for any buttons on the wheel can be routed through
the yoke tube.
A number of videos clips of the prototype in operation are on
Page 2.
MOVIE CLIPS ON PAGE 2
Drawing Set Revision History
29/9/11 - Sheet S001-2 raised to R2 - corrected item 2
(front plate) width.
19/9/11 - Sheet A004-1 raised to R2 - corrected item 24
(belt) length.
© This site is
copyrighted, If you'd like more information or have any
comments please contact me at