Emsis — Manual
3. Emsis PFD
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Emsis PFD
Emsis PFD (Primary flight display) consists of electronic units which
work closely together to bring flight information onto graphical dis-
play. The system consists of the following electronic components:
Airu (AD-AHRS and GPS unit) – hereinafter referred to as
AHRS unit – is an inertial navigation unit aided by the GPS
and pressure sensors. AHRS provides attitude, position and
velocities. AHRS unit is hidden inside Emsis PFD unit.
Emsis unit – presents all relevant information that appears on
the CAN bus in a pilot friendly form on LCD screen. Most of
this manual describes how to access, read and interact with the
Emsis display.
Emsis PFD unit uses state of the art MEMS
sensors to read various
physical quantities. Since all sensors are solid state, it has no moving
parts. This means it has fewer problems with fatigue and ageing.
The following MEMS sensors are used in the Emsis PFD system:
The angular rate sensors, also known as gyros, are used in the
attitude calculation. The angular rates are integrated in time
in order to predict new attitude from the old one. We could
say that they give short-time attitude prediction. They are also
used in gravity vector calculation.
The acceleration sensors are measuring apparent gravity vec-
tor. The true gravity vector is calculated assuming coordinated
flight and readings from the other sensors (velocity and angular
rate sensors). The ball slip indicator is directly obtained from
the acceleration sensors.
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MEMS - micro-electromechanical systems, a.k.a micro machines, a.k.a micro
systems technology.
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Kanardia
2021