WATTS INNOVATIONS PRISM R.P.A.S., Flight Manual

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PRISM FLIGHT MANUAL
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This chapter deals with the primary functions of the flight control system. The open source
ARDUCOPTER
firmware provides a fully customizable, feature rich autopilot system for
PRISM. The flight controller has been pre-configured by WATTS INNOVATIONS to enable
the operator to complete most tasks in a safe and efficient manner. A more in depth study
of the autopilot system and features may be conducted using the online resources at
https://ardupilot.org/copter
It is important to note however, that PRISM utilizes a custom Arducopter firmware.
This means that it should not be updated to a standard Arducopter firmware, as this will
break all of the intuitive features found within PRISM.
Updating to a stock Arducopter
firmware will void your warranty.
Guidance, navigation, and control are provided by Pixhawk CUBE flight controller system.
Sensors in the CUBE include a triple-redundant, 6-axis inertial measurement system; GPS/
GNSS receiver and magnetometer (compass); and dual barometric pressure sensors for
detecting aircraft altitude.
This system allows for operation in 5 primary flight modes , and multiple Failsafe modes .
The pilot can change flight modes with the three-position FLIGHT MODE switch on the
remote control unit, and the mode of each position may be defined in the WattsQGC app.
When operating through the mobile device interface, the pilot will have the ability to select
from a variety of other flight modes as required.
This manual deals with the 5 primary modes that can be selected using the handheld radio
control unit only. Each mode is discussed in turn as follows.
It should also be noted that the user may choose to use STABILIZE flight mode, which is a
self leveling mode (for both the roll and pitch axis), where the throttle is a direct correlation
to the % of throttle given by the user. Pilots must be extremely careful when arming and
taking off in STABILIZE mode. In addition, the RPA may either “jump” or “drop” up to 3m
when transitioning from STABILIZE to ALTHOLD mode. Flight in STABILIZE mode is not
recommended but can be useful in the hands of a skilled pilot.
ALT HOLD mode is the base flight mode of this PRA, and provides the most manual
control over the aircraft. In this flight mode, the aircraft uses the onboard sensors to only
stabilize its attitude and altitude.
Pitch and roll are commanded by manipulating the respective control sticks.
7.4 FLIGHT CONTROL SYSTEM
7.4.1 ALTITUDE HOLD