At the end of this lesson, you should be able to correctly:
Remember – there is no such thing as a fully autonomous aircraft.
Such an aircraft would not require any human intervention at all to plan and execute a mission.
Aircraft that do require some form of human intervention must be able to communicate with the human – hence the need for a data link.
Most smaller unmanned aircraft have more than one form of data link operating simultaneously – each with its own dedicated function.
Common Components of the Remote Pilot (or Ground Control) Station typically include the following:
A control link is responsible for sending signals from the remote pilot or GCS to the aircraft in order to directly govern the operation of the aircraft.
Feedback signals travel from the aircraft to the GCS to provide location, status, reports and warnings.
Auxiliary functions are controlled from the GCS. (Lights/sirens/dropping devices/cameras).
Examples of command & control links are:
Note: A stable link between the aircraft and remote pilot station is critical for safe operation.
Example of flight critical feedback from a Command & Control Link is the Primary Flight Display (PFD), which shows in-flight information, such as:
There are several commercially available radio transmitter. These commonly have two (2) stick for the pilot’s flight control inputs,
along with a number of toggle switches for additional control inputs, such as:
Commercial RC Transmitters may have different stick layouts. Diagrams below show a Mode 1 and Mode 2 stick layout, which inter-changes pitch and throttle.
Mode 2 more closely resembles manned aircraft controls, which typically has pitch and roll on the same stick. Below is a diagram illustrates stick input with relation to a fixed-wing control.
In addition to flight controls, other optional controls can be added, as dependant on aircraft configuration. These include, but are not limited to:
These additional controls can be configured on as switches on the transmitter or sent as commands directly from the GCS software.
The maximum power we can use to communicate with an unmanned aircraft is set by regulation – we have no choice with this. (Antennae gain is also factored into the regulations!)
Signal strength (received) is NOT just a function of transmitted power – antennae type (including directionality) also has a significant influence on received signal strength – in terms of both the transmitter and the receiver requirements!
Antennas used in commercial UAVs are typically omnidirectional, which is
A Directional Antenna configurations are a series (or array) of dipole antenna, which are arranged in a way that propagates waves in a specific direction.
“Software” typically refers to the off-board program used to operate and monitor the aircraft from a remote station (Ground Control Station Software).
The main functions of a GCS Software is:
This is typically off-board, on the GCS, or an app on a mobile device used to connect with the aircraft.
“Firmware” typically refers to the on-board program and flight-critical component, which governs the aircraft’s low-level control functions.
The on-board firmware interprets these control inputs send from the remote pilot station. The firmware then execute the appropriate flight control surfaces and/or throttle response to achieve the desired control inputs.
Examples below illustrates throttle control of individual motors on a Quad Multirotor configuration, which is typically governed by the on-board firmware.
Software and firmware versioning are typically shown with three (3) or more numbers.
Updates are a method for users to load new software or firmware onto our system:
Key reasons to update are:
Telemetry in the context of UAV operations, is the transfer or communication of data to and from remote points in a field. Telemetry is typically attached to the Ground Control Station, and the aircraft, to allow for communication between the two.
What sort of information do you think can be transmitted?
The cases where telemetry is unreliable:
Similar to Command & Control Links, Payloads can be communicated via:
Payload communication could be:
Examples of payload communications:
Battery charging stations are usually set up to ensure continuous operations during extended flight day