Practical Exercise Autonomous Aerial Search Vehicle (AASV)

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Practical Exercise Autonomous Aerial Search
Vehicle (AASV)
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Autonomous Aerial Search Vehicle (AASV)

• Autonomous Aerial Search Vehicle (AASV) is in
  short term a model airplane with a programmable
  controller onboard programmed to control and
  steer the airplane based on information received
  by a GPS. AASV also have a ground based part
  which send and receive information to and from
  the airplane, and also have the opportunity to
  override the programmed controller onboard the
  airplane and take control.
• The AASV will be restricted to a flying platform
  capable of flying according to a predefined
  route. Take off and landing will be done
  manually, autonomous flight will only commence
  when the aircraft is at a predefined minimum
  altitude and manual flight must be resumed before
  landing.
• The Autonomous Aerial Search Vehicle (AASV) can
  be divided, in the airborne systems part and the
  ground based systems part.

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Autonomous Aerial Search Vehicle (AASV)

• Both the onboard Eyebot controller and the ground
  based laptop shall be able to autonomously fly
  the aircraft according to a predefined route
  using the input from the GPS.
• When the onboard controller is controlling the
  aircraft both GPS data and control signals shall
  be reported to the ground based system who
  presents this information on screen as well as
  logging it.
• Whether the airborne system or the ground based
  system is controlling, the aircraft shall be
  controllable through the laptop interface.
• It shall also be possible to control the aircraft
  using a control stick connected to the laptops
  RS-232 port. In case of manual control the
  signals from the control stick shall be collected
  by software on the laptop, processed and sent to
  the Eyebot controller through the GSM connection.
  The Eyebot process these data and move servos
  accordingly.
• It shall be possible, using the control stick, to
  select between autonomous and manual flight.
• Since navigation in the air can be dangerous, as
  it can crash, the AASV must be robust with regard
  to both software and hardware failures. It must
  be able to handle failures and be able to operate
  in another state (both autonomous and manual).

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Autonomous Aerial Search Vehicle (AASV)

• We will mainly look at the airborne system. The
  airborne system consists of the following
  technical equipment (excluding the airplane
  itself)
• Eyebot Robot controller
• GPS
• GSM modem
• Servos to move control surfaces and throttle
• 7.2 volt battery to power Eyebot
• 6.0 volt battery to power servos
• 12.0 volt battery to power GPS and GSM
• Various cables and switches

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Airborne system

• The following functions are central to the
  purpose and operation of the airborne system
• The system shall be able to autonomously fly the
  aircraft according to a predefined route using
  the input from the GPS.
• The system shall be able to send GPS data and
  control signals to the ground based system when
  the onboard controller is controlling the
  aircraft, using a GSM transmitter.
• The system shall be able to receive control
  signals from the laptop through the GSM
  connection.
• The system shall be able to process the control
  signals from the laptop through the GSM
  connection and move servos accordingly.
• This system is also going to make sure that
  nothing critical will happened.

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Airborne system

• Stakeholders
• The client.
• The software developers of the AASV.
• Future users of the AASV.

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Components

• GSM modem
• This GSM modem is communicating with the
  surrounding GSM network, and is used to establish
  communication with the ground while the plane is
  flying. This part is interacting with the Eyebot
  using RS-232 (serial) communication. The GSM
  modem is essential when it comes to sending and
  receiving data to and from the ground based
  system.
• All communication between the airborne system and
  the ground based system will go through the GSM
  modem
• GPS
• The GPS will register where the plane is in a
  three dimensional form (longitude, latitude and
  altitude). The GPS will also register the
  airplanes speed and course (North, East, West,
  South).
• Latitude (breddegrad)
• Longitude (lengdegrad)
• Altitude (høyde)

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Components

• RS-232
• The communication between the Eyebot and GPS and
  between the Eyebot and GSM-modem is based on the
  RS-232 serial interface communication.
• Servos
• Based on Eyebot output the servos change its
  position, which makes the airplane turn, change
  height and speed.
• Eyebot
• This is the computer (CPU) in the airplane
  system. This part has the responsibility of
  controlling everything that is happening in the
  plane. It controls the incoming data from the
  GPS, the outgoing and incoming data from the GSM
  and finally it runs the servos that control the
  airplane (rudder, elevator and throttle). This
  component also has a microphone attached to it.
  This can be used to monitor different sound.

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Components

• Servo switcher
• A switch which decides if it is the servo
  positions from the RC receiver or the Eyebot that
  will be chosen. The switch is controlled by the
  RC receiver, which is controlled by the main
  controller..
• RC Receiver
• Receive servo signals and control signal from the
  main controller on ground.

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Definitions, Acronyms and Abbreviations
Word Explanation
AASV Autonomous Aerial Search Vehicle
CPU Central processing unit
GSM Global System for Mobile communications
GPS Global Positioning System
Eyebot General purpose robot controller
Servo A mechanical unit that moves a physical component
RS-232 Serial interface communication
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FMEA

• FMEA selects the individual components or
  functions within a system and investigates their
  possible modes of failure.
• It then considers possible causes for each
  failure mode and assesses their likely
  consequences.
• The effects of the failure are determined for the
  unit itself and for the complete system, and
  possible remedial actions are suggested.

• For hver komponent/funksjon identifiseres altså
• alle mulige feilmåter (feilmodier),
• mulige årsaker til hver feilmåte,
• mulige konsekvenser, både lokalt og for systemet
  som helhet, av hver feilmåte,
• mulige risikoreduserende aksjoner.

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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H1.1 GSM-modem (exchange data between the ground based and the airborne system).
H1.2 GSM-modem (exchange data between the ground based and the airborne system).
H1.3 GSM-modem (exchange data between the ground based and the airborne system).
H1.4 GSM-modem (exchange data between the ground based and the airborne system).
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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H2.1 GPS (register where the plane is in a three dimensional form (longitude, latitude and altitude).
H2.2 GPS (register where the plane is in a three dimensional form (longitude, latitude and altitude).
H2.3 GPS (register where the plane is in a three dimensional form (longitude, latitude and altitude).
H2.4 GPS (register where the plane is in a three dimensional form (longitude, latitude and altitude).
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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H3.1 Eyebot-controller (controls the incoming data from the GPS, the outgoing and incoming data from the GSM and finally it runs the servos that control the airplane (rudder, elevator and throttle). This component also has a microphone attached to it)
H3.2 Eyebot-controller (controls the incoming data from the GPS, the outgoing and incoming data from the GSM and finally it runs the servos that control the airplane (rudder, elevator and throttle). This component also has a microphone attached to it)
H3.3 Eyebot-controller (controls the incoming data from the GPS, the outgoing and incoming data from the GSM and finally it runs the servos that control the airplane (rudder, elevator and throttle). This component also has a microphone attached to it)
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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H4.1 Servos switch (decides if it is the servo positions from the RC receiver or the Eyebot that will be chosen)
H4.2 Servos switch (decides if it is the servo positions from the RC receiver or the Eyebot that will be chosen)
H4.3 Servos switch (decides if it is the servo positions from the RC receiver or the Eyebot that will be chosen)
H4.4
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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H5.1 Servos (change the position of the airplane)
H5.2 Servos (change the position of the airplane)
H5.3 Servos (change the position of the airplane)
H5.4
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ID Unit (function) Failure mode Possible cause Local effects System effects Remedial action
H6.1 RC receiver (receive servo signals and control signal from the main controller on ground)
H6.2 RC receiver (receive servo signals and control signal from the main controller on ground)
H6.3 RC receiver (receive servo signals and control signal from the main controller on ground)
H6.4