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BOGEY Hexacopter Build Manual
Virginia Tech
David Jensen Dept. of Industrial and Systems Engineering
Virginia Tech, Blacksburg, VA 24060 [email protected]
Haseeb Chaudhry Dept. of Mechanical Engineering
Virginia Tech, Blacksburg, VA 24060 haseeb7vt.edu
Tomonari Furukawa
Dept. of Mechanical Engineering Virginia Tech, Blacksburg, VA 24060
Abstract
The objective of this manual is to serve as a step by step tutorial for the replication of the
BOGEY Hexacopter as produced by Team VICTOR from Virginia Polytechnic Institute and
State University to fulfill the challenges from the MBZIRC 2017 Competition.
This will require the replication of several customized wiring components, identifying elements of
the wiring network, and to safely and expediently resolve potential problems and damages that
can occur during flight.
The BOGEY multirotor unmanned aircraft is designed to survive above average wind speed
conditions averaging 20mph while maintaining stability for operations involving visual object
detection. Electrical and computational elements were assembled for the further application of
autonomous flight.
Assembly and Organization
The BOGEY style aircraft was integrated into an already existing commercially available UAV
platform to reduce task complexity. It is therefore assumed that instructions for the physical
frame are already established and details on the construction of the multirotor will be provided
beginning at the completion of this step.
This guide will entail physical assembly adjacent to instructions for electrical components as
they become relevant to the operation at hand.
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Index
Assembly PG
1 Frame Body 3
1.1 Tarot T810 Frame 4
1.2 Retractable Landing Gear and Plate Adapter 5
2 Power Distribution Board and Internal Wiring 6
2.1 Power Distribution Board 7
2.2 Soldering ESCs and Preparing Internal Wiring 11
2.3 Attaching the PDB 14
3 Rail Components 17
3.1 Forward Mount Plate 19
3.2 Rear Mount Plate 22
3.3 UBEC Wiring and Rail Mounting 25
4 Control Elements; Onboard Computer Attachment and Wiring 27
4.1 Pixhawk PX4 Flight Control Board Mounting 28
4.2 Pixhawk PX4 Flight Control Board Wiring and Control Elements 29
5 Top Plate; TX1 Onboard Computer Modifications 31
5.1 Delrin Top Plate Components 32
.5.2 TX1 Onboard Computer Attachment and Wiring 35
3.6 Project Overview and Operation 37
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1 Frame Body
1.1 Tarot T810 Frame
1.2 Retractable Landing Gear and Plate Adapter
Necessary Tools and Materials
12V BOSCH Impact
Driver
{Included Allen Key Bits: 3mm, 2.5mm,
2mm, 1.5mm}
Assorted Allen Keys
{3mm, 2.5mm, 2mm, 1.5mm}
Pliers
Threadlocker
Tarot TL96030
Retractable Landing Gear
Tarot T810 Frame
w/Associated Parks Kit
Tarot 16 in.
Extended Rails
Acetal Delrin Sheet
Flathead Screw M3 10mm Black-Oxide
Steel (x8)
Socket Head Screw M3 40mm
Black-Oxide Steel
(x8)
M3 Nylon Locknut
(x8)
M3 Split Lock
Washer
(x8)
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1.1 Tarot T810 Frame
Instructions for the original frame body assembly are included in the purchase of the original Tarot
aircraft. Following the provided instructions, the frame will be completed with the following altercations:
The original frame body included stationary landing gears for simple contact landing. These will
be discarded and replaced with a set of remotely operated retractable landing gears. The addition
of retractable gears will remove a moment created by crosswind and remove the landing feet out
of the field of view for the onboard camera when upright.
The original frame includes a metal socket brace for securing the static landing gear joint
Replace the original aluminum socket with a flat metal brace which can be found in the set for the
retractable landing gear
Space is needed for the plate modification to accommodate this set of
retractable landing gears. This will lead to a horizontal offset from the center
of the aircraft so that the aircraft can carry a more compact payload.
Replace the original socket head screws at the stationary arm
attachment points with the listed 40mm socket screws with additional M3
split lock washers (Figure 1.1-1). This will later ensure that the flathead
screws are not causing warping within the later stage Delrin adapter plates.
Figure 1.1-1
Figure 1.1-2: Retractable Landing Gear Components
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1.2 Retractable Landing Gear and Plate Adapter
A simple STL model was converted for laser cutting on a UNIVERSAL M-360/V-460 Laser Engraving and
Cutting System using Acetal Delrin of 0.06” thickness.
The laser-cut Delrin sheet is then attached to the retractable landing gear (red) where the remaining ports
will substitute for the mounting ports to the frame body (Figure 1.2-3). This is done using the 10mm
flathead screws to remain comparatively flush with the surface of the aircraft. The surface seal will not be
perfect to the airframe, but this is not critical to the operation or integrity of the component.
Avoid excessive tightening or the Delrin plate will break. It will
be noted that more resilient materials could be used. If this is
done however, any potential in-flight error leading to a crash
will transfer most all impact stress to the brace adjoining the
landing gear. It was therefore decided to keep the Delrin
plates as they were easier to replace due to a potential
mishap than replacing the entire retractable landing gear leg.
The landing gears can be raised and lowered by manually
contacting a small battery. Ensure that this is below 3S or the
applied voltage may damage the small motor (Figure 1.2-4).
Lowering the landing gears will make future steps more fluid.
Figure 1.2-1
Figure 1.2-2
Figure 1.2-4
Figure 1.2-3
Figure 1.2-5
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2 Power Distribution Board and Internal Wiring
2.1 Power Distribution Board
2.2 Soldering ESCs and Preparing Internal Wiring
2.3 Attaching the PDB
Necessary Tools and Materials
Soldering Station
Wire Strippers
Snips
Pliers
Gryphon Octocopter Power Distribution Board (PDB)
Unparalleled Electronics 4-14S Power Supply (60V
Max)
Turnigy 5/6A Switching BEC 2-10S (8-40V)
Afro HV 20A Multirotor ESC (3-8V)
(x6)
3.5mm Male/Female Bullet Connectors
(x30 Male) (x12 Female)
Servo Wire Connectors
(x6)
7mm AS150 Self-Insulating
Connectors
(x2 Pair)
Tarot 5008 Brushless
Motor (340kv)
(x6)
16 AWG Silicon Wire
Red/Black
10 AWG Silicon Wire
Red/Black
22 AWG Servo Wire
Zip Ties
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2.1 Power Distribution Board
The Gryphon PDB was selected due to its high voltage tolerance and the space to add elements as
needed. Due to the high voltage from two 6S batteries that will pass through the power boards, extra
attention should be made to ensure the security of board connections. Additional heat-shrink may be
required to properly protect joints from potential contact with other adjacent components.
The Gryphon PDB consists of two open plates for
POWER and GROUND (Figure 2.1-1). Broken or
improperly connected components can therefore be
more readily identified and repaired prior to flight.
Connections can become separated or unseated
due to mishandling prior to reassembly or following
rough operations.
The Gryphon PDB package contains 16 of the 30 male bullet connectors that will be required in addition
to a set of spacers that will separate the pair of plates from the frame body.
The Power Supply element will be threaded through the available ports though the Gryphon
plates. The 14S Power Supply used 10AWG wire cable, and will require a through-hole solder
joint at one of the available Battery ports in the POWER PDB plate.
The input line opposite to the direction of power flow (indicated by demarcation on the 14S Power
Supply) will be threaded through the adjacent port (Figure 2.1-2). This will thread through the
nearest port on the GROUND plate in the following steps.
The 14S Power Supply will be suspended over the PDB cavity. This will be done to accommodate
for future steps when the PDB is seated to the body of the aircraft.
Figure 2.1-1
Figure 2.1-2
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Using AS150 connectors and two lengths of black 10AWG wire approximately 6in. long, solder two
adjacent through-hole Battery ports on the Gryphon PDB GROUND plate.
Ensure that AS150 socket joints are used for this step
The 14S Power Supply has two inputs from each POWER and GROUND. The following step will
combine each twin outputs with a third join from the 5/6A Switching BEC. This output connection
will lead to a single POWER/GROUND servo connection for the Pixhawk PX4 Aux2 input port.
Solder POWER and GROUND inputs leads of the 5/6A Switching BEC to the respective plates on the
Gryphon PDB labelled BEC/AUX (Figure 2.1-5).
Figure 2.1-3 Figure 2.1-4
Figure 2.1-5
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Solder the POWER and GROUND input leads of the landing gear controller to the respective plates at an
available surface-join solder locations of the Gryphon PDB (Figure 2.1-6). This location will later
determine the position of the landing gear on the aircraft during the later mounting phase.
Connect the two Gryphon plates together via the provided threaded nylon spacers. The POWER lead for
the 14S Power Supply should weave through the GROUND plate to an unstrained position.
Prepare the POWER lead joints using solid male AS150 connectors with approximately 6 in. of
red 10AWG high flex electrical wire (Figure 2.1-7).
Figure 2.1-6
Figure 2.1-7
Figure 2.1-8
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These POWER leads can be woven together using either spare solder or spare wire (24 AWG
or below). Ensure that the leads are properly woven together and dipped in flux prior to
soldering to maintain a well-seated join. Prepare the lead from the 14S Power Supply with
shrink-wrap prior to joining (Figure 2.1-9).
Ensure that the Turnigy 5/6A Switching BEC is pulled through the aperture on the Gryphon PDB. The
POWER and GROUND leads should appear approximately the same length to be later swayed to the
side for future battery connection. This method will reduce the stress at the primary solder joints due to
pull or vibration during prior to and during flight.
The result for this section should resemble (Figure 2.1-10) above.
Figure 2.1-9
Figure 2.1-10
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2.2 Soldering ESCs and Preparing Internal Wiring
The hollow carbon fiber arms of the Tarot T810 frame have ports that allow internal wire to be threaded
through. This may require a set of pliers to appropriately grasp at the wire leads through the apertures.
The lengths of POWER, GROUND, and servo wires can be approximated for each arm – with the
understanding that the two stationary arms will require less wire length than the four folding arms. These
lengths should also be long enough to safely reach the bullet-connector ports on the Gryphon PDB
without risk of tear in the wire tubing that could expose power wires to the carbon fiber surface.
If electrical current is incurred into carbon fiber the surface may begin to fray apart, creating a potential
health hazard of carbon-fiber dust inhalation.
Approximately 2 in. of slack should be given to the four folding arms to allow for changes in pull when in
the stored position. The POWER and GROUND leads will be socketed to the available outlying six female
bullet-connector ports on the Gryphon PDB.
Cut and solder male and female bullet connectors on the respective ends of the power and
ground wires prior to the final threading.
Prior to the final threading, ESCs will be soldered directly to the servo wire. This will prevent the
ESC wire separating from the servo wire, which might otherwise occur with single pin connection.
The ESC has signal and ground wires that will be transferred to the servo wire (Figure 2.2-2).
Figure 2.2-1
Figure 2.2-2
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Ensure that the wires are threaded through the outer port in the motor mount prior to soldering
The power lead from the servo wire can be closed off since it will not be used. This can be done
by extending shrink-wrap over the lead end and quickly pressing the hot end together to form a
seal. This will prevent frayed or open ends in the unused wire. An alternate method would involve
the removal of the yellow signal wire and assigning the red output lead to the signal input when
assigning motor inputs to the Pixhawk PX4 servo inputs (Figure 2.2-3). However, for color
consistency this method will be used.
The Tarot kit may contain wire sheath and a tooth for threading wire through it. It is advised to thread the
servo wire starting from the outer arm and pulled through the aperture first, then thread POWER and
GROUND wires within a wire sheath leading to the outer arm.
The result for this section should resemble (Figure 2.2-5) above.
Figure 2.2-3 Figure 2.2-4
Figure 2.2-5
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Motors mounts provided with the Tarot T810 body frame should be levelled and mounted on the extended
mount arms. Minute imperfections in the angle of the motor mount are not critical as they will be adjusted
automatically by the onboard flight control board.
Prior to mounting the motor, make thread locker should be added to all motor mount screws.
Motor mount screws are most prone to vibrate out of position due to vibration, and failure on any
individual element can result in a crash if steps are not taken to ensure that everything is in order.
Power and servo wires can be threaded through the port on hollow mount arms to the ESC
The ESC can be attached to the motor mount with a large zip tie following wiring
The six Tarot 5008 340KV motors should be mounted with thread locker and the provided 8mm M3 bolts.
Figure 2.2-6 Figure 2.2-17
Figure 2.2-8 Figure 2.2-9
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2.3 Attaching the PDB
The Gryphon PDB will be mounted directly between the retractable landing gears below the rotorcraft.
The 10AWG battery leads should be situated on either side of the aircraft (Figure 2.3-1).
The 5/6A BEC should have enough slack to pull through the aperture to be stored within the frame cavity.
This element will precede the 14S Power Supply which will rest within the aperture after some effort
(Figure 2.3-2).
Figure 2.3-1
Figure 2.3-2
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If POWER and GROUND wires were appropriately trimmed, as they are attached to the Gryphon PDB the
tension should lightly hold it in place (Figure 2.3-3). Depending on your preference and how much wire
slack you have, the 16WG power and ground wires can be woven through or even below the main
aperture in the Gryphon PDB; if they reach available bullet connections on their respective plates.
The placement and mounting
process of the PDB reduces the
potential of contact with the carbon
fiber frame without demanding
additional materials
If previous wires were properly
pruned, there should not be
significant tension on the bullet
connector joints
The ESC lead wires will serve
the additional purpose of stabilizing
and forcing the Gryphon PDB to
the aircraft frame
The Gryphon PDB will not rest with perfect symmetry to avoid conflict with the retractable landing gears.
The Landing Gear Controller should be mounted beneath the Tarot T810 frame with double-sided tape.
The location will be arbitrary given the location of the previously mentioned joins provided the landing
gear leads can reach the controller (Figure 2.3-4).
Figure 2.3-3
Figure 2.3-4
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As the aircraft is rotated into the standing position, the Gryphon PDB should be lightly suspended by the
power and ground cables against the bottom plate of the T810 frame. Additional measures may be used
to secure the PDB such as zip ties, provided that the frame is levelled against the base of the aircraft and
does not have the potential to contact the carbon-fiber body.
The 5/6A BEC is then secured into the center cavity of the Tarot T810 frame. All servo wire connections
should be oriented towards the rear of the aircraft to connect to the Pixhawk PX4 outbound connections
(Figure 2.3-5).
Primary power elements of the BOGEY Hexacopter are now completed.
Figure 2.3-5
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3 Rail Components
3.1 Forward Mount Plate
3.2 Rear Mount Plate
3.3 UBEC Wiring and Rail Mounting
Necessary Tools and Materials
12V BOSCH Impact Driver {Included Allen Key Bits:
3mm, 2.5mm, 2mm, 1.5mm}
Assorted Allen Keys {3mm, 2.5mm, 2mm,
1.5mm}
Pliers
Threadlocker
Fisheye Lens 1080P USB2.0
170 Degree Camera
Holybro PX4FLOW v1.31 Camera
ELP-USB500
W04AF-60 Camera
LIDAR-Lite v3
GoPro Gimbal
RP-SMA Extension
Cable (8inch)
(x4)
WIFI Antenna
915MHz Antenna
Tarot TL96014 T810 Mounting Rail
Tarot T810 Battery
Mount Plate
(x2)
Tarot Rail Damping Joints
(x16)
Velcro Tape
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Unthreaded Spacer 6mm 25mm Nylon
(x12)
Tarot TL8X002 Auto
Landing Gear Controller
Transceiver Telemetry Radio 500mW 433Mhz
Zip Ties
Socket Head Screw M2.5 30mm Black-Oxide Steel
(x12)
Socket Head Screw M3
8mm Black-Oxide
(x8)
M2.5 Nylon Locknut
(x4)
M3 Nylon Locknut
(x8)
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3.1 Forward Mount Plate
The forward mount plate is designed to hold Fisheye Camera, PX4 Flow Camera, and LIDAR Lite V3. This
plate model utilizes lasercut acetal delrin, but other materials are acceptable.
The Fisheye Lens camera package includes 4Pin Micro JST to USB cable. It is advised that this cable is
attached to the rear camera prior to mounting it to the Forward Plate. If desired, it can be further secured
with silicon adhesive.
The Fisheye Lens camera is mounted using 25mm Nylon spacer, 30mm M3 socket head screws
to offset the camera; providing visible clearance above the PX4 Flow camera and LIDAR sensor
(170deg lens).
Figure 3.1-1 Figure 3.1-2
Figure 3.1-3 Figure 3.1-4
Figure 3.1-5
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The PX4 Flow camera package includes a pico4 connection wire and its own nylon spacer set to offset the
camera from the Forward Plate (Figure 3.1-7).
The PX4 Flow Camera is mounted such that the PIC4 and PICO6 connections are accessible
from the rear
The LIDAR Lite V3 connected directly to the Forward Plate via 8mm M3 socket head bolts (Figure 3.1-9).
SMA cable extensions can be attached for later mounting WIFI antenna for the TX1 computer
Figure 3.1-6
Figure 3.3-5
Figure 3.1-7
Figure 3.3-5
Figure 3.1-8
Figure 3.1-8
Figure 3.3-5
Figure 3.1-9
Figure 3.3-5
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The LIDAR package includes a mRo 6-Pin JST-GH cable connection. This single wire chain will need
to transition into two servo inputs to the Pixhawk PX4 to translate LIDAR data.
− 1− 2− 3− 4− 5− 6
Begin by removing wires 4 and 5 from (Figure 3.1-11) as they will not be needed
→ 3
→ 𝑃𝑖𝑥ℎ𝑎𝑤𝑘 𝐴𝑈𝑋5
Using Input Wire 3 and a 6in. strand of servo wire, solder a triple-joint with a 470mOhm resistor
and the ground wire of the servo connection. This servo pin connection will connect to the
Pixhawk AUX OUT 5 (Figure 3.1-12)
→ 6→ 1→ 2
→ 𝑃𝑖𝑥ℎ𝑎𝑤𝑘 𝐴𝑈𝑋6
Using Input Wire 1, 2, and 6, translate the connections to a 6in. strand of servo wire. This servo
pin connection will connect to the Pixhawk AUX OUT 6. It is advised to shrink wrap both wires
together to maintain wire cleanliness. As before with ESCs, insulate the unused power line from
the servo wire (Figure 3.1-13).
Figure 3.1-10
Figure 3.3-5
Figure 3.1-11
Figure 3.3-5
Figure 3.1-12
Figure 3.3-5
Figure 3.1-13
Figure 3.3-5
Figure 3.1-14
Figure 3.3-5
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3.2 Rear Mount Plate
The GoPro 3-Axis Gimbal package includes two plates, one of which will be mounted to the Rear Plate.
Use an allen wrench to secure the plate with 8mm 3M socket head screws and M3 Nylon bolts
After the base plate is mounted, attach the 3 Axis Gimbal
Using an allen key is advised to bend the provided dampeners into place. Make sure to use a
wider allen key tool to not puncture the rubber (Figure 3.2-4).
Figure 3.2-1
Figure 3.3-5
Figure 3.2-2
Figure 3.3-5
Figure 3.2-3
Figure 3.3-5
Figure 3.2-4
Figure 3.3-5
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Weave the JST connector associated with the gimbal through the nearest ball dampener
The Rear Mount Plate has ports at the dampeners for wires to be pulled through
This will later be connected to an associated BEC for power
SMA cable extensions can be attached for later mounting 915MHz antenna for the RFD900+ Modem.
Figure 3.2-5
Figure 3.3-5
Figure 3.2-6
Figure 3.3-5
Figure 3.2-7
Figure 3.3-5
Figure 3.2-8
Figure 3.3-5
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The USB500 pinhole camera is mounted using a simple 3D printed cavity to mount it properly to the
three-axis gimbal (Figure 3.2-9).
Other means of mounting can be used to accommodate alternate cameras or platforms. This iteration
represents one of the most rapid method of integrating direct camera visual software to the TX1
Computer referenced in later sections of this assembly manual.
Figure 3.2-9
Figure 3.3-5
Figure 3.2-10
Figure 3.3-5
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3.3 UBEC Wiring and Rail Mounting
The final product utilizes two Quanum UBECS
Power to TX1 Computer
Power to GoPro Gimbal
The provided UBECs have two outputs: one JST male, and one Servo male.
For the first UBEC the second set of output cables can
be sealed off with spare heat-shrink. The other output pair
should be soldered to a DC plug, which will later power the
TX1.
The second UBEC outputs will remain as they are. The
adjoined JST connector will be used to power the GoPro
Gimbal. The Servo output will be connected to the Pixhawk
RC IN input.
Mount the battery plates and the Forward and Rear Mount Plates to the mounting rail.
Ensure that there are four mount positions that are facing upward to attach to the frame.
The bullet connector inputs should connect to the two remaining vacant ports of the Gryphon PDB.
The result for this section should resemble (Figure 3.3-3) above.
Figure 3.3-1
Figure 3.3-5
Figure 3.3-2
Figure 3.3-5
Figure 3.3-3
Figure 3.3-5
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Using 8 of the 30mm screws and 25mm spacers, attach the mounting rail.
The mounting rail is lowered to provide clearance for the retractable landing gears (Figure 3.3-4).
Figure 3.3-4
Figure 3.3-5
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4 Control Elements; Onboard Computer Attachment and Wiring
4.1 Pixhawk PX4 Flight Control Board Mounting
4.2 Pixhawk PX4 Flight Control Board Wiring and Control Elements
Necessary Tools and Materials
12V BOSCH Impact Driver {Included Allen Key Bits:
3mm, 2.5mm, 2mm, 1.5mm}
Assorted Allen Keys {3mm, 2.5mm, 2mm,
1.5mm}
Pliers
Threadlocker
3DR Pixhawk PX4
FrSKY 8XR 8/16CH Telemetry
Pixhawk PX4 Buzzer
Acetal Delrin Sheet
Nylon 6/6 Threaded Hex
Standoff 25mm
(x4)
Nylon 6/6 Threaded Hex Standoff 20mm
(x4)
Nylon 6/6 Threaded Hex
Standoff 12mm
(x4)
M3 Nylon Locknut
(x4)
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4.1 Pixhawk PX4 Mounting
The four primary-upper mounting holes will be utilized for mounting the Pixhawk PX4. This will be done
using a Delrin STL file as the base. There are multiple options for developing a vibration-resistant
platform for the Pixhawk PX4 flight controller.
The Delrin plate will be mounted at the following
points of the Tarot frame (Figure 4.1-1).
The Delrin mount plate STL file has several portholes for managing wire leads to the Pixhawk PX4.
The adjacent mount points are for the
Pixhawk mount. There are multiple
options available for stabilizing a Flight
Control Board (FCB). The most
common and more effective form of
vibration dampening for the flight
controller is the separation of twin
plates connected by ball dampeners.
For this build, the platform was
supported by 12mm spacers and 8mm
Black Oxide screws.
For reference, after sufficient exposure to the elements Black Oxide screws may show signs of oxidation.
It is important to properly manage wires prior to mounting to avoid the complication while threading wire
through or below the Pixhawk PX4 flight controller in later steps.
Figure 4.1-1
Figure 3.3-5
Figure 4.1-2
Figure 3.3-5
Figure 4.1-3
Figure 3.3-5
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4.2 Pixhawk PX4 Flight Control Board Wiring and Control Elements
The Flight Control Board (FCB) Pixhawk should be centered and levelled on the mount (Figure 4.2-1).
Telem1 = Connection to 915MHz Receiver on the Forward Mount Plate
Telem2 = Connection to TX1 Single Pin Strip (custom connection)
Serial 4/5 = Connection to RTK GPS input UARTB
GPS = Connection to GPS
12C = Connection to Picoblade Connector strip
Power = Connection to internal Power Module
Main Out = Connections to Motors 1 – 6
RC IN = Connection to X8R FrSKY Receiver
AUX OUT:
o AUX1 connection to Landing Gear Module
o AUX2 connection to internal BEC
o AUX5 and AUX6 connection to respective LIDAR Lite V3 Connection
Figure 4.2-1
Figure 3.3-5
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The X8R FrSKY Receiver element communicates with the chosen Taranis programmable transmitter-
controller. Alternate transmitters options can be used provided they have the programmable capabilities
for multirotor flight operations.
For the BOGEY Hexacopter, the X8R will be
mounted on the upper face of the Rear Mount Plate
from build step (3.2) with double-sided tape.
Effort should be taken to ensure the security and cleanliness of wire connections as progress continues.
After the following intermediate steps, the result for this section should resemble (Figure 4.2-3) above.
Figure 4.2-2
Figure 3.3-5
Figure 4.2-3
Figure 3.3-5
Figure 4.2-3
Figure 3.3-5
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5 Top Plate; TX1 Onboard Computer Modifications
5.1 Delrin Top Plate Components
5.2 TX1 Onboard Computer Attachment and Wiring
Necessary Tools and Materials
12V BOSCH Impact Driver {Included Allen Key Bits:
3mm, 2.5mm, 2mm, 1.5mm}
Assorted Allen Keys {3mm, 2.5mm, 2mm,
1.5mm}
Pliers
Threadlocker
NVIDIA Jetson TX1 64-bit
A57 Computer
3D Robotics GPS
Module for Pixhawk
RTK GPS
RFD 900+ Modem
RP-SMA Extension Cable
(8inch)
(x2)
USB Hub
Pixhawk PX4 Safety Switch
Acetal Delrin Sheet
GPS Mast
Zip Ties
Velcro Tape
Carbon Fiber Rail
Nylon 6/6 Threaded Hex
Standoff 25mm
(x4)
Nylon 6/6 Threaded Hex Standoff 20mm
(x4)
Nylon 6/6 Threaded Hex
Standoff 12mm
(x4)
M3 Nylon Locknut
(x4)
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5.1 Delrin Top Plate Components
An Upper Delrin plate is needed to mount the TX1 onboard computer. The additional space for
modification will be used to mount the a USB Hub to link to the TX1, Dead switch, GPS Mast, and provide
a support mount for the RTK and Swift Navigation.
A component was 3D printed for support of the RFD 900+ mast component in future steps (Figure 5.1-1).
The USB Hub will be attached to the Delrin Top
Plate to receive data from the USB output from the
Fisheye camera mounted on the Delrin Front Plate,
data from the gimballed camera, and RTK GPS
input.
The leading output cable from the USB Hub will connect with the lead USB input to the TX1 onboard
computer in later stages.
Prepare the RFD 900+ with velcro tape to be secured to the
underside of the ring plate (Figure 5.1-4).
The SMA outputs will be connected to the 915MHz antenna that
were previously mounted to the Rear Mount Plate in stage (3.2).
Figure 5.1-1
Figure 3.3-5
Figure 5.1-2
Figure 3.3-5
Figure 5.1-3
Figure 3.3-5
Figure 5.1-4
Figure 3.3-5
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The RTK GPS is mounted to the Top Plat via a carbon fiber mast. This is done to prevent potential
interference from electrical components – specifically output interference from the TX1 computer.
Referenced in (Figure 4.2-1), the UARTB connection connects to the Serial
4/5 input on the Pixhawk PX4 Flight Control Board (Figure 5.1-6).
The UARTA connection will connect to the RFD 900+ module at the six-pin servo connector.
The microUSB output from the RTK GPS unit will lead to the USB Hub referenced previous
The Top Plate has has an
available port for the
attachment of the safety
switch (Figure 5.1-7).
This switch will connect to
the Pixhawk PX4 SWITCH
input.
The safety switch must be
manually actuated to
enable the arming
procedure prior to flight or
any future autonomous
operations.
Wires can be organized and secured with zip ties to avoid pull at the connection points (Figure 5.1-8).
Figure 5.1-5
Figure 3.3-5
Figure 5.1-6
Figure 3.3-5
Figure 5.1-7
Figure 3.3-5
Figure 5.1-8
Figure 3.3-5
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The Top Plate is supported by four pairs of stacked 25mm threaded spacers. This is a rapid and light-
weight solution to prevent conflict with the locations of the Pixhawk and TX1 computer (Figure 5.1-9).
The Top Plate will be secured to the threaded spacers to become level with the Pixhawk Flight Controller.
A second tier of threaded spacers will be attached to the upper face of the Delrin plate.
Wires can be organized and secured with zip ties to avoid pull at the connection points (Figure 5.1-11).
Figure 5.1-9
Figure 3.3-5
Figure 5.1-10
Figure 3.3-5
Figure 5.1-11
Figure 3.3-5
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5.2 TX1 Onboard Computer Attachment and Wiring
The TX1 Onboard Computer will be physically secured to the Top Plate via the upper threaded spacers.
Several modifications and connections must be made to properly integrate the NVIDIA TX1 onboard
computer. This will include a customized six-pin servo connector to the Pixhawk PX4 TELEM2 input. This
component will be necessary for the Pixhawk to communicate telemetry data with the onboard computer.
→ 𝑃𝑖𝑥ℎ𝑎𝑤𝑘 𝑇𝐸𝐿𝐸𝑀2
→ 𝑇𝑋1 𝐶76 𝑃𝑖𝑛 𝐼𝑛𝑝𝑢𝑡
Pin input location is shown in (Figure 5.2-3).
Figure 5.2-1
Figure 3.3-5
Figure 5.2-2
Figure 3.3-5
Figure 5.2-3
Figure 3.3-5
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The DC Plug created in an earlier section (Figure 3.3-2) will be woven through the existing structure to
provide a stable power supply to the TX1 onboard computer. The twin SMA input cables will link to the
pair of WIFI antenna that exit the SMA ports located on the Front Mount Plate (seen in Figure 3.1-2). The
USB hub will link to the single USB input to the onboard computer (Figure 5.2-4).
The final step of assembly is the attachment of the final Cap Plate, which entails twin thin Delrin sheets
with a metal film between to minimize electrical disturbance from the TX1 affecting the RTK GPS unit
(Figure 5.2-5).
Figure 5.2-4
Figure 3.3-5
Figure 5.2-5
Figure 3.3-5
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6 Project Overview and Operation
Necessary Tools and Materials
Xoar 18x6.5” 1865 Carbon Fiber Propellers
FrSky Taranis X9D Plus 2.4GHz with
RECEIVER
6S 10000mAh Lipo Battery
(x2)
Digital Capacity
Controller
Instructions for operating the Taranis transmitter are specific to this choice of operation. Standard
operation for the disarm procedure is to bring both joysticks to the bottom right location.
The BOGEY must be disarmed via the safety switch (seen in Figure 5.1-7) as part of the standard
Pixhawk PX4 flight procedures.
The BOGEY Hexacopter uses two 6S 10A LiPo batteries for sustained operation that have been
modified with AS150 connectors compatible to the input leads created in step (2.1). Each of these
batteries should be secured both with Velcro tape and straps. Lithium Polymer batteries can
create hazardous acrid smoke if they are damaged too severely due to a fall or rupture of the
cells. 6S 10A batteries can be considered dangerous if used or handled improperly, therefore
caution is advised. Steps should be taken to learn how to properly maintain and store your
batteries to avoid wear or deterioration due to mishandling or negligent maintenance.
The components of the BOGEY are capable of sustaining amperage of 40A when in high use
environments. Caution should be taken, and electrical training should be provided prior to
operation.
The conclusion of the steps and components provided in this manual assembles an unmanned
multirotor aircraft capable of flights times of approximately 20mins in high wind conditions varying
on the applied payload.
This manual was generated following the Mohammad Bin Zayed International Robotics Competition of
2017 (MBZIRC), during which Team VICTOR from the Terrestrial Robotics Lab at Virginia Tech would
receive 8th place in the first international challenge.
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References
Universal Laser Systems, Inc. (2005, August). M-360/V-460 laser Engraving and
Cutting System. http://www.engraversnetwork.com/files/Manual-M360-V460.pdf