BOGEY Hexacopter Build Manual - Virginia Techseb199.me.vt.edu/cms/wp-content/uploads/sites/42/...1.1 Tarot T810 Frame Instructions for the original frame body assembly are included

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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

[email protected]

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


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.



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.



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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


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 3.1-5

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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.


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



3mm, 2.5mm, 2mm, 1.5mm}


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)


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



3mm, 2.5mm, 2mm, 1.5mm}


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


Standoff 25mm

(x4)

Nylon 6/6 Threaded Hex Standoff 20mm

(x4)


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


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

BOGEY Hexacopter Build Manual - Virginia Techseb199.me.vt.edu/cms/wp-content/uploads/sites/42/...1.1 Tarot T810 Frame Instructions for the original frame body assembly are included

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