Heatseeker: 3D Printable Search and Rescue Drone

What this instructable will show you:

Search and Rescue drones are a life saving technology for disaster response, as they can provide real-time information, deliver supplies, and help locate survivors in inaccessible areas. Unfortunately, commercial SAR drones are often expensive and hard to repair.

This instructable will show you how to build a Search and Rescue drone that is cost effective, easily repairable, and customizable using 3D printing.

Uses of Search and rescue drones:

1. Provide a live video feed of a disaster site
2. Shows real time data so search and rescue teams know where to focus their efforts
3. Have either night vision or thermal imaging
4. Allow drones to locate survivors in dark environments
5. Ability to deliver emergency supplies
6. Provide immediate emergency supplies such as medication, first aid items, and food or water in areas inacessible by land vehicles.
7. Provide real time location data (GPS coordinates)
8. Transmit coordinates that allow rescue teams to know exactly where they are needed
9. Long flight time
10. Assist in long range rescue efforts deep into disaster zones

My goals for the design of this Search and Rescue Drone:

1. Guide Rescue teams
2. Locate survivors, deliver supplies to them, and lead them to safety with a siren-like beeper
3. Explore high risk areas
4. Conduct aerial scans

3D Printing Supplies:

1. PA6-CF Carbon Fiber Filament:
2. Used for durability and stiffness
3. PLA can be used, but your frame will be less durable
4. Used for the main frame of the drone
5. ABS Filament
6. Used for durability and impact resistance
7. PLA can be used, but your frame will be less stiff
8. Used in the drone's canopy
9. TPU Filament
10. Used for flexibility and shock absorbance
11. Used in mounts for electronics, spacers, and landing gear
12. Filament Drier
13. Used to dry filament after they have absorbed moisture
14. 3D Printer

Soldering Supplies:

1. Soldering Iron
2. Used to heat up solder and make electrical connections
3. Solder
4. Heated up to make electrical connections
5. Flux
6. Removes oxidation from solder joint and spreads solder evenly
7. Wire Strippers
8. Remove insulation from the wire

FPV Equipment:

1. ISDT 608AC Lipo/Li-ion Battery Charger
2. Used to charge batteries once they are depleted
3. Eachine EV800D FPV Goggles
4. Used to see out of the drone's camera while in flight
5. Radiomaster Pocket ELRS
6. Used to control the drone

Electronics:

1. Runcam Night Eagle 3v2 Infrared Camera
2. Used for providing camera footage in day and night but any camera with a width of 19mm would work
3. SpeedyBee F405 V4 Stack
4. Used as the brain of the drone
5. Includes the Flight Controller, Power Distribution board, and ESCs
6. HGLRC M100 5883 GPS
7. Used to transmit accurate GPS coordinates to be displayed and allows return-to-home
8. Optional
9. SpeedyBee TX800 Video Transmitter
10. Used to transmit video to the FPV goggles
11. Foxeer Lollipop 4 Video Transmitter Antenna
12. Used to increase video transmitter range
13. Optional if your video transmitter comes with an antenna
14. SpeedyBee Nano 2.4G ELRS Transmitter
15. Used to connect your drone to your controller
16. ViFly Finder 2 Buzzer
17. Used to make a sound, useful after crashes
18. Optional
19. YSIDO 2806.5 SpeedBat V8 1300KV Motor
20. Used to spin propellers and make the drone fly
21. Auline 21700 4000mAh 6S 22.2V Battery
22. Used to provide power to the drone
23. XT60 Male Connector
24. Used to connect the ESC (electronic speed controller) to the battery
25. 22 AWG Stranded Wire
26. Used to connect the resistor to the ESC

Additional Hardware:

1. HQProp 7X3.5X3V1S 7 inch propellers
2. Used to generate lift
3. Apex RC Products 5 Pack 20mm x 300mm HD Rubberized Battery Straps
4. Used to hold the battery in place on top of the drone
5. Heat set inserts
6. Used to allow screws to be used in the 3D prints
7. Screws
8. Used to assemble the drone frame and hold electronics in place
9. Double sided tape
10. Used to secure small components

Optional:

1. SpeedyBee FPV Soldering Practice Board
2. Used to practice soldering before soldering the final components

Note:

You can swap out any component you want, but you may need to adjust the 3D model with CAD to fit the new dimensions or mounting points.

Files:

All part files can be found on this thingiverse page. All files are in the STEP, allowing you to modify them after downloading.

Notes:

Files that begin with a number (ex: 4xArm-PA6-CF.step) indecate how many times that part should be printed

1. Each file ends in the recomended print material

When printing this I used PA6-CF for the main body and ABS for the canopy of the drone for their elevated durability and heat resistance.

1. These can both be printed in PLA but the results will be less durable.

PA6-CF and ABS produce harmful particles, so it is recomended to print in a well-ventilated area.

1. A heating chamber benefits these materials as it reduces warping
2. PA6-CF must be kept dry with a filament dryer for optimal print quality.

No supports were needed for the TPU parts.

Introduction to heat-set inserts:

Heat-set inserts are small brass threaded tubes with knurls on the outside which you melt into prints with a heated soldering iron. This allows reusable threads and strong connections.

Instructions:

Take any part and use the given diagram to determine which insert goes into which hole. Heat up your soldering iron and place the heat insert on top of the hole. Once the soldering iron is heated, place the tip into the threaded hole and push down so that the insert melts into the plastic. If it does not push in, increase the temperature.

Notes:

The heat-set insert types in my diagrams are classified by insert thread size x insert depth x insert outer diameter

1. ex: M3x3x5 = M3 thread x 3mm length x 5mm outer diameter

Different heat settings for your soldering iron will be used for different 3D printer filaments. From my experience the following settings worked but you may have to experiment:

1. PA6-CF: 600° F
2. ABS: 500° F

It is better to have a lower temperature than a higher temperature, as a high temperature can cause the insert to go in too far and weaken the surrounding plastic.

I recomend practicing on a test print to figure out the proper temperature and timing.

Sometimes some plastic will bulge at the top as you push the insert in.

1. You can trim it with flush cutters/filament cutters once the part cools.
2. Make sure the insert is flush with the surface of the part.

Instructions:

1. Prepare the ELRS antenna mount and ensure the filleted holes are on the bottom. Take the ELRS antenna (T-shaped) and spread the mount enough to push the antenna through the holes on both sides. Let the mount snap back together and pinch the two sides together to grip onto the antenna securely.
2. Attach the antenna mount onto the two rear supports with the filleted holes facing the bottom.
3. Insert the antenna into the Lollipop mount's center cylinder. After this, ziptie the cylinder to improve hold on the antenna and clip the VTx onto the connector cable.
4. Place the Lollipop mount onto the two rear supports, on top of the ELRS mount, with the antenna tilting towards the rear. Connect the Lollipop to the VTx.
5. Position the VTx close to it's 4 mounting holes.
6. Take the ELRS mount and push 4 m3x20mm screws through the top holes. Slide the ELRS spacers onto the screws after this.
7. Use the remaining length of the screw to screw in the VTx.
8. Connect the VTx's wire and twist it. This will help during soldering.
9. Put a washer on an m3x40mm screw. Repeat this 4 times.
10. Thread this screw through the four center holes without inserts. Once the washer is touching the base, place the TPU ESC spacers onto the exposed part of the screws.
11. Slide all 4 arms into the holes in the body. If they are tight, you may have to put them in the freezer for 20-30 minutes to make them an easier fit.
12. Use M3x8mm screws to secure the arms to the body using the 2 screw holes on top and the two screw holes on the bottom. Ensure the connections are tight.
13. Continue to the next step, Soldering, before we continue building.

Notes:

Do not overtighten the screws into the plastic inserts, make them just tight enough for a strong connection.

Do not mix up the TPU spacers. Please use these descriptions and the image to identify them.

1. ELRS spacers are the shortest
2. Flight Controller spacers have a cutout on the bottom part
3. ESC spacers are tall with no cutout

Recommendation:

Before trying this on real electronics, I recomend you order an FPV practice board to get comfortable with using a soldering iron.

If this is your first time soldering, you should watch this video. Some vocabulary you will need to know is:

1. Tinning: Tinning is applying solder onto a pad or wire to make it easier to bond them together later
2. Flux: Flux is a chemical cleaning agent used to remove oxidation from a solder joint. It also helps keep heat distribution even and leads to cleaner solder joints.

Instructions:

1. Tin the top and bottom of the large ESC pads.
2. Solder the battery lead (XT60 connector) and 22AWG wire connecting to the large pads on the ESC.
3. I have provided a wiring diagram as well as a picture of my own solder above. Ensure that your capacitor wires are going the opposite direction from the XT60 connector. The XT60 connector must be soldered at an angle similar to that shown on my picture so it does not collide with the ELRS mount.
4. Tin the motor pads.
5. Attach the flight controller ribbon wire to the ESC.
6. Push the ESC down onto the 4 tall screws and make the XT60 connector face the rear of the craft. Use double sided tape to fasten the capacitor into the front ridge.
7. Insert the motors into the arms and secure them with m3x12mm screws and route the wires through the hollow part of the arm.
8. Cut the motor wires to length and strip off some of the insulation. Tin the wires.
9. Connect the motor wires to the ESC motor pads as shown on the wiring diagram. The order of the wires does not matter. Repeat this with all 4 motors.
10. Place the flight controller spacers onto the long screws with the indented side facing the wires.
11. Screw the camera in between the two camera mount parts using the m2 screws that came with the camera. You will be able to slide this into the bracket on the front of the base.
12. Place the flight controller on top of the spacers (above the ESC) and connect the ESC's ribbon cable. Use the wiring diagram to solder the components to it. The wiring diagram may change for some components, as my buzzer needed a connection to the GND pad, so if you have any components that have a different amount of wires than that on the wiring diagram, find the manufacturer's instructions for it's soldering.
13. Once you have soldered the ELRS chip, use double sided tape to secure it onto the ELRS mount. Connect the antenna to the chip.
14. Secure all other loose components such as the buzzer and OSD control module with double sided tape as well.
15. If you have a GPS, keep the wire loose and do not plug it into the GPS yet.
16. Use the nuts that came with the flight controller to secure it in place by bolting it down.

Notes:

Only solder the components you have. You will likely not have to tin all the pads.

If you are using a different flight controller, use the manufacturer's wiring diagrams.

If you have a GPS:

1. If you have a GPS, push the wire through the small, rectangular hole near the back of the canopy and pull it through before pushing the canopy onto the pegs.
2. Once you are done attaching the canopy (see instructions segment), on the rear facing battery strap, put your GPS mount with the cable hole facing back. To mount the GPS you will have to insert the ridge on the GPS under the ridge on the mount. Then you will push down on the GPS until you can see the connector on the rear-facing hole.
3. Take the cable and plug it into the GPS.

Instructions:

1. Push the canopy onto the pegs and line the holes up with those on the base. It will take a push to get it to snap into place.
2. Push the battery connector into the battery connector mount. Put the mount into the large rectangular hole in the rear of the canopy and make sure your orientation aligns the screw holes.
3. Screw down the top two holes near the front of the canopy with any length of m2.5 screws. Screw down the rest of the holes on the canopy and battery connector mount with any length of m3 screw. Screw the side holes on either side of the canopy with any length of m3 screw. Tighten them until you have a firm connection.
4. Slide battery straps through the canopy slits.
5. To mount the landing gear you will ensure that the slanted side is pointing away from the drone body. Then you will spread the bottom two parts of the leg and push down until it comes back together. Then you will place the sock over the leg and make sure that the slant is pointing away from the drone body here as well.
6. Slide the landing gear along the arm until you can see the screw hole from the top hole.
7. Use an m2.5x5mm screw to fasten it
8. Push any m3 screw over 24mm through the two holes in the sock and the leg and then hold them in place with nuts.
9. Repeat this for all 4 landing gears.

Notes:

Do not attach your propellers until you have set up the drone's software.

Instructions:

1. For this stage of the setup, I followed this video. Skip to 2:10:30 to get to the configuration portion of the build.

Notes:

1. After software setup you may screw your propellers tightly onto the motors. Place the washer that came with your motors, ridge side up on the shaft. Put the propellers on top, and then tighten the nylock nut securely.
2. Make sure the higher part of your propeller is in the direction that your propeller rotates.

Instructions:

1. Plug and unplug your battery onto the drone 2 times and then plug it in as fast as you can. This will put your flight controller and receivers/transmitters into binding mode.
2. Use the the channel and power in the Betaflight VTx tab
3. For the Eachine EV800Ds, use the channel/band button on your goggles to get onto the right channel and band. Hold down the button to transition between the two modes.
4. For the Radiomaster pocket, click the SYS button to enter the tools menu and click the scroll wheel when ExpressLRS is highlighted in black. After this you will want to scroll down until you find the Bind option, in which case you will click the scroll wheel again to put it in bind mode.

Notes:

1. Refer to the user manual or online resources to find the connection instructions for your specific FPV goggles and controller.

Instructions:

1. Charge your batteries and equipment pre-flight.
2. Check all screws and mounts to make sure nothing is loose, especially the propellers.
3. Go to a safe location to fly, ideally a wide and open area.
4. Arm your drone, try hovering and test out basic controls.

Notes:

1. I fly this drone in angle mode, but you are free to fly it in any mode that you want.