The Simple Phone Gimbal
This Instructable walks you through an inexpensive and easy-to-follow process to create a functioning gimbal for your own smartphone. A gimbal is a device that stabilizes a camera to counteract human movements resulting in higher-quality videos. These are usually high-tech products that can cost quite a bit- but you can make this one in just a few hours for under $100!
Learn more:
What's a gimbal? [1]
Supplies
Electrical
- Adafruit 3-Axis gyroscope L3GD20H
- Heat sink for voltage regulator
- Battery holder for 4 AA batteries
- 2x 4.7kΩ resistors
- Jumper wires of various sizes
Mechanical
- 4x- ¼-20 bolts, 1.5” long
- 8x- ¼-20 hex nuts
- 12” of 3” diameter PVC pipe
- 6” of 2” diameter PVC pipe
- 18” of 1.25” diameter PVC pipe
- 1x 1.25” diameter PVC tee connector
- 1x 1.25” diameter PVC elbow connector
- 2x 3” diameter PVC cap
- Hot glue sticks
- Cardboard
- Optional: soft material such as felt
- Optional: 2x zip ties
Tools
- Hot glue gun
- Hand drill
- Hand saw
- ¼” drill bit
- ½” drill bit (a step drill works best)
- 1.25” hole saw
- Scissors
Cutting
Use a hand saw (or band saw if you have one) to cut the following PVC pipes:
- 1x-12” long, 1.25” diameter
- 2x- 6” long, 1.25” diameter
- 1x- 2” long, 2” diameter
- 1x- 2” long, 3” diameter
- 1x- 6” long, 3” diameter.
Also, carefully cut a slot through the center of the T-connector slightly wider than your phone.
Drilling
Use a hand drill (or drill press) to create the following holes in the PVC pipe:
- 1.25” hole through the center of one end cap
- 2x .25” holes off-centered on the center cap (the specific location doesn’t matter)
- .25” hole, 3” from the top of the 12” long, 1.25” diameter pipe going all the way through
- A .25” hole, centered going all the way through and a .5” hole centered, going all the way through 90deg from the .25” hole on the 2” diameter pipe
- A .5” hole, centered, going all the way on the2” long, 3” diameter pipe and a 1.5” hole 90deg from those two holes centered on the pipe.
Glue
- Use a hot glue gun to carefully glue the bearings into all four .5” holes. Be sure not to get glue into the bearings as this will prevent them from spinning freely.
- Glue the 12” long, 1.25” diameter pipe into the 1.25” hole in the end cap. The end of the pipe should be even with the inner ceiling of the cap.
- Glue one of the 6” long, 1.25” diameter pipes to the 1.25” hole in the 2” long, 3” diameter pipe. The end of the pipe should not extend into the inside of the pipe more than ¼”.
Assemble
- To assemble, push two screws (one through each bearing) from the outside inwards through the largest ring. These will end in the small holes of the middle ring. Use nuts to secure the screws in place. Then, push two more screws through the bearings in the central ring through the two small holes in the 12” long, 1.25” diameter pipe. Once again, use nuts to secure in place. This should allow the two axes to rotate around the screws.
- Insert the 6” long, 3” diameter pipe into the cap connected to the long 1.25” pipe and insert the other end cap (with the two small holes) onto the other end.
- Attach the elbow connector to the 1.25” pipe attached to the outer ring and attach the other 6” long, 1.25” diameter pipe to the other end of the elbow to create a handle.
Final Touches
- Glue padding (such as a sponge, felt, or fabric) to the insides of the slit in the T-connector
- Attach the T-connector to the very top of the central pipe
- Optionally add zip-ties, rope, or something similar so that you can tighten the phone holder.
Place Components Into Breadboard
- Place the Teensy on the left side of the breadboard with pins 0-11 on the bottom side of the trough and pins 14-22 on the top side
- Place the L3GD20H gyro on the right side of the board being sure the square black chip is as close to center as possible
- Place the L7805-sch 5V regulator on the top left of the breadboard. I attached a small heat-sink to the back of mine. This is optional and not necessary.
Wire Onboard Components
- Connect a jumper from pin 2 of the L7805-sch 5V regulator to the top ground rail on the breadboard and a jumper from pin 3 of the L7805-sch 5V regulator to the top +V rail
- Connect a jumper from the 5V pin on the Teensy to the +V rail and a jumper from ground on the teensy to the ground rail
- Using the 4.7kOhm resistors, connect pins 18 and 19 to the +V rail
- Using a jumper, connect the SCL pin on the L3GD20H to pin 19 on the Teensy and the SDA pin to pin 18 on the Teensy
- Connect a jumper from the Vin pin on the L3GD20H to the +V rail and a jumper from ground to the ground rail
Create Off-board Component Wires
- Cut a 6in long length of speaker wire and push a header pin into each of the wires on one side and wrap with tape. Push the leads of the toggle button into the ends of the wire.
- Cut another 6in long wire and again push header pins into each of one side of the wires and wrap with tape. Push the leads of the push button into the other side.
- Cut two more 6in lengths of speaker wire and pull the wires apart on one of them as we only need three individual wires. Push header pins into both sides of all the wires. Tape the wires together on one side
Connect Off-board Components
- Connect one lead of the toggle button to pin 1 of the L7805-sch 5V regulator. The other will be connected with the battery so for now we can just connect it to somewhere on the bottom left of the breadboard.
- Connect one lead of the push button to the ground rail and the other to pin 14 of the Teensy
- Take the three-wire connector we made and connect one wire to the V+ rail, one to the ground rail and the last to pin 10 on the Teensy. Be sure to take note of which wire is where, as this will be important when connecting the servo motor
- Connect the wire in the V+ rail to the red wire on the servo. Connect the wire in the ground rail to the brown wire on the servo. Connect the last wire to the orange wire on the servo.
- Finally, connect the red wire of the battery connector to the lead of the toggle button that we set aside earlier and the black wire to the ground rail. It is very important that the red wire never gets connected to the V+ rail directly or you will fry all your components.
Code
To upload the code, download the attached file and open it in the Arduino IDE. You then need to download Teensy Loader. This can be done by visiting https://www.pjrc.com/teensy/loader.html [4]. After installing this, you can upload the code just like you were using an Arduino. If it has any problems, push the Teensy’s onboard button when Arduino is in the uploading phase. Remember to never connect the Teensy to your computer while it is running from the 9V.
Downloads
Mechanical-Electrical Integration
- Cut one rectangle of cardboard that is narrow enough that, when placed in the pipe, will ensure that the gyro is centered in the pipe (this should be slightly below the center to account for the height of the breadboard.
- Cut two 1.25” circles, one circle should also have a rectangle the size of the servo cut out.
- Glue the servo to the cardboard with the rectangle cut out and then (after pushing the wire of the servo through the pipe) glue the circle to the top of the central post. Trim edges of cardboard so that it is flush with the outside of the pipe.
- Glue the servo blade to the other circle of cardboard, centered.
- Attach the servo blade back to the servo, place the T-connector back on the pipe, use a marker to mark where the cardboard stops. Then remove the T and glue the cardboard in the place marked. Reassemble the top of the gimbal.
- Glue the cardboard rectangle into the base of the gimbal, attach the breadboard by peeling off the film and sticking it to the cardboard, again making sure the gyro is centered in the pipe.
- Wire the two buttons through the two small holes in the end cap and glue them in place.
References
[1] “(10) WHAT IS A GIMBAL – HISTORY AND APPLICATION? (In the Entertainment industry. What is a Gimbal – History and Application) | LinkedIn.” https://www.linkedin.com/pulse/what-gimbal-history-application-entertainment-industry-bruce-bisbey/ (accessed Oct. 07, 2021).
[2] “How Does a 3 Axis GoPro or DSLR Gimbal Work?,” EVOGimbals.com. https://www.evogimbals.com/blogs/evo-blog/how-does-a-3-axis-gopro-or-dslr-gimbal-work (accessed Sep. 04, 2021).
[3] “Teensy Loader Application - available for Windows, Linux and Macintosh systems.” https://www.pjrc.com/teensy/loader.html (accessed Dec. 12, 2021).