My grandson enjoys driving a remote controlled (RC) truck, and we wanted to add First Person View (FPV) video to it.
After researching many possible video methods, I decided to use a tiny camera that would not look too large for the truck, and have it communicate in such a way that the video feed could be viewed on a TV, or goggles, or a portable DVD player.
Step 1: PARTS
If you don’t have an RC truck, buy one that has a deck behind the cab, large enough to hold a 4-cell AA battery holder. Cheap trucks may be bought for around $30 to $40.
PARTS FOR FPV
At the time of writing this instructable, the camera, transmitter and receiver I chose were each priced at $19.99 in US funds at http://www.robotshop.com/ or $26.65 in Canadian funds at the Canadian location http://www.robotshop.com/ca/en/ There are cheaper units available on Amazon, but they are shipped from China, and I thought that units from a reputable North American company would be sure to be reliable even though they are also made in China.
- Camera: “700TVL Camera Module for 250 Quadcopter” runs on 12v. http://www.robotshop.com/en/700tvl-fpv-camera-mod...
- Transmitter: “8 Channel 200mW 5.8GHz Wireless Audio/Video Transmitter for FPV” has a built-in microphone and transmits the audio with the video. Runs on 12v. http://www.robotshop.com/en/8-channel-200mw-58ghz...
- Receiver: “Helistar 5.8G FPV Wireless Receiver” runs on 6.5 to 15v. http://www.robotshop.com/en/helistar-58g-fpv-wireless-receiver.html
- 2 - 4-cell AA battery holders with a built-in switch. Two holders fit better in the truck than one 8-cell holder. The truck uses six AA batteries and I thought of making use of them and adding two more, in series, for the camera and transmitter, but I thought it would be easier and better to have a separate set of batteries.
- 1 - 6-cell AA battery holder with a switch, either built-in or separate. I couldn’t find one with a built-in switch. This is for the receiver.
- 1 - male-male, 3-wire RCA cable, to connect a TV to the cable supplied with the receiver. If audio isn’t important to you, a single-wire RCA cable will do the video. A different cable may be needed for goggles or a portable DVD player, having RCA connections at one end for the receiver cable, and a 1/8 inch (3 mm) audio/video plug at the other (or a cable with audio/video plugs at both ends to go from the receiver directly).
PARTS FOR BRACKET FOR CAMERA
- 1 - Plastic lozenge box to make the camera holder
- 1 - Dental floss box to make the bracket to hold the camera holder on the truck
- 4 - half-inch long #2 roundhead bolts, lock-washers and nuts for the camera
- 2 - quarter-inch long #4 roundhead bolts, lock-washers and nuts for the bracket
- 2 - three-eighth-inch long #6 roundhead screws to attach the bracket to the truck
- 1 - Sprayer from a bottle of a cleaning product, whose tube has the proper inside diameter for a #2 bolt to slide inside. Some sprayers have tubes that are too small or too large.
- Electrical tape
- Soldering iron and solder
- Needle-nose pliers
- Screwdrivers to fit the bolts and screws
- Drill and drill bits
- Utility knife
- Tinsnips or scissors
Step 2: Make the Holder and Bracket for the Camera
- Cut the lozenge box so that the camera fits inside. File the edges smooth. This is the camera holder.
- Cut the dental floss box to hold the holder. File the edges smooth. This is the bracket.
- Measure and drill holes in the camera holder to match the mounting holes in the camera circuit board.
- Cut four pieces of the sprayer tube, each piece 1/4 inch long. These will be the stand-offs to hold the camera circuit board away from the holder.
- Attach the camera to the holder with the #2 bolts, sprayer tube pieces, lock-washers and nuts.
Step 3: Attach the Bracket to the Truck
- Cover the bracket with electrical tape to make it black instead of white.
- Drill two holes in the bottom of the bracket so that the #6 screws slide in easily.
- Place this on the top of the truck cab, and mark where the holes sit.
- Drill pilot holes there for the screws.
- Attach the bracket to the truck.
- Use the #4 bolts, lock-washers and nuts to attach the camera holder to the bracket.
Step 4: Attach the Battery Holders to the Truck
- Place eight batteries in the two 4-cell battery holders after making sure the switches on the battery holders are off.
- The deck behind the cab of our truck was a little too short for the battery holders. I had to cut off the bumper at the back, using the hacksaw and tinsnips, to fit one battery holder underneath the deck. The wires should lie towards the back of the truck.
- The wires from the camera can be on top of the deck, running towards the back of the truck, with the second battery holder sitting on top of them.
- An elastic holds the two battery holders in place.
Step 5: Place the Transmitter
The transmitter sits on top of the upper battery holder, held by another elastic. The black and red power wires from the battery holders and the transmitter lie to one side. The wires from the camera and the five-wire bundle from the transmitter should lie under the upper battery holder, running towards the back of the truck. The elastics make it easy to lift the upper battery holder and slide the wires under it.
Some of the wires have connectors, but I cut them off and soldered the proper wires together. Electrical tape goes around each connection.
- The black wire from one 4-cell battery holder goes to the red wire of the other battery holder, in order to connect the batteries in series to produce 12 volts. The remaining black wire from the battery holders goes to the black wire of the transmitter power wires. The remaining red wire from the battery holders goes to the red wire of the transmitter power wires.
- The wires from the camera and the five-wire bundle from the transmitter should be sticking out the back of the truck. The camera has three wires: yellow, red and black. The transmitter has five wires in its output group: yellow, red, black, white and green. The white and green wires are audio output and don’t connect to anything. The other like-colored wires go together: yellow to yellow, red to red, and black to black.
- After soldering the wires and wrapping electrical tape around the solder joints, you could tuck the wires in the elastic under the lower battery holder.
The switch on the battery holder that is under the deck should be turned on, and kept on. The power will be controlled by the switch on the upper battery holder.
Step 6: Connect the Receiver
- Place six AA batteries in the 6-cell battery holder.
- Put the receiver on top of the battery holder and secure it with an elastic.
- If the battery holder has a switch, solder the corresponding wires of the battery holder and receiver, red to red and black to black. If there is no switch, one can be wired in, between the two red wires.
- Wrap electrical tape around the solder joints.
- Tuck the wires under the elastic.
Step 7: Enjoy Using It
- Use a male-male, 3-wire RCA cable to connect the receiver output cable to a TV. If audio isn’t important to you, a single RCA cable will do the video. A different cable may be needed for goggles or a portable DVD player, as described in the “Parts for FPV” section above.
- Turn on the receiver power and the truck power.
- The video feed should be visible on the TV.
When the receiver is outdoors with a long cable to the TV inside, and a clear line of sight from the transmitter, the range is excellent. I took the truck down the street while speaking on a cell phone with my wife as she watched the TV, and the video and audio were still very clear at 150 meters or 165 yards. I didn’t go any farther.
But when the receiver is inside the house and the truck is driving outside, the brick and concrete block walls of our house and garage degrade the signal, and the range is only about 50 meters or 55 yards.
Step 8: Future Improvements
Now that the basic video feed works well, I’m thinking of some improvements.
As mentioned near the end of Step 7, one way to increase the range is to mount the receiver outside and run a long cable to the TV inside. It should be on a pole to be above any obstructions and traffic. Another way to increase the range is to get a more powerful transmitter.
The camera is surprisingly sensitive at very low light levels, but, of course, doesn’t produce an image in utter darkness. I plan to try shining several infrared (IR) LEDs in front of the truck to see if that allows the camera to see. If it does work, the LEDs could be mounted as headlights on the truck.
When I get my planned autonomous robot working, I will move the camera system onto it to view where it decides to go.