Difference between revisions of "FPV"
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==== Diversity Controller ==== | ==== Diversity Controller ==== | ||
* Oracle Video Diversity Controller - Monitors video signal from two receivers (with different antennas), picks the better, opposite of RSSI-based selection [http://hobbywireless.com/cart/index.php?main_page=product_info&products_id=70] [http://www.team-blacksheep.com/article/page:19] | * Oracle Video Diversity Controller - Monitors video signal from two receivers (with different antennas), picks the better, opposite of RSSI-based selection [http://hobbywireless.com/cart/index.php?main_page=product_info&products_id=70] [http://www.team-blacksheep.com/article/page:19] | ||
* Immersion RC Duo5800 diversity receiver - Two Airwave receiver modules built-in | |||
* Immersion RC Duo2400 diversity receiver - Exactly the same as 5.8GHz but different Airwave modules | |||
==== Antennas ==== | ==== Antennas ==== |
Revision as of 20:03, 24 May 2011
Flying electronic RC planes from the ground is fun. Piloting a FPV plane from First Person View is really cool. With the arrival of light and powerful video stream transmitters and long range remote RC transmitter modules , the range of flight has increased from line-of-sight to an order-of-magnitude wider.
Research
To build a reliable platform I want to begin with the fundamental basics and then extrapolate more specific products.
Electronics
- Lower frequency will allow greater range, longer wavelength requires larger antenna
- Higher frequencies, 2.4GHz or 5.8GHz, will quickly get attenuated by the atmosphere
- One energy-source, single set of batteries for motor, camera, OSD, VTx, Rx, servos
- Minimized weight, as batteries contribute as the heaviest component
- Receiver antenna diversity for maximum flexibility of the airplane, each antenna 90 degrees perpendicular
- Omni-directional antennas will have a radiation pattern much like a form of a doughnut, with dead-spots center, above and below
- Same radiation polarization on ground station and airplane where possible, alternatively circular polarized ground antenna
- Signal quality of same polarized electric fields can be many tens of dB different [1]
- Parallel 3S 11.1V Lithium-ion Polymer batteries, both on plane and ground station
- Prevents voltage drop if one cell is bad, might add reverse current protection (diode) to avoid 3S "charging" the then 2S battery
- Power- and signal-wiring separated as much as possible
- Noise from motor can degrade digital signals if coupled with signal-wires
- Shielded components, twisted wires, ferrite rings, and condensators will eliminate most noise and oscillation, PCB ground plate facing interference source
- Minimize both ambient noise and interference from nearby components, think of a long wire as an antenna that will pick up anything
- Video-transmitter on a higher frequency band than RC-transmitter, 1.3GHz VTx and 433MHz RCTx, 2.4GHz VTx and 433MHz RCTx
- Having the same frequency/band on VTx and RCRx will cause signal degradation
- Video-transmitter, as well as RC-receiver, powered by 5V voltage from main Lipo-batteries via BEC
- When the main engine batteries are drained or the ESC unexpectedly shut down, a separate BEC will continue to power the rest of the 5V system, 12V directly connected will require more filtering
- Split aileron servo signal to use twin ailron servos for each wing
- Prevent loss of control on servo failure, must be mounted close together to drive force-drive the dead servo, might drop this
- Proper cooling of video-transmitter using an appropriate heat-sink and thermal-adhesive
- Powerful video transmitter dissipate a lot of power in form of heat, prevent signal loss
Plane
- A wing for speed and stability
- Makes it possible to fly in windy condition and greater distances, less drag
- Batteries in front and electronics behind the batteries, suitable motor to create enough lift
- Front heavy for stable dives when motor is inactive and in up- or down-drift
- Find the center of gravity by temporarily putting everything where they're supposed to go
- Makes it easier to find where the sparing bars between the wings will go and position of the motor mount, leave the battery location to last for fine tuning CG
- Motor mount on or close to the center of gravity
- Easier to handle during acceleration and less wobbly when the force is pushing the center instead of the back end, imagine a horizontal axis over the wings as center of gravity
- Keep the servos, transmitters, and battery packs as near the center as possible
- Makes the flight more stable in windy conditions, instead of wobbling back and forth because of inertia
- Antenna for VTx mounted at the end and center of the left-wing, while the two RC-receiver antennas on the other right-wing, shifted 90 degree
- Minimize interference between the two radio systems, 90 degree angled to allow cross-polarization, both vertical and horizontal for better signal quality at different plane orientations
- Servo location as far forward as possible to put center of gravity back
- Push-rods on an angle does not affect the elevator action, might put but more pressure on the servo [2]
- Mount the motor outside the mounting plate, against the back
- More continuous airflow results in quieter throttle up and high speed flight [3]
Gear
Use this as a guide to ballpark what is needed and then just pick whatever falls inside your needs and specifications.
Video system
Cameras
Preferred voltage is 5V to avoid boost/step-up converters and switching noise isolation.
Recording:
- GoPro HD Hero - High-definition on-board recording
- Contour HD - Another HD on-board recorder
- Aiptek HD - Small hd cameras [4]
- KeyCam HD #11
Flying [5]:
- Globe Flight GF-PX540 - Pixim PX540 CMOS sensor, resolution 540 lines, pricey, 1/3-inch sensor, lower 1/3 brighter, high quality 3.6mm lens, 22 grams, 10-12V [6] [7] [8] [9]
- DX201 DPS camera - 540 lines, excellent image quality, based on same Pixim CMOS sensor as above, 12V [10] [11] [12] [13] [14]
- DPC-480A / RMRC-480 / NGH-480A / BEV OSC 480 - 480 lines, great colors, 1/3-inch sensor, can configure brigher zones, 36 grams, 12V [15] [16] [17]
- Fatshark RCV922 camera - Resolution 420 lines, 1/3-inch sensor, lower 1/3 brighter, unsaturated colors, 3.6mm and 2.8mm lens, 30 grams, 3.3-5V [18]
- WDR600 - 550 lines, 1/3-inch sensor, 12V [19]
- Fatshark CCD killer - 420 lines, light, comes with pan/tilt setup, cmos sensor (apparently kills ccd), 3.3V-5V
- Black Widow KX131 - 380 lines, 1/4-inch sensor, nice colors, value, 23 grams, 5V [22]
- FPVCAM-480 OSD - Resolution 480 lines, 12V [23]
- SONY KPC-VSN505PHB - 550 line resolution, rf noisy but can be fixed [24], 5V
- Sony SN555/VSN700 camera - 555 line resolution, excellent low light performance, 29 grams, 12V [25]
- DPC-161 - Cheap, resolution 380 lines, 5V [26]
- Sony SN777 - Same as VSN505 [27], 555 lines resolution, 12V, RF noisy [28] [29]
- KX-171 - 5V, too dark in sunlight, LVP and G2 might be better [30] [31]
Transmitters
Preferably use 2.4GHz band as it's safer, won't interfere with other, no high powered devices on band, 900MHz overpowered by mobile phones, 1.2GHz aviation communication [32]
- Lawmate 500mW 2.4GHz Tx - 5-5.5V, 12 grams, use ch5 2370MHz and ch8 2510MHz, outside regular band, noise-free, mod for better cooling [33] [34] [35] [36]
- IntelligentFlight GP-707 2.4GHz 10mW micro audio/video transmitter - 1.6 grams, comes with receiver [37] [38] [39]
- Sunsky 1.2GHz 400mW [40] [41]
- Sunsky 1.2GHz 800mW [42]
- BEV 1.3Ghz 800mW transmitter, 12V [43]
- ImmersionRC / Airwave 600mW 5.8GHz A/V transmitter - Built-in 5V regulator for camera, 6-16V
Receivers
- Lawmate 2.4GHz RX-2460CK receiver - 8 Channels, 12V DC in, minimum 10V DC, small, Comtech FM2400RTIM8 module [44] [45] [46] [47]
- IF 2.4GHz GP-737 / GP-707 receiver - only 4 channels, hair better than Lawmate 2.4GHz [48]
- RangeVideo 1.3GHz Deluxe receiver - RSSI 0-5V output
- EagleEyes FPV Station - Receiver with antenna diversity, antenna tracking
Diversity Controller
- Oracle Video Diversity Controller - Monitors video signal from two receivers (with different antennas), picks the better, opposite of RSSI-based selection [49] [50]
- Immersion RC Duo5800 diversity receiver - Two Airwave receiver modules built-in
- Immersion RC Duo2400 diversity receiver - Exactly the same as 5.8GHz but different Airwave modules
Antennas
A 14 dBi patch antenna has a narrower radiation beam than a 8 dBi patch antenna. A focused 14 dBi yagi for a focus beam in one direction.
- Clover Leaf - Circular polarity, use identical pairs for receiver and transmitter
- Active Robots 433 MHz 1/4 wavelength straight and angled - On the plane
- Antenna for 2.4Ghz 9dBi Omnidirectional [51]
- Maker your own Sander-style omni-directional SMA antenna - Lighter than any purchased item, can be tuned to exact wavelength of frequency
OSD - On-Screen Display
- ImmersionRC EzOSD - Uncluttered display, GPS on-board, signal strength indicator via I2C, current/voltage sensor with Deans
- SimpleOSD - Minimalistic, only the most necessary information [52] [53]
- Eagle Tree OSD Pro
- DOSD
Goggles
Resolution is limited by the camera not the goggle, best camera can deliver 480 lines [54], though sensor might state a higher resolution but it's not delivered.
- Carl Zeiss cinemizer plus - Adjustable fit, 32 degrees viewing angle, better optics, 640x480, screen smaller but higher resolution/optics, small box, half immersed, better color and contrast than Fatshark, diopters adjustment -3.5 to +3.5D, longer video switching than Fatshark [55] [56] [57]
- Fatshark RCV922 V2 Base Edition - Wide angle 46 degrees, 80-inch on 2 meters, 640x480, fully immersed, adjust for interpupil distance, video and power inputs, FPV ground station friendly, 6-12V [58]
- HeadPlay Googles - Adjustable, 800x600 resolution, requires exactly 12V, large box [59]
- EVG920 Video Eyewear - Not adjustable interpupil distance, 80-inch on 2 meters, 640x480, 1000 mAh battery, 5V [60]
- Fatshark RCV230T/922T Teleporter - All-in-one, limited 320x240 resolution and range [61]
- Fatshard RCV922 Aviator - Video input, 640x480 resolution, Vin 6-12V [62]
Display
- Haier HLT10 10.2-inch LCD display - for ground station, audience view, 12V
Recorders
- Lawmate PV500 EVO - 720p video recorder, pricey [63]
- Archos 604 - Groundstation video recorder [64]
- Pinnacle Video Transfer - Video recorder [65]
Misc
- Immersion RC PowerBox - Groundstation video and power filtering box
Control system
Radios
On UHF will the 35/72MHz transmitter not be used, the PPM signal is feed to the long range transmitter.
- Futaba 6EXP PPM/PCM 1024 35MHz [66]
- Futaba 9CHP-PCM 36MHz [67]
- Futaba T9CAP PCM/FM [68]
- Futaba 10C 10-Channel Computer Radio [69]
- Futaba 10C/9CS/9C 72MHz Synthesized Module [70]
- Spektrum DX7 - Mod for 433MHz [71]
Transmitters
Connects to any PPM radio via trainer-port.
- ImmersionRC EzUHF transmitter - 433 MHz frequency band, 200mW or 600mW power-mode, 9-12V prototype model
- Dragon Link transmitter - Transmits at 433MHz, 500mW [72]
- Thomas Scherrer OZ2CPU UHF system - Many hardware revisions, hard to keep track
Receivers
- ImmersionRC EzUHF receiver - 8-channel receiver, signal diversity, 50A current-sensor, 10 Hz GPS
- Dragon Link receiver
- Futaba R149DP 72 MHz [73]
- Corona RP8D1 35 MHz, 4 meter antenna [74] [75] [76] [77]
- Corona RP6D1 35 MHz [78] [79]
Other
- ImmersionRC EzAntennaTracker - Uses GPS-coordinates from EzOSD inserted in the right audio channel
Plane
Airplanes
- Ritewing Zephyr - Foam wing base, glass fiber rods, and winglets [80] [81]
- Multiplex Easystar - Simple glider-plane [82]
- ParkZone Radian PNP - Glider, prop in front, huge easy to spot [83]
- EasyStar - Cross between glider and sport plane, 3-channel, easy to modify [84]
- AXN Clouds Fly - Great glider, limited space for equipment
- Ele Bee - Flying wings [85]
Motor
- Hacker A30-10L V2 [86]
- Turnigy 35-36B 1300Kv Outrunner [87] - Great for Maxi Swift [88]
- Turnigy AerodriveXp SK Series 35-36 1400Kv 550w [89] [90]
ESC
- Graupner Brushless Control 70 BEC [91]
- Hacker X-55 SB Pro Brushless Motor Speed Controller ESC 55A
- Turnigy Plush 60A ESC [92] - Great for 4S
- Turnigy Plush 40A Speed Controller [93] - Great for 3S
Blades
- Turnigy 10x6 folding blades
- Aeronaut CAM foldering carbon propellers
- Aeronaut CAMcarbon Power-Prop 10"x7
- TGS 10x6F Precision Folding propeller [94] [95]
- Aeronaut CAMcarbon 9"x7 folding prop blades [96]
Spinner
- Aeronaut Propadapter [97]
Motor mount
- Ebay high-strength boat motor mount [98]
Servos
- Hitec HS-645MG [99]
- Gaupner Servo DES 708 BB MG [100] [101]
- Turnigy 380MAX Micro Servo [102]
- Blue Bird BMS-661DMG+HS Super Fast Digital Servo (MG) 6.4kg .08sec 46.5g [103] [104]
Batteries
- Turnigy nano-tech 4S 3300mAh (2x)
- Turnigy S3 2200 mAh
- Zippy S3 2200 mAH - Cheap Hobbyking packs
- Flightmax S3 2200 mAh [105]
Charger
- Bantam BC-6 - Korean, high quality
Materials
- Laminate - Apply to foam wing to give it a outer strength and cover for paint
- Riteweave - Flass fiber mesh to add strength over open cuts in the foam [106]
Glue
- 3M90 adhesive - Spray adhesive for base to add laminate
- Zap-a-Gap CA glue - For sparing bars in wings, or Gorilla glue
- Gorilla glue brown - Glue for wing and sparing bars, activates by adding water
- Goop, Bison Polymax - Fasten winglets
- Epoxy adhesive - Properly fasten the motor mount plate to the surrounding foam
Tape
- 3M Mailing & Storage tape - Mount elevons to the airframe, 1/3 on the elevon, UV resistant [107]
Shops
- readymaderc.com - Offer a range of products from the main FPV manufacturers
- nghobbies.com - FPV gear
- rangevideo.com - FPV gear
- dpcav.com - FPV gear and electronics
- hobbyking.com - All-around-supplier of batteries, servos, motors, cables, wires, rods
- hobbywireless.com - Everything cameras and transmitters
- der-schweighofer.at - Austrian shop
- stockrc.com - Selection of various FPV equipment
- electronicarc.com - Huge selection
- der-schweighofer.at - Austria hobby show
- electrocwingman.com - Great deal on aeronaut props
- foxtechfpv.com - Manufacturer and shop in China
Tools
- Flying wing CG calculator - Great for finding CG [108]