Would it be easier to build a quadcopter? Seems like stabilisation would be easier. This thread says that a helicopter autopilot is hard, but maybe doesn't consider a quadcopter: http://diydrones.com/forum/topics/will-ardupilot-work-with-a
Based on SPAD
- Fuselage made of aluminum angle
- Covered with heatshrink plastic
- wings made of coroplast
Buy a kit with xmtr, rcvr, and servos. How many channels? Throttle, roll, pitch, yaw, failsafe mux, kill switch?. 6? http://www.greathobbies.com/productinfo/?prod_id=SPM6600
Looks like it won't interfere with the XBee modules.
mux so that RC takes priority over autonomous - but what about other users of the frequency who may be a long way from base but near the plane?
Might be a good idea to get one of those systems that guarantees no interference.
You'll also need:
- A six or seven channel RC transmitter and receiver, with at least one toggle switch (ideally three-position but two-position will work, too, although you will have to mix channels to have access to both autopilot modes in the air), such as the Futaba 7C.
- Some servos (at least three for ArduPilot 1.0; at least two for ArduPilot 2.x) and at least three female-to-female servo cables to connect the RC receiver to ArduPilot.
What you need to make a fully-functional autopilot:
- ArduPilot board - 25.95USD from Sparkfun
- Shield expansion kit with airspeed sensor - 36USD from DIYDrones
- GPS module (uBlox5 recommended) - 159.95USD from Sparkfun, note that this includes a cellular modem
- XY and Z sensors - 95USD from Sparkfun
- FTDI cable for programming
- [Optional] Two Xbee modules for wireless telemetry: This one with this adapter in the air and this one with this antenna and this adapter board (or, even better, our ArduStation) on the ground/laptop side - Included with GPS
Our approach will be a bit different.
Start with a SeeeDuino Mega (4 UARTs!), add an ArduIMU for AHRS, an XBee or cell module for telemetry and commands, a $20 GPS from Factory Direct, and a failsafe mux for full manual control.
"ArduPilot is a full-featured autopilot based on the Arduino open-source hardware platform."
Ardupilot doesn't include an AHRS, and only has 1 UART, making it difficult to connect the ArduIMU, a GPS, and a radio.
Instead, use a SeeeDuino Mega with 4 UARTs, 70 digital IO, 16 DAC, 14 PWM.
Ben has a USB GPS adapter. We could either try to use Arduino USB host mode or open it up to get access to the serial lines.
USB to Serial GPS Here's a link to break out the GPS that comes with MS Streets and Trips.
It will talk nicely over a serial port.
GM862 Cellular Quad Band Module with GPS Slot for SIM.
Ben has a USB quad-band GSM adapter. If we can get Arduino USB host mode working we can use it.
I have this unit here Novatel MC950D Which works well for me.
To make it a bit cheaper and easier for the first iteration, we'll use XBee Pro 50mW modules.
The IMU includes a 3-axis accelerometer and a 3-axis gyro. ArduIMU
Maybe want one of these instead: ArduIMU V2
Question about connecting ArduIMU to ArduPilot. One response says that the ArduPilotMega will have the IMU built in and will be coming early 2010. This probably fits fine in our timeline - we probably won't be ready for such things until then.
Allows the RC system to take over control from the autonomous system. Uses one RC channel. http://store.diydrones.com/ProductDetails.asp?ProductCode=BR-0001-10
This functionality seems to be built in to ArduPilot.
I hear that brushless is the way to go.
Built into receiver?
Eventually, LiPo or LiFePO4.
To start, an 18V NiMH pack from an XS Cargo cordless drill.
It's probably not necessary to use separate supplies for the motor and electronics - just use a good switching regulator and lots of caps. Unless the motor won't handle 18V and a suitable regulator cannot be found? Could reconfigure the pack into two 8.4V packs in parallel (with one extra cell)
GPS, cell, RC
As long as the plane stays under 35 kg (77 lb) and is for recreational purposes, it's a model aircraft and not a UAV, despite our use of the term.
From CAR: UAV is "a power-driven aircraft, other than a model aircraft, that is designed to fly without a human operator on board"
Model aircraft is "an aircraft, the total weight of which does not exceed 35 kg (77.2 pounds), that is mechanically driven or launched into flight for recreational purposes and that is not designed to carry persons or other living creatures".
CAR says that model aircraft can't be flown into clouds and they can't interfere with aviation safety.
Transport Canada published this brochure about UAVs and the permits required for them. They need Special Flight Operation Certificates, which require way more planning and preparation for flights than is practical for something like this (routes, dates, times, location of obstacles).
The status (UAV vs model aircraft) of a particular aircraft is not determined by the mode of control (autonomous vs radio) but by its weight and purpose.
Are we allowed to fly planes in any field we like?
How it's made
- UART0: PC communication
- UART1: GPS
- UART2: ArduIMU
- UART3: XBee
How to configure: http://www.humboldt.edu/~cm19/XBee%20setup.pdf
Our PAN ID is 4A6.