Another round of code dump, I've been playing with an A.R. Drone, following is a simple autopilot implementation which uses an overhead camera for tracking and guidance. The way this whole setup works is, I've glued two circles on top of the drone, an overhead camera tracks these two circles. circle which sits at the center of the drone gives its location, combined with the pink/reddish circle that sits towards the front of the drone, taking the angle between the centers of the circles gives Once you know the position and orientation of the drone, all it takes is simple vector math to get it follow a pre-defined path. Calculations assume origin is at the center of the frame, +x going towards the right of the frame and +y going up the frame. assumes origin is at the top left corner. cam coordinates to world coordinates and vice versa. locate-circle takes the frame from the camera, a copy of the frame converted to HSV color space and lower/upper limits (Hue

Saturation Value) for the color we are trying to isolate. the color range using in-range-s, it returns a binary image in which pixels that fall with in the range are white rest iseroding and then dilating the image removes noise (specks of white from the white tape on the floor.) Finally we find the contours of the match using bounding-rects calculate its center and return it or nil if there is no match. locate-marker tries to match both markers, draws some debug information, shows the frame and returns a vector of vector-2d points when there is match. start-cam is where we continuously locate the marker, calculate the angle between the markers and update the drone-loc atom until These define two PID controllers, one to keep the altitude and another one to keep the orientation at their set points (1 meter above ground To fly to a certain point on the map, we begin by drawing a unit vector to the target (to-target) as long as drone is pointing

towards 0 degrees (direction of +x) we can use the vectors' x component as pitch and y component as roll but since this is a quadrotor which can move in any direction without turning towards the target, we rotate to-target using the drones current orientation that allows us to map x , y to picth , roll whatever theFinally we scale local-target using a PID controller so it slows down as it approaches the target. If you are familiar with Craig Reynolds steering behaviors this ishow much does an uav cost basically the arrive behavior with a caveat, what I don't track is themini drones with camera for sale drones' speed, even though local-target gets smaller as itmacdev drone dx anleitung

approaches the target it does not apply any breaking so if it is travelling from one end of the map to the other it will fly past the target and come back to it. To fly to a point on the map, we send an arrive command every 20 milliseconds until we are within a desired distance from the target. To take off, we reset the communication watch dog, tell drone to start sending telemetry (battery level, altitude, yaw etc.) back, send a trim command toparrot ar drone firebox let it calibrate itself then a takeoff command to take off.parrot ar drone idealo To land, we send a hover command which levels the drone and send landmq-27 dragonfire drone have camera command bunch of times (since communication is done over UDP sending

it once works 90% of the time) and stop the thread that listens for navigation take a list of waypoint accuracy pairs and puts all ofIt will return a sequence that will take off, wait until the drone is half a meter in the air, start flying towards a waypoint until it is within given accuracy/distance and move on to theFinally when it goes through all the waypoints it will Probe and Pick SetIt has blown away every drone expert we've talked to. It's not just a toy: it's a phenomenal piece of engineering that manages to solve some very difficult software problems in order to take flight. Hidden beneath the foam fascia lies some very sophisticated electronics, all of which makes flying the quadricopter very seamless. We were quite interested in seeing exactly what components Parrot used to make their awesome flying device. This holiday season, let’s encourage repair and reuse rather than buying more things we don’t need and won’t last. With our friends at Wired, we’re running a toy repair contest.

We’re giving away a ton of awesome tools, so make sure to get started on your entry right away! This teardown is not a repair guide. To repair your Parrot AR.Drone, use our service manual.Drone remote-controlled quadricopter recently landed on our teardown table. What's cooler than one quadricopter? Two quadricopters, of course! Drone comes with two hulls: an indoor unit with guards over the propellers (grey/white) and an outdoor unit (orange/blue). You might notice the lack of a controller with this awesome gadget. That's because the controls are managed via an iPhone, iPod Touch, or iPad by using AR.Free Flight, an application available for download in the Apple App Store. Android users can now enjoy the AR.Drone Android app from the Market!opening up the AR.Drone doesn't even require a screwdriver. (Compare this with some recent devices we have torn down!) The hull is attached to the body by a pair of magnets; one in the hull and one on the body. Much of the AR.

Drone's body is made of expanded polypropylene (EPP), a common substance that is both extremely light and easily manufactured into complex shapes. The 1000mAh 11.1V lithium polymer battery is attached via a connector, making it delightfully easy to remove. The second connector is a balance charge connector, which ensures that each of the three battery cells is charging equally, thus optimizing capacity and prolonging battery life. The battery contains a protection circuit module, which prevents it from discharging too rapidly, over charging, or short circuiting. Parrot claims the battery will only last about 12 minutes after a full charge, which takes around 90 minutes. Drone out to the park with only one battery won't get you much play time, unfortunately. Next, we turn to the underside of the quadricopter. After removing four T6 Torx screws, the lower plate can be lifted off to reveal the motherboard and navigation board. The navigation board is connected to the motherboard by eight pins and comes out without any hassle.

The two large mesh cylinders make up the ultrasound altimeter, which stabilizes the quadricopter within 6 meters of the ground. The back side of the navigation board contains the Microchip PIC24HJ16GP304 40MHZ 16-bit microprocessor. The MEMS gyroscope, the Invensense IDG 500, is also found on this board. Parrot 6 ARM9 468 MHz processor. ROCm Atheros AR6102G-BM2D b/g Wi-Fi module. Each propeller assembly is made up of the propeller blade, gear, motor and motor controller board. These are not your run-of-the-mill propellers. The design team behind these won a micro drone design contest put on by the French Army. The propellers spin in different directions depending on the side they are mounted on, and are marked either C (clockwise) or A (anti-clockwise). The propeller blade and gear are held in place by a small circlip on a stainless steel shaft. Parrot sells a special circlip removal tool, but we opted for a pick we had lying around the office.

These little guys can definitely go flying if you're not careful. Luckily, they come as part of two different replacement parts packages available directly from Parrot. The four motors and their electronic controllers are each held to the central cross by six screws and a connector. Each brushless motor runs at 28,000 RPM while the AR.Drone is hovering, and as fast as 41,400 during full acceleration. The speed of the motor is managed by the electronic controller, which includes an 8-bit microcontroller and a 10-bit ADC. The arduous task of peeling the protection blister from the body reveals the camera ribbon cable and the second magnet that holds the hull in place. A little bit of prying and the front-facing VGA camera comes right off. The 93 degree wide-angle camera can stream its video and images directly to your iPhone, iPad, or iPod Touch. With a resolution of 640x480 pixels, we doubt anyone will be filming HD movies with the AR. With Augmented Reality, objects captured by the camera become part of the AR.

The central cross easily pulls right out of the foam shell. The two sets of wires in the central cross are responsible for controlling and providing power to the four motors. The tubes of the cross are made of carbon fiber to save weight and provide plenty of structural rigidity. The other plastic pieces are made of polyamide 6,6 (PA66), more commonly known as nylon. Yes, there are different variations of nylon, but it's not necessary to explain the differences between condensation and open-ring polymerization right now. Let's just get back to tearing down the AR.Drone Repairability: 9 out of 10 (10 is easiest to repair). The battery and upper case come off easily without removing a single screw. Almost everything is attached via ribbon cable connectors and screws, making replacement much more feasible. Parrot provides replacement parts and repair videos for common problems. Repair wouldn't be very easy without both of these. The c-clips on each propeller assembly are very hard to remove without the correct tool.