This week I overcame the challenge that is making foam wings out of sheets of foam... hard to describe, you'll just have to watch it : )
I finally got it down and cut out two wings for the Raptor, taped em' up and got the electronics ready...See you next week!
-Trent
Hi Everyone,
If you are developing some GPS based applications maybe you know, GPS data protocol is serial and %90 of data is just garbage. You have to listen it every time, data parsing a headache and impossible to making other time critical applications in same time.
I'm glad to announce the Navigatron - I2C GPS solution :)
Navigatron is an Arduino based board with GPS and backup battery. It is including Atmega328, FTDI port and 16mHz clock and working with 3.3-5v (you must replace the backup battery charge diode with a blue led for 5v applications)
I wrote my own I2C codes and tried other I2C project since 1 years but they wasn't enough easy. Most of I2C GPS codes sending all values in a single stream. Then 2 month before a guy (EOS Bandit) from MultiWii forum find a simple and perfect solution. His code simulating a real I2C device and you can access each register address separately.
Navigatron is coming with EOS Bandit's firmware with MultiWii 2.0 support. It is an opensource and you can replace the firmware for your requirements.
It is also storing/calculating way points and giving the direction and distance for you. This is perfect solution for low speed microprocessor based UAV applications because just you need a magnetic compass value for finding the way to home(or waypoint)
Here is the current I2C register addresses of gps values:
I2C_GPS_ADDRESS 0x20
I2C_GPS_STATUS 0x00 //(Read only)
---I2C_GPS_STATUS_NEW_DATA 0x01
---I2C_GPS_STATUS_2DFIX 0x02
---I2C_GPS_STATUS_3DFIX 0x04
---I2C_GPS_STATUS_WP_REACHED 0x08 //Active waypoint has been reached (not cleared until new waypoint is set)
---I2C_GPS_STATUS_NUMSATS 0xF0
I2C_GPS_COMMAND 0x01 //(write only)
---I2C_GPS_COMMAND_POSHOLD 0x01 //copy current position to internal target location register
---I2C_GPS_COMMAND_RESUME 0x02 //copy last active WP to internal target location register
---define I2C_GPS_COMMAND_SET_WP 0x04 //copy current position to given WP
---define I2C_GPS_COMMAND_ACTIVATE_WP 0x08 //copy given WP position to internal target location register
---define I2C_GPS_COMMAND_WP 0xF0 //Waypoint number
I2C_GPS_WP_REG 0x06 //Waypoint register (Read only)
---I2C_GPS_WP_REG_ACTIVE 0x0F //Active Waypoint
---define I2C_GPS_WP_REG_PERVIOUS 0xF0 //pervious Waypoint
=== Values ===
I2C_GPS_GROUND_SPEED 0x07 //GPS ground speed in m/s*100 (uint16_t) (Read Only)
I2C_GPS_ALTITUDE 0x09 //GPS altitude in meters (uint16_t) (Read Only)
I2C_GPS_TIME 0x0b //UTC Time from GPS in hhmmss.sss * 100 (uint32_t)(unneccesary precision) (Read Only)
I2C_GPS_DISTANCE 0x0f //Distance between current pos and internal target location register in meters (uint16_t) (Read Only)
I2C_GPS_DIRECTION 0x11 //direction towards interal target location reg from current position (+/- 180 degree) (read Only)
I2C_GPS_LOCATION 0x13 //current position (8 bytes, lat and lon, 1 degree = 10 000 000 (read only)
I2C_GPS_WP0 0x1B //Waypoint 0 used for RTH location (R/W)
I2C_GPS_WP1 0x23
I2C_GPS_WP2 0x2B
I2C_GPS_WP3 0x33
I2C_GPS_WP4 0x3B
I2C_GPS_WP5 0x43
I2C_GPS_WP6 0x4B
I2C_GPS_WP7 0x53
I2C_GPS_WP8 0x5B
I2C_GPS_WP9 0x63
I2C_GPS_WP10 0x6B
I2C_GPS_WP11 0x73
I2C_GPS_WP12 0x7B
I2C_GPS_WP13 0x83
I2C_GPS_WP14 0x8B
I2C_GPS_WP15 0x93
I2C_GPS_WP_NAV_PAR1 0x9B //Waypoint navigation parameter 1
---I2C_GPS_WP_NAV_PAR1_REACH_LIMIT 0x0F //lover 4 bit, waypoint reached distance
I2C_GPS_GROUND_COURSE 0x9C //GPS ground course (uint16_t)
For Schematic/Sample Codes and other details: http://www.flytron.com/sensors/180-i2c-gps-for-multiwii-and-others.html
Have a nice weekend
Melih
So after reading through the comments on this post, it got me thinking about the possibility of using the MinimOSD, or soon to be released jDrones MiniOSD, on the ground to have one less item up in the air. The appeal of keeping the aircraft light and a little less expensive, in the case of a flyaway or bad crash, makes me think this could be a good idea for those of us that have a more restrictive budget for UAV's.
Doing further research into what I need to get to be able to use an APM2 with an OSD, I decided to eventually buy the MinimOSD when I have the funds (or jDrones MiniOSD if it gets released). I then found this post about how the code was ported over to another different OSD hardware.
Then I remembered that I have one of these in my box of stuff I haven't gotten around to doing anything with.
There are many more capable people than me that could probably do this but how difficult would it be to take the code that runs on the MinimOSD and port it over to Arduino to run on the Nootropic Video Experimenter shield? The guy that produces these shields did a nice write up of displaying GPS data using this shield so it seems like it would be possible to do something similar.
http://nootropicdesign.com/projectlab/2011/05/20/overlay-gps-on-video/
Using this set of hardware, you could easily interface it with the video out of the video receiver in between the receiver and goggles/LCD and then tap into the ground station XBee to pull out the telemetry stream. Would it be difficult to port the code over? I've never done something like that before so I'm curious to find out if this is something that would be useful in any way so I have one less thing that could go wrong in the air.
After playing cat & mouse with the 3DR landing gear at the online store, I was finally able to the last two pairs before they sold out again. This however, wasn't before a lengthy wait for them to be listed. About a week ago, I headed over to my local hobby shop and grabbed a helicopter landing set for $14.99. I didn't have to do much to get it to fit on the 3DR frame and I have to say, I very much like the result. The copter is about an inch and a half lower but awesome .
Pics
The always great Robots Podcast has a particularly good episode this week, from one of the co-founders of Kiva, the warehouse robotics company that Amazon just agreed to buy for $775 million. He also does some very cool stuff with quadcopters, which you may have seen some videos of but he explains a lot more in the interview.
From the description:
Raffaello D’Andrea is Professor of Dynamic Systems and Control at ETH Zürich, and co-founder and chief technical advisor for US company Kiva Systems. His research focus is pushing the boundary of autonomous systems capabilities, with an emphasis on adaptation and learning.
He tells us about his first impressions following one of the biggest deals in the history of robotics, the acquisition of Kiva Systems by Amazon for an estimated USD 775M. D’Andrea was on the show in 2008 to talk about Kiva’s pioneering warehouse automation solution, which uses fleets of up to 1000 mobile robots to streamline the process of picking, packing, and shipping e-commerce products. We also look at work in dynamic systems out of his lab, including projects from the Flying Machine Arena (listen to a previous interview on the Distributed Flight Array) and a recent collaboration with Gramazio & Kohler on the construction of undulated brick walls using quadrocopters. We then dive into the Art scene with projects such as the Blind Juggling Machine, the Robotic Chair and Tableand finally take a step back to discuss the importance of fundamental research in engineering and strategies for translating knowledge in complex systems to industry.
From Forbes:
Stratasys and Optomec Inc. today announced that the companies have successfully completed a joint development project to merge 3D printing and printed electronics to create the world’s first fully printed hybrid structure.
The first project is a “smart wing” for an unmanned aerial vehicle (UAV) model with functional electronics printed right on the wing structure.
An Optomec Aerosol Jet system was used to print a conformal sensor, antenna and circuitry directly onto the wing of a UAV model. The wing was 3D printed with the Stratasys Fused Deposition Modeling (FDM) process. The electrical and sensor designs were provided by Aurora Flight Sciences, a supplier of UAVs.
We envision many potential applications of the Stratasys-Optomec approach for hybrid direct digital manufacturing,” said David Kordonowy, who leads Aurora Flight Sciences’ Aerostructures Research Group. “The ability to fabricate functional electronics into complex-shaped structures using additive manufacturing can allow UAVs to be built more quickly, with more customization, potentially closer to the field where they’re needed. All these benefits can lead to efficient, cost-effective fielded vehicles.”
The combination of FDM 3D printing and printed electronics technologies can provide benefits over traditional prototyping, manufacturing and field repair processes. Performance and functionality of products can be improved in two ways: 3D printers enable lighter weight mechanical structures; and conformal electronics printed directly onto the structure frees up space for additional payload.
If you follow the 3D Robotics Twitter feed, you'll have seen that APM 2 production is underway again! The hard-to-get pressure sensors arrived, and shipments will begin again next week. At this point, the supply chain shortages should be over, so we expect APM 2 to be continually in stock once all the pre-orders are filled in a week or two. Yay!
Remember, APM 2 is now available with an external GPS option or with the headers unsoldered, if you want to use different ones than the defaults.
(For the production gurus out there, be reassured that there is a layer of antistatic foam between each of those in-progress APM stacks in the picture)
Another good one from Hackaday:
The smooth curves of this integrated landing pad makes us thing the frame was cut either with a CNC device or a utility-knife wielding ninja. Two of the three motor supports look just like this one, but the third has a hinged mounting bracket attached to a servo motor. This way the propeller can be tilted around an axis running parallel to the support arm. We’d bet this feature is mainly for adjusting the yaw of the aircraft.
The video comments mention that this can hover when the throttle is at 45%, showing that there’s a lot lift available when needed. That is until you really weigh it down byadding plastic cages around the propellers. It’s kind of neat to see the thing ‘sticking’ to the ceiling at the end of that clip by driving the throttle wide open and using the cages as top-sided landing gear.
Hi all.
I have made a long run at 'human flight level'.
The machine is basically EasyStar with FLEXIPILOT but the discussion applies to anybody using typical hobby grade ESC. The plane is equipped with RAY 2845 inrunner motor and RAY 25 ESC, same as JETI ECO 25. Runs on Kokam 4Ah SPLB 30C. The plane is equipped with humidity and external temperature sensor, as well as additional temperature sensor for barometer compensation.
The flight took place with average cruise speed 12m/s (46km/h), the wind was around 1m/s (4km/h) and took place late afternoon.
On one hand the humidity was increasing, very slightly decreasing lift conditions:
At the same time the temperature was dropping, making air thicker, improving lift conditions:
This meant that while Standard Altitude depending only on pressure was contant,
density altitude decreased by negligible 50m (lower is better, less is more and time is infinite):
Overall, thanks to very calm weather and excellent PID tuning also, long term altihold was within one meter (slightly above my head). The spike at the middle was temporary switch to RETHOME for pilot's amusement (got bored).
As time passed by, battery voltage was dropping
And total energy of the plane (kinetic+potential divided by mass) was like this (constant):
This meant, that with constant plane geometry and aerodynamics, roughly the same amount of power had to be injected to the engine - it was autopilot's job.
Indeed the PWM throttle output signal (10000=1ms) was rising gradually, 'ordering more ESC output' in order to compensate for dropping voltage:
Power injected is P=U*I, and one would expect P to be constant, yet... here comes the surprise
Looks like electric power input to the motor was jagged, because the ESC could command only larger jumps of throttle... You can see amperage sensor confirming the stepped amperage increase, compensating for smooth voltage drop:
As a final confirmation, the RPM sensor revealed that the throttle was basically jumping +/-60RPM what could be even heard (now I know where does this sound comes from)
if we assume that the whole span of RPM control of this ESC is some 0-15000RPM, you get 15000/60=barely 250 steps, what is some 8 bits! To be more precise, I would describe the situation, it is not ESC having problem with RPM hold (which is not even trying to do) but rather having stepped amperage output control that also drifts a little with voltage. Since this UAV flies only between 10000 and 14000 RPM (below 9000RPM the motor generates only a tiny thrust) you actually have 4/15*250=67 possible and useful output amperage values.
By sounds that I hear from the propeller, probably all popular ESC brands behave less or more like this (what few people have witnessed because few ppl are doing routine loiters that low). .
Now since you are at the end of this analysis, a question for 10 intergalactic points:
Which ESC behave like this and how to identify those that do better?
From Hackaday:
[Mike Field] got his hands on this Syma S107 helicopter with the intention of hacking it. After playing around with it for a while he set out to build his own infrared controller for the toy. It seems there is some protocol information about it published in various forum posts, but he decided it would be more fun to figure it out for himself.
He started off trying to capture the IR signals using Adafruit’s tutorial which has come in handy on a number of other projects. He could get his television remote to register, but not the toy’s controller. This didn’t stop fun, instead he tore open the controller and grabbed a logic sniffer to see what’s being pushed to the IR LEDs. The signals are a bit curious. It seems two different packets are sent with each command which [Mike] thinks is for use with two different models of the toy. In addition to that the frames are not synchronized. But a bit of 10 MHz sampling helped him to figure everything out, and he believes he’s got a more accurate version of the protocol than had previously been discovered. To prove it he developed an FPGA-based controller using VHDL which he shows off in the clip after the break.
Thanks for all the hard work Diydrones team! I've finally got my quad flying and it is a lot of fun. I am on to the tuning and testing stage, burned through a bunch of batteries and props yesterday. :) oops. Being a complete newb to the RC scene, this build was pretty difficult but very rewarding. Teaching myself to fly has been great, and the last 3 months of work has paid off. Here are some details of my build, hopefully they may help someone out:
Replacement "Lowes Special Highrise" Landing Gear. Saves 40 grams. :) I suck at flying my quad, so I am always breaking stuff while learning. Yesterday I broke one of the landing gear and decided I wanted highrise but not wait for shipping. After building the new gear and comparing against the old landing gear I was surprised to see each was about 10 grams less weight. Around 40 total.
Frame: 3DR Quadcopter rev A
Telemetry: No
Controller: APM2
Motors: 880kv
Props: 10x4.5black, 10x4.5apc (worked great!), 12x4.5 (not very good for me)
ESC: Thunderbird 36
Battery: Turnigy 4000mah 3S
Sonar: XL-EZ0
Landing gear: Custom Lowes Special
Firmware: 2.5 from Mission Planner
Mode: X
PID Settings:
Defaults with RATE ROLL P = 0.105
I've had successful flights with all props with these settings, the 12" props definitely seems to introduce stab issues making the quad hard to control. The 10x4.5 and 10x4.7 from APC have been great giving me the most success. Now, a few mods that I've done to help fix bends, breaks, bruises after crashes or just make things more solid:
I put a couple of small washers under the motor to distribute weight and help stop the aluminum from bending. I've found it helps keep the motors straight.
I found small diameter aluminum tubing at Lowes, cut this into 3/4" sections and used over bolt to help keep frame from bending. Tubing
Added a few extra washers here and there to help distribute weight when tightening
Mounted the APM using faucet o-rings from Lowes. O-ring
I can't remeber the exact size. APM2 Mount
Landing gear parts:
Old gear: ~23g with hardware
New gear: 14g with foam
1) 1/2"w x 36"l aluminum strip from Lowes 3' bar
2) section of pipe insulation from Lowes
3) zipties
I hope to post some "in flight" pictures soon! Thanks,
JP
This headline appears in The Times newspaper, published in London, on Friday 23 March in a feature about the growth of US police forces using unmanned aircraft. (Although the article is behind a paywall, it is reprinted in the Australian here). The article goes on to mention diydrones.com as the 'leading website for enthusiasts.. for a growing army of amateurs who are building drones fitted with autopilot systems...'. It charts the development of small drones for a variety of applications and sights their use to replace humans for dull, dirty and dangerous jobs.
AerVironment gets a mention and a video of its Cube foldable multicopter and there is a quote from Peter W.Singer of the Brooking Institution.
Peter
A review of a human powered ornithopter that really worked shows how hard the problem would be for anything where a human was the main source of power. Even with an exoskeleton augmentation, the power in any affordable batteries would be too little & the weight of the batteries would make human power even less important.
Better results have been achieved by human powered propellers than ornithopters.
& technology hasn't really changed since then.
Now that someone has revived the idea, a lot of people are again going to be in a race to build the 1st human augmented ultralight. The trick is ultralights & gliders have been around forever. Electric ultralights have been around forever.
The human powered ornithopter that actually flew needed the biggest wing possible. It could only be flown in the deadest calm. It still needed a tow on the ground. It was hardly a recycled kite.
Surely many skinny unmarried men have already tried extending their flight time with human power only to find it negligible or the amount of battery mass required to augment the human eliminated any benefit of human augmentation.
If it's battery augmentation of human power you want, the best route is a ground based tow vehicle pulling a human powered glider. The batteries would give it a good starting altitude. It could be RC in that the human controlled it remotely. Then it could be autonomous. The human would then unhook & take over providing power in flight, maybe getting a longer glide time.
Human powered airplanes go for around $1 million & take a lot of grad students to build, of course.
Sigh. Prepare for loads of credulous coverage, matching the wave of reporting on the Pirate Bay's stoned suggestion that "we're going to use, er....GPS drones!....to file-trade from the sky. With Raspberry Pi."
Ok , this is what i've been up to for the past 6 months besides ignoring my family working and getting little sleep . took me about 300 hrs of CFD time on my cluster alone plus a whole lot of cad work .the flight surfaces are well trimmed through the earlier iterations of the early techpod .I found the airflow around the bottom side of the wing root towards the tailing edge very turbulent forming a large "bubble' illustrated here
this would seem endemic to this aircraft configuration . I was able to eliminate it by reiterating the fillet and wing root area and slightly increasing the incidence . I was able to get the drag down to about .8 lbs @ 60 mph
I have a prototype on order and should be receiving it in about a month . and here is the part where you come in . if all goes well with the prototype i can order a large batch . Only thing is the minimum order comes to $40,000 . I work for a living so i don't have that kinda scratch . I do have about $15000 saved up however . anyway , I;m thinking about using kickstater.com . I would like to get a feel for how many people may be interested in pledging . the kits will go for about $250 retail and i will have ready to flys as well pledgers will get a deep discount.throw me a pm or give me a shout here if your interested . I will post pics of it as soon as it comes in .here are the specs
IEEE Spectrum got executives of the leading closed source and open source robotics companies to debate their models at a cocktail party. Here's an excerpt, but it's worth reading the whole thing. [You already know where I come down on this issue]
[At left, iRobot CEO Colin] Angle suggested that Willow Garage's approach of freely providing such a key component as the robotic operating system -- and the extensive libraries that go with ROS, not to mention its source code -- was tantamount to letting the biggest consumer electronics giants gobble up any mass market applications and re-market them globally at low cost because they already have (or could easily reverse-engineer) the hardware, could produce it cheaply, the operating system was free courtesy of ROS, and the only real cost was the acquisition of the application.
Angle thought that the approach was dangerous and led to losing a potentially U.S./European market to offshore commodity conglomerates. (The dangers of losing trade secrets to foreign conglomerates was the subject of a recentBloomberg Businessweek issue.) He added, "Robotics innovation represents a tremendous opportunity for economic growth akin to automobiles, aerospace, and information technology. If we are to freely share our 'intellectual capital' on the open market we risk losing the economic engine that will advance our economies and send growth and jobs overseas."
It was [Willow Garage executive Robert] Bauer's turn now, and he argued that Willow Garage's objectives were to stimulate the industry by enabling participants to not have to reinvent the many cross-science elements of robotics ventures; to reuse software under the premise that by so doing it saves developer time and allows researchers to focus on research. By giving them free access to the tools, libraries, and simulation capabilities of ROS, Willow Garage hopes to advance the state-of-the-art in autonomous robotics technologies -- and the commercial applications will follow.
The context is not so legal. But an interesting idea, even if they seem to have little idea of how to implement or how to manage power :-).
some extracts:
"Low Orbit Server Stations"
"With the development of GPS controlled drones, far-reaching cheap radio equipment and tiny new computers like the Raspberry Pi, we're going to experiment with sending out some small drones that will float some kilometres up in the air."
Hi Guys,
The title is a little bit ambitious but i guess no one tried to lift a GoPro with a 140gr Micro Quadrocopter before :D
The throttle was %80 when flying with half drained 2S LiPO battery, this is why it is a little bit aggressive.
This is my micro quadro setup
Controller:Opensource OpenLRS Multi receiver with Gyro and Acc with onboard radio receiver
Firmware: MultiWii v1.9 (modified for OpenLRS onboard receiver)
Frame: MQ-200 microquad frame
Props: HK 5x3 (black/red) props.
ESCs: FL6A Fast PWM 6A ESC (Hobby King 6A with firware update)
Motors: HK 10gr
Thanks
Melih
"Part nomadic infrastructure and part robotic swarm, we have rebuilt and programmed the drones to broadcast their own local Wi-Fi network as a form of aerial Napster. They swarm into formation, broadcasting their pirate network, and then disperse, escaping detection, only to reform elsewhere,” says the group describing their creation."(Source)
I think that may be more concept than reality, but they do seem to fly nicely. It was for a festival last year.
If you've been wanting to understand a bit more about PID controllers, unit 5 of Sebastian Thrun's Udacity course "Programming a Robotic Car" has some nice coverage of that topic and the theory behind it.
