tag:blogger.com,1999:blog-90383734683979006662011-08-02T18:52:43.186+02:00Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.comBlogger781100tag:blogger.com,1999:blog-9038373468397900666.post-33640339300434943922010-10-21T23:29:00.005+02:002010-10-21T23:34:58.261+02:00

This is a protocol converter for I2C to PPM. It allows the use of standard ESC controler on Mikrokopter or similar. One of the major drawback of I2C currently, is in case of severe failure on one controller, you may impact all other controllers connected to the I2C bus and lost all motors.Choosing PPM is more reliable, as each controller is connected separately, it may not interfere with others

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-9612950360198575192010-10-09T10:47:00.007+02:002010-10-09T22:03:03.691+02:00

This is an update to my previous measurements and comments on DSSS/FHSSS technology:Some spektrum measurementsRecently I had problems with transmission video. It looks that some videos TX in 900 Mhz or 1.2-1.3Ghz band may generate harmonics on the 2.4Ghz band. See this thread:http://www.rcgroups.com/forums/showthread.php?t=1311059So it may be very dangerous if you switch ON your RC equipment *

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-71579748786447418062010-06-11T18:48:00.006+02:002010-10-21T23:42:25.919+02:00

A new version of the serializer is ready. It features:* channels from receiver are serialize on one wire* Compatible with Mikrokopter electronic and more RC receivers* Neutre stable on all channels* available in 8 or 12 channels (PPM8 ou PPM12)* with external crystal for better temperature stability* all channel entries are protectedYou can buy it at the shop www.flash-rc.com in Mikrokopter

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-56373822253080999962010-04-12T17:18:00.009+02:002010-04-12T19:12:38.587+02:00

It has been a while since I have updated the blog. In fact, I was waiting for a supplier to cut the aluminium plate for the transmitter. But unluckily, the supplier could'nt do the job after 3 months. This is a bad news :(. So I now have to find another solution, or do it myself (a good method also). Meanwhile, I have been working on a PPM serializer for Mikrokopters. It is now finished and

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-20716222092887452292010-01-24T23:41:00.004+01:002010-01-24T23:47:44.637+01:00

To bend aluminium for the enclosure, I built a simple basic machine make with plywood and some metallic rigidifiers. With the tube installed, the round corner is 10mm radius, which is exactly what is need for the transmitter enclosure. The thickness of the alu should be less or equal than 1mm. Some pictures below:

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-4710731744082287132010-01-24T23:31:00.007+01:002010-01-24T23:51:02.957+01:00

The second corner:

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-63969624513540568072010-01-18T23:08:00.004+01:002010-01-18T23:21:07.798+01:00

Some update about the enclosure: changes of the trim buttons, add holes for loudspeaker, reduce hole size for lcd and sticks, add logo. Top and bottom faces are made with aluminium.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-5413720840678063032010-01-13T23:02:00.009+01:002010-01-18T23:21:59.307+01:00

This is transmitter for next version of the radio. It is made with aluminium 10/10, bended on the side with a "tube" technique. I'll explain in more details how to this bending. The up and down side are made from pcb epoxy with soldered corners.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-60774534949396010542010-01-09T00:09:00.006+01:002010-01-09T00:16:07.679+01:00

Here is the ouptut of an Assan X8R6 receiver channel. The delay between pulse is 20msec, which is nice for most servos, and the max voltage is 3.4v. That may be unsufficient in some cases for old servos or regulator. Click on the picture for bigger image.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-9881192025089885072009-12-15T23:13:00.006+01:002009-12-15T23:28:33.922+01:00

Here is a new version of the Xmega bootloader which works at 115200 bps and with the buggy versions of Xmega that have some problems to be self flashed. This version has been tested on Xmega192A3 and stk600. The serial connection use the pins PORTD2 and PORTD3 for the rx/tx. Connection speed must be set to 115200 with avr-dude. Example of the command to use under linux to flash with avrdude (

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-83120093247348858812009-12-08T13:33:00.003+01:002009-12-08T13:41:33.182+01:00

I am happy to announce the new web site dedicated to RC@home projects. You'll retrieve most information from this blog plus new ones. It is structured to provide a quick access to the various parts if you are interested to build your own radio. This blog will continue to provide regular news on the subject and related:RC@home web site

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-18065134188458901052009-11-25T22:34:00.005+01:002009-11-25T22:43:16.084+01:00

A friend of my club (thanks Salvador) gave me his old Radios that he used years ago. They were made by Lextronic, a french electronic company. The company still exist, but the radio are not more sold. Simple, neat and strong.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-39511524148537948052009-11-11T23:31:00.007+01:002009-11-11T23:59:14.070+01:00

I received the prototype board (Stk600) for Atmel processor and started to play with it. The First step was to install a bootloader in the Xmega192a3.Hum, that was more complex than I thought. Xmega world is still very new and I discover several problems: avrdude program (to flash the xmega) does not work under linux (pdi does not work), and bigger problem, the Xmega 192a3 has a bug which

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-85259651867890884152009-10-25T21:49:00.005+01:002009-10-25T22:07:56.157+01:00

I received the new processor that may well be the basis of the next version of RCHome. It is an atXmega192A3. This processor looks very interesting for a radio transmitter because it has: * 16 Kbyte SRAM, which gives more spaces for the core of the software, * ADC 12bits (Analog to Digital) converter: for a best accuracy of stick inputs * tqfp 64 package, is "smt" technology, but should be

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-39760896582972966992009-09-22T23:27:00.005+02:002009-09-22T23:33:17.266+02:00

The schematic of Rchv2 is available here. It's made with "Kicad" which is a nice open source for electronics, schematic and PCB.. See kicad home page to get it.Thanks to Andreas Thorn for his help and contribution on this schematic.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-6075533892699162462009-09-13T23:43:00.004+02:002009-09-13T23:51:47.255+02:00

Some pictures of the Assan X8D module installation in a Futaba T12Z. Lock switch and led are located on the same side than antenna. PPM signal, + and - are taken from the back of the middle board which carries the trainer connector.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-66121197979971503532009-08-23T10:44:00.010+02:002009-08-26T13:09:24.482+02:00

Some more thought about what could be improved on most modern transmitters (including the nice new Robbe FX30):* programming usability: Some functions you will never know what they are used for, * no direct access to often used functions (on T12 you need to press 4 or 5times buttons just to change model),* no global view on what's happening on a servo channel,* limitations in switch cascading

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-16827906022065129762009-07-30T19:52:00.005+02:002009-07-30T20:03:37.248+02:00

The source code is now available on sourceforge under the rcopensource project, with GPLv2 license. You can view it, or retrieve it. To view it with web, go to gitweb.To retrieve, you'll need "git". Once "git" installed on your computer, to get it in read-only mode do:git clone git://rcopensource.git.sourceforge.net/gitroot/rcopensourceIf you want to contribute to the project, you are more than

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-76762600260098387432009-07-28T00:08:00.004+02:002009-07-28T00:22:55.076+02:00

The Hex image to flash and the PC gui application with examples is here. See README for more informations on how to flash and use.The short howto build the TX is still here.The sources (c++ , perl) will soon be available.Features:- 8 input ADC (sticks, pots),- more than 8 switches input,- 8 channels control,- configurable input (analog, switch)- configurable mixes, - reverse, limit, subtrim,

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-27655296801022387572009-07-18T21:47:00.003+02:002009-07-18T22:35:40.441+02:00

As the transmitter can now generates a PPM signal, I can use it as a "ppm Joystick" to any sofware simulator that take USB-PPM cable as input. For instance crrcsim or Phoenix, which are 2 really good sims, the first one for glider, and Phoenix for helico/planes. For crrcsim, the USB-Futaba connector cable works well, and for Phoenix there is a specific USB cable for Futaba. One both cables, it

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-30987890444698160352009-07-14T01:21:00.003+02:002009-07-18T21:46:51.217+02:00

Configuration file for aerobatic glider with flap,snap and butterfly:mcontrolmgr mcontrol=0 adc=0 calib_max=941 calib_min=76 calib_zero=504 mcontrolmgr mcontrol=1 adc=1 calib_max=898 calib_min=113 calib_zero=508 mcontrolmgr mcontrol=2 adc=2 calib_max=938 calib_min=76 calib_zero=475 mcontrolmgr mcontrol=3 adc=3 calib_max=979 calib_min=42 calib_zero=418 mcontrolmgr mswitch=5 pin=5 port=C

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-89738466993810023382009-07-14T00:36:00.006+02:002009-07-14T01:27:25.811+02:00

Yes.... that was the first flight with a more serious glider (jedi 4 home made), with 6 channels (2 ailerons + 2 flaps + elevator + rudder). The radio has been configured with several mixes and settings to work good enough for this model type. Here are some pictures, a video demo. The gliders has 6 channels, and a Assan mini 6ch receiver. Ok, do not do like me, use a more long range receiver. The

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-78672521528617097272009-07-11T23:43:00.009+02:002009-07-12T00:11:17.892+02:00

The next goal is to fly an aerobatic glider (4 wing servos, 2.50m wing span) with the summer version of RCHv2. Many changes and bug fixes have been done in the software. The USB-serial communication between PC and TX is very convenient, but can be a headache in some cases to debug. Hopefully, it now works pretty well, even with large model configuration.The PC configuration now support names for

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-40626452453773115952009-06-28T19:59:00.011+02:002009-06-28T22:50:05.433+02:00

Here are some screenshots of the application running on the PC. The radio is connected to the PC through a serial/usb cable. Each change done within this interface is applied immediately to the radio. Each model configuration can be stored/retrieved, they are just plain ASCII files. The first tab is for stick configuration, it allows to calibrate the stick and set various positions:Next tab

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-23086875983233695032009-06-13T20:26:00.010+02:002009-06-14T00:47:38.491+02:00

Today, I flew an Acromaster with the radio RCHv2 (5 servos). It worked like a charm. No interferences, no problems at all. I used the new program interface I developped for PC for programming on the field. I was a bit afraid to bring a PC to the field, because of the screen brightness and the Sun. But a neetbook with good screen, like the Samsung NC10, it's ok and very usable. Even if the

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-56813594754097809322009-05-26T20:18:00.011+02:002009-05-26T21:00:55.669+02:00

Withing few hours, provided you have the right components, you can build your own RC transmitter.First, an important component is the transmission itself. Any module with PPM signal as input can be used. For its low cost, I choosed the Assan module (Hack version X8D) with Assan receivers. Cool price and so far works fine. It is powered with 5V.The transmitter box is a very low cost transmitter

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com9tag:blogger.com,1999:blog-9038373468397900666.post-22907417956548358782009-05-26T20:01:00.005+02:002009-05-26T20:10:53.153+02:00

Last week-end first flight was smooth, even more than expected. The RCHv2 behaves exactly as I expected, even if the Transmitter power was very close to the limit (LM317 to produce 5V with only 5cells Nimh). The Assan module and the very small long range 4 channels receiver with a very short antenna (2cm) worked perfectly in the "Weasel" wing. No problem even when flying far from me (the wing is

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-11738926821328601302009-05-22T20:48:00.005+02:002009-05-22T23:53:24.721+02:00

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-66507084294675301322009-05-21T20:37:00.007+02:002009-05-21T21:41:07.526+02:00

Here is my new home made RC. It features 8 channels, a module 2.4Ghz Assan for transmission, configuration by PC, Micro SD 2GB, mixers, and settings fully configurable by the software.The transmitter box and sticks comes from low cost transmitter (could have been a RC joystick).The microprocessor is an AVR Atmega 644P, and the software is my own called RCHv2. My brand new flying wing "weasel"

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-25253367628348325222009-05-18T13:34:00.003+02:002009-05-18T14:32:58.437+02:00

I have been working hard on RCH recently. PC configuration through command line is working, model storage on SD card, and connection to PPM module. Stay tune for more details of this transmitter hack soon.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-26091027182366869642009-04-29T22:24:00.004+02:002009-04-29T22:37:55.739+02:00

AVR 1280, more flash, more SDRAM, and best of all more IOs .... This is the Arduino Mega. Cool...

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-74097959933906370702009-04-26T18:31:00.012+02:002009-04-26T22:09:40.436+02:00

All the configuration parameters can now be configured through a command line from the PC. Open a terminal window, and set a parameter.The design I choose intend to leave as much as possible flexibility to program a model. There is no preassociation of functions or mixers to any channel. Each possible function however has to be predefined, and is part of the software in the radio. For someone who

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-29343389055877771772009-03-25T20:03:00.003+01:002009-03-25T20:21:28.153+01:00

The software of RCHv2 is growing slowly by surely :) After many thoughts, I decided that the configuration of the mixers will be done through "xml" like commands. "xml" is a structured language to specify datas, very useful when datas start to be complex and a lot imbricated. And this is the case with the software of the radio, because I wanted it to be powerfull and generic enough to allow users

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-19330869515583075362009-03-03T20:28:00.014+01:002009-03-10T13:31:48.793+01:00

Last monday I had the opportunity with friends to do some measurements of spectrum on various 2.4Ghz modules. The initial intention was to measure the difference between 2.4Ghz antennas, but the environment (in a shop) reveals that it was impossible.So, no results about the antenna efficiency, but we could observe the spectrum of various transmitter. Thanks to flash-rc who makes this possible to

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-53953976302257936422009-02-27T23:55:00.005+01:002009-02-28T19:07:11.342+01:00

The transmitter case is almost finished. This is a prototype made with alumininium and epoxy plate (printed ciruit plate). If someone is interested, I can explain in another post how I built it. From the initial drawing, there have been some changes, such as dimensions.But it is close to what was designed with Styro , except the round corners. Knob unders the sticks are use both as trims, and as

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com4tag:blogger.com,1999:blog-9038373468397900666.post-37690144470573832562009-02-20T23:24:00.005+01:002009-02-21T23:55:04.260+01:00

After drawings, it is time to make some box in styro, to better feel the shape and how it will fit in hands. I made several trials. It's not easy to find the perfect balance betweeb size, shape, sexy look, good ergonomy, light weight, etc... The prototype will not be perfect for sure, but it will benefit to check the dimensions, size, and ergonomy. Let's hope it will work like that, it would be

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-76950955391764315422009-02-09T23:20:00.007+01:002009-02-16T00:11:06.117+01:00

Another video to show how Aileron differential is reduced when using butterfly mix such as it can be in a competition glider. Very useful to keep turning while airbrakes are fully out.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-37471776732158428852009-02-08T21:07:00.008+01:002009-02-10T22:09:34.162+01:00

Another interesting chip as a possible improvement of the Atmega168. Same pins, but more SRAM (2k) and more Flash(32k). It should fit in the Arduino easily.Nice evolution to the atmega168, but has some drawbacks:- the bootloader from Arduino do not work from scratch,- the tools avrdude, gcc-avr do not know the 328.[edit] correction: - the last version of Arduino (0013) supported the 328: It

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-78621641420994611222009-02-02T23:43:00.005+01:002009-02-03T23:40:20.358+01:00

Today I received a new toy :) Could be a good replacement for the XBee module, less expensive more flexible, approximately the same size than the Maxstream Xbee pro.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-29527776472164337212009-01-29T23:58:00.008+01:002009-03-05T09:25:26.842+01:00

Here is two short videos to demonstrate how stick input are mixed with RCHome. The first video show ailerons differential with two servos. Differential rate is approximately 40%. Servos moves in opposite direction: Next videos shows a snap flap mix, elevator to ailerons. When pulling the elevator, both ailerons servos moves in the same direction:

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-56661856684302701952009-01-27T13:16:00.002+01:002009-01-27T13:31:06.780+01:00

Now the main part of mixers/settings/tuning logic is coded, but not tested. All settings currently are changed in the PC, and then downloaded in the radio. This is the second version of the sofware. It should still fit in the Atmega168, provided not too many settings are configured. I tried to put as few as possible limitations in the software, to allow any number of mixing and tunings. The first

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-63783617487708644662009-01-13T12:52:00.007+01:002009-01-13T13:58:32.084+01:00

I had the opportunity to get in hands several types of RC transmitter. Most of them share a common approach to enter the model settings: they use menus which provide functions with sometimes obscure names like AFR, ATV, snapflap, differential,... lot of abbreviations which may be not also in your native language. As long as you understand what each function and its potential side effects is

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-25366178600973281892009-01-09T19:01:00.004+01:002009-01-09T19:09:47.306+01:00

Here are some 3D-view of the transmitter. Thanks to Laurent Lombardo.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-31950837382199336882008-12-24T00:45:00.003+01:002008-12-24T00:55:59.259+01:00

Finally I received the sticks. There are from a Futaba FC-18 transmitter. Their price is reasonable (approx 50€ each, dec 2008).Quality seems good. They are accurate et pretty smooth. Stick have 5k potentiometer, and trim have 10k potentiometer.Trims can easily be removed from the stick. They are just fix to the stick frame with two screw.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com2tag:blogger.com,1999:blog-9038373468397900666.post-81774559549420908082008-12-21T18:25:00.004+01:002008-12-21T18:51:26.296+01:00

Sorry for the bad quality, it is still a very early draft.I intend to make it as ergonomic as possible while keeping it simple. Both side are rounded to be confortable in hands, and below the low cover is embeded leaving some space for fingers.As you can see, there is no trim. The idea is to use "auto trim" as described by jef raskin who pioneered the human-computer interface at Apple (not less!)

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-64408915509881512182008-12-21T16:52:00.003+01:002008-12-21T18:25:52.358+01:00

After having play just a bit with the AVR32, I am not convinced. This chip looks young, there are not many people developping on it, it is still in an early phase for Atmel, can't found that many examples, it requires the use of an OS like freeRTOS, flashing under USB and linux is a boring, etc...To stay with simple 8 bits chips, I am thinking to use a multiprocessoir architecture, like mrdunk

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-37471129538800024442008-12-14T23:02:00.003+01:002008-12-14T23:46:39.937+01:00

I have started to play with the AVR32 chip on the board from alvidi. Well, it is not as easy as arduino board, or AVR 8 bits chips. First, there is no "pure" avr-gcc" available, but a gnu-toolchain version made by Atmel. As I am working under Linux, I used the Linux version. You can forget the simple "PORTB" or "DDRB" register names that are used on AVR8. Names are mostly different ahd hardly

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-25975897446141809932008-12-06T22:55:00.003+01:002008-12-06T22:58:40.783+01:00

Here are some screenshots of current screens:

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-58482367742523024842008-12-06T17:45:00.003+01:002008-12-06T17:54:56.291+01:00

Well, the Arduino SRAM start to be too small for this application (no surprise). I coded too many static objects in a first implementation, so it went out the 1kbyte of memory. After some new lines of code, it's much better. No more RAM problem. But now, Flash memory space is reducing a lot. There is only less than 5kb left and only few more features will be integrated. So few features

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-18076436084053551262008-12-02T00:28:00.001+01:002008-12-02T00:29:24.484+01:00

test video

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-49991517107350914412008-12-01T23:35:00.007+01:002008-12-02T00:17:15.936+01:00

The coding of menus and actions logic start to be consistent. But it takes more space in flash than I expected. It's now around 9KB and still 6kb left.This is a small video which shows the menus I just coded to set the servo neutral and maximum course. The values are kept upon reboot. Still one or two little bugs, but it works fine.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-54151291833315291012008-11-26T23:48:00.007+01:002008-11-27T00:09:54.409+01:00

Still progressing slowly on the software, and had some problems with the development toolchain Avr-gcc/g++ as it does not support the full c++ syntax, especially new/del/ and virtual functions.I spend some hours to write a first version in C-like, when someone from rcopensource list point me to this very interesting thread.So, with this help, I rewrote the state machine of the UI in C++ language

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-32140315306566756212008-11-23T22:31:00.004+01:002008-12-06T18:01:10.818+01:00

Intersting board with a microcontroller 32bits: Atmel AVR32 AT32UC3A1512. It has 512k flash, digital IO and 8 analog input, 4 UARTs, audio stream output, .... plenty of things and more.The datasheet.The board is called Alvidi and can be bought here: Avr32 Alvidi

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-50622195770105370952008-11-17T23:42:00.005+01:002008-11-17T23:52:12.928+01:00

While I am progressing on the software of the radio, I found it could be useful to add a feature to make the radio compatible with Microsoft:And I could have add on the screen (but there is not enough space): "please note in case you damage your plane, we deny any responsibility..." :)

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-47705912642791767432008-11-11T22:26:00.007+01:002008-11-11T22:48:35.315+01:00

Here are some pictures of the transmitter+LCD prototype. I reused an old LCD that I got from an old network equipment, so it is a bit ugly ;). The LCD is removable from the transmitter. The idea is to insert the LCD display in the transmitter for the setup of the plane. When the setup is complete, the LCD display can be removed, and go flying with just the transmitter and no lcd.There are 4

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-40240504361935131622008-11-09T12:21:00.002+01:002008-11-09T12:27:17.923+01:00

A new yahoo list has been created to discuss about an RC Open source.The list is in French, and has alredy many discussions:http://fr.groups.yahoo.com/group/rcopensourceIf you are interested to participate, please join.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-62230899562164318032008-11-09T12:05:00.005+01:002008-11-13T19:40:45.838+01:00

The well known site hackaday has kindly write a news about "effetdebord": http://hackaday.com/2008/11/07/arduino-rc-airplane/And same for Make Magazine:http://blog.makezine.com/archive/2008/11/arduino_powered_rc_airpla_2.htmlThe number of visits has exploded, this is great, thank you guys!

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-33843692460926101562008-11-01T22:00:00.012+01:002008-11-01T23:06:40.903+01:00

Here is the receiver I made as explained on the O24RCP web site. The site explains with many details how to make it, and provide related firmware image. The only tricky thing it to be careful with the components selected and the way to position them so that they fit under the XbeePro module. The picture below show the receiver without the Xbee:The image was flashed with the very simple ICSP

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-71015225414850123682008-10-24T23:13:00.003+02:002008-10-24T23:22:47.577+02:00

First attempts to use a lcd. It is connected with 8 wires for datas and 3 for controls. Connection with 4 wires could be another possibility. The soft library I used is a bit slow to display: there is too much temporisation between caracters. White on blue is not too bad, and led Backlight improve a lot the readability.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-14071238196873015782008-10-21T21:09:00.013+02:002008-10-21T22:33:32.071+02:00

The transmitter is based on a Arduino Diecemilla with an Xbee shield and an Xbee pro. Stick are connected to the Diecemilla though a small board. The +5V and the ground wires are directly soldered on the Arduino and distributed to each stick through the small board (red and blue wire on the picture).On the Shield, jumper must be set to PWR and XBEE.The large vertical board above the battery is

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-46195996955710856402008-10-15T22:52:00.009+02:002008-10-16T21:25:29.326+02:00

Premier vol de mon vieux Yak avec une Radio perso. :)Here is some video extracts of the first fly. Thanks to the Zhen who did take the video and pictures.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-49804662518166675142008-10-13T23:42:00.008+02:002008-10-14T22:04:39.514+02:00

After some fixes within the software, I am now getting closer to the first fly. I did some preliminary tests of servos and speed controller. All behaves good. The tail and rudder servos are bad quality and they move by small steps. But they behave the same than with a 12Z Futaba radio.Speed controller are ok, and motor on seems to behave correctly. We'll see what happens when the model will be

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-26524643360988992612008-10-05T23:50:00.007+02:002008-10-08T13:48:00.126+02:00

Here is a video showing the transmitter and receiver working. Transmission between transmitter and receiver is numeric. The receiver decode the servo position given in bytes and transform it in the right pulse and timing to move the servo.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-4650247992323135212008-10-05T23:40:00.004+02:002008-10-05T23:49:41.839+02:00

This is the prototype of the receiver. It is much too big and too heavy, but it's just a prototype. It's not easy to sold all this stuff. When mounting it, I made a mistake with the Wee board that I sold at the wrong position. I had to unsold it and to move it, it was quite a nightmare.

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-64162776918501823532008-09-30T23:13:00.006+02:002008-09-30T23:32:26.595+02:00

The transmitter is an old Graupner D14 box, with its sticks. All the original electronic has been removed. The prototype has 4 channels, but more could be added, up to 6 or 8. The case is even too big for this electronic. It has very simple programmation, as there is no possibility to change any setting in the transmitter, except by reprogramming the Arduino :) More possibility can be added later

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-23108713068754692932008-09-16T11:59:00.008+02:002008-09-16T12:38:17.600+02:00

This is my very first home made RC receiver. It works on 2.4Ghz band, and can control up to 6 servos. It receives datas from the transmitter for servo position, but can also transmit back informations. As it is home made, it requires a special transmitter to work with. It keeps servo positions even if there is no transmitter. Later on fail safe will be added.It is made with ready to use boards

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-53686313197149935152008-09-14T22:18:00.003+02:002008-09-14T22:48:32.210+02:00

Today, I have been able to control remotely servos from a PC through a pair of XBee modules. On the receiver part I used an Arduino Dicemilla + XBee module and Futaba servos. This makes quite a big receiver to put in an RC modele, eheh, but hopefully the size should be smaller later on.On the sender side, I used an Xbee Pro connected to the PC through the USB/serial cable. The PC sends commands

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com6tag:blogger.com,1999:blog-9038373468397900666.post-7495110824464476532008-09-14T21:48:00.003+02:002008-09-14T22:07:32.311+02:00

ok, given than more and more people connecting to this blog are english spoken, I switch my blog to English. Sorry for french :), if there is something you want to ask, do not hesitate to ask your question in comments or by mail in French.Yesterday I received my Wee from SParkfun. It's the same thing than an Arduino except that it is much smaller, has one or two analog entry less, and runs at

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-13922730096661243712008-09-11T22:29:00.006+02:002008-09-11T22:42:40.508+02:00

Le soft pilote maintenant jusqu'a 8 servos, avec une precision assez bonne. Les servos ne grognent pas et se deplacent en continu d'un coté a l'autre selon mon petit programme de test. J'ai utilisé les interruptions avec un algo a ma sauce pour respecter au mieux les timings. Cela fonctionne bien pour l'instant, j'ai testé avec des servos futaba et un graupner. Le pilotage des servos se fait a

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-2261736966385961562008-09-11T21:15:00.011+02:002008-09-11T22:48:55.229+02:00

Pour "debugger" les problemes de timing pour le pilotage des servos, un oscilloscope est quand meme bien pratique. Seulement voila, ca coute cher ces bestioles pour un usage tres limité. Ou alors il faut avoir un copain pas loin qui en a un a vous preter, mais pas toujours facile d'avoir l'engin sous la main au bon moment.La solution simple existe: utiliser le PC comme oscilloscope en entrant par

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-68789342654281331812008-09-04T23:53:00.007+02:002008-09-05T00:08:35.086+02:00

Les donnees sont envoyees par l'Arduino vers le XBee Pro a travers le port serie, puis le Xbee (Pro) envoie vers le second Xbee qui transmet alors vers le port serie du PC. Les connections series sont configurées a 9600 bps. Ca marche deja pas si mal!

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com3tag:blogger.com,1999:blog-9038373468397900666.post-60150742525499680612008-09-03T21:55:00.006+02:002008-09-04T00:29:37.410+02:00

Nouvel essai ce soir pour comprendre pourquoi les servos vibrent. En fait, le soft n'est pas le seul probleme. Il faut aussi une bonne alimentation des servos (evidemment) mais aussi un bon potentiometre. Le mien pas de tres bonne qualité oscille un peu et donc fait vibrer legerement le servo.Le soft aussi: une simple boucle avec delay fonctionne bien, alors que l'utilisation de librairie servo

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-22779548270466877932008-09-02T23:37:00.008+02:002008-09-03T21:54:57.962+02:00

Le plus simple pour programmer un Arduino est d'utiliser le soft Arduino. Il integre a la fois un editeur, un compilateur et le telechargement par le port usb/serie. Il y a du java quelque part, mais se base sur la toolchain gcc. Enfin c'est ce qu'ils disent dans la doc. L'avantage est qu'il existe pas mal de librairies qui simplifient beaucoup la tache, et permettre l'ecriture rapide de

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-79242355223874762312008-08-31T10:23:00.002+02:002008-08-31T10:25:03.312+02:00

Voila ce que j'ai recu la semaine derniere:

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-84575803679704675212008-08-27T21:40:00.006+02:002008-08-27T21:59:00.322+02:00

Finalement, je passe directement a l'etape "controle d'un servo par un potentiometre". Ca n'est pas tres compliqué, a condition de bien comprendre comment piloter un servo. Apres avoir essayé les differentes librairies Arduino ou Wire sans trop de succes (j'avoue ne pas avoir fait de test tres poussé pour comprendre ce qui ne marchait pas), j'ai finalement utilisé le code d'un autre blogger pour

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0tag:blogger.com,1999:blog-9038373468397900666.post-72188100542810810412008-08-23T22:12:00.011+02:002008-08-31T10:38:31.802+02:00

Et voila, j'ai enfin recu mon Sanguino. Enfin ca a ete assez rapide, a peine plus d'une semaine. Voila donc les composants recus: En suivant les instructions de la page http://sanguino.cc/1-0kitassembly c'est tres simple a monter, il faut moins de 2 heures. Mieux vaut avoir une panne de fer a souder fine, car certains trous sont a peine etamés sur le dessous.Voila ce que ca donne: Ensuite, vient

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-9740914812590907992008-08-18T21:39:00.010+02:002008-08-31T10:37:58.149+02:00

L'Arduino, vous connaissez ? C'est un petit microcontroller pratique pour de petites application electroniques. Il se programme facilement par un port USB en Gnu C avec un environnement de developpement totalement libre.Choisir le bon microcontroller n'est pas toujours simple, le choix est vaste. J'ai trouvé qur cette page quelques indications utiles: Choisir un microcontroller (anglais).L'atmel

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com1tag:blogger.com,1999:blog-9038373468397900666.post-6133238367840739842008-08-18T21:24:00.007+02:002008-08-31T10:13:21.185+02:00

Bienvenue sur mon blog.Vous pouvez aussi consulter mon site web consacré au modelisme et au F3F: http://obor.free.fr

Oborhttp://www.blogger.com/profile/03524068172931231702noreply@blogger.com0