Posted by Mad_angler1 | Jun 18, 2016 @ 04:56 PM | 7,903 Views
The YX YXC02 Multi charger for the DJI Phantom 4


The Phantom 4 is available from DJI http://click.dji.com/ewNB7_KlW2SdbyRy?pm=link&as=0003

Please Note: As with all my own blog post all links may be affiliate links and i will receive a small commission on any purchase bought through them , if you wish to support me then thank you however it is not expected .


The Charger





Design is similar to the Phantom 3 version with the spec listed on the top, Input 100-240v with secondary of 17.5V 12A total, Each output limited to 4A so it is lower than the 100w DJI adapter producing 5.7A but it will charge 3 x Phantom 4 packs at the same time and has the option of doing the controller as well but this is linked to one of the outputs so if used that pack will take longer to charge compared to the other two



...Continue Reading
Posted by grmis | Jun 18, 2016 @ 03:17 PM | 12,321 Views
Hi,

Here is a simple system to measure current, voltage, power and mAh. It is based on an Arduino, a (Hall effect) current sensor (Allegro ACS755-50 or ACS758-50), and an OLED display (using the SSD1306 driver).

This sensor can measure current up to 50 A, but it will not be destroyed if you exceed this value (the datasheet says 200A max.). I give an example of code below, but it is of course easy to customize for your needs (averaging, total energy, battery internal resistance...). One can also use a different sensor if you want to measure smaller currents with a higher precision.

If you find this useful, or if you have some question, do not hesitate to post a message here !

G.

Here is the Arduino code :
Code:
// ================================================
// Author: GRMIS on RCGROUPS
// [email protected]
// June 2016
// ================================================
// I2C OLED DISPLAY: SCL = A5  ,  SDA = A4
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET);
// ================================================
//Timing variables:
int now,previous_screen,previous_measure;

//Analog input connected to the current sensor
const int ACS755_pin=A0;
//Analog input connected to the voltage divider
const int volt_pin=A1;

//Button pin (to reset the min/max values)
const int Button1=2;

int Offset;
float current;
float voltage;
float
...Continue Reading
Posted by Thunder50BMG | Jun 18, 2016 @ 01:23 PM | 9,287 Views
Just another KK2.1 fun project to share.
The KK2 FC has been branded as a dirt cheap particular FC but,with it's capabilities ,it can give more fun compared to all those pricey fc's.The KK2 is designed for flying, from acro to project like this and if you are really up to it , custom mixes are like endless.

.....and this CO2X KK2.1 CHINOOK is born.

Here are some close-up pix and maiden video :

...Continue Reading
Posted by phil alvirez | Jun 18, 2016 @ 12:59 PM | 6,556 Views
Oscar Wilde said that "the only thing worse that not getting what you want, is getting it".
i never thought much about it because i thought it was 1 of his jokes.
that is, until today.
weather good, flew some of my new 2 meters sailplanes for calm for evaluation, and when the wind began to blow, i pulled 1 for windy weather, that has the vario that sends tones or tells the height.
tried to find a thermal but nothing. climbed 3 times to 200 meters (some 640 ft). the sky had just a few thin strips like veils. not the best conditions for thermals i know. the plane didnt sink, but no beeps.
i sure wanted thermals.
and then the vario began to sing. and up she went. up and up. 200 meters, 240, 300... then i began to worry. the plane looked smaller and smaller even if i did nothing. so i moved away, but no matter where, the vario kept telling higher. tried to trim it down. then dive. then the wings began to flutter. so dont put so much down. eventually began to drop. 300, 270, and so on. took over 10 minutes to land. by then i didnt want to fly anymore. i kept telling to myself: so you wanted thermals, didnt you? the flight was over 30 minutes.
so think carefully what you want: the gods of the air may be watching and decide to please you.
Posted by dmrcflyr2 | Jun 18, 2016 @ 11:38 AM | 5,524 Views
Well as promised I ran this engine and shot some videos of it. I had some difficulty initially getting it started and it was completely my fault and not the engines. I neglected to follow the instructions for the initial needle valve setting and opened it too much. This resulted in a flooded engine that would not start.

Once I cleared the flooded condition and set the needle properly it was quite uneventful after that. The engine starts easily, runs well, and has good transition from idle to WOT. I have the needles tweaked pretty well in the second video. I might be able to lean the low end a click or two more, but for the most part this engine is ready to drop into an airplane.

It runs just like my first one did in 1989, very strong. I took a few pictures inside the engine after my 4 runs as well. As you can see it still looks new.

ASP 46A the first run (10 min 30 sec)


The performance run.
ASP 46A Performance run (4 min 34 sec)
...Continue Reading
Posted by fullchain | Jun 18, 2016 @ 11:14 AM | 2,295 Views
Unexpected breakages, any multicopter-flyer's true constant.

Even though you might not understand everything I say, I think we all know these frustrations very well. As well as the eventual gratitude anyway in the end that I am even privileged to be able to fly.

Not a one of us had a clear camera that day. It was either one of our boardcams, recording cams or both lol.

Ah, the life of a student... of life...


QCQC Vlog001 - Melancholy Morning (4 min 7 sec)

Posted by Luke P | Jun 18, 2016 @ 09:52 AM | 2,455 Views
Hello people of rc groups.

After getting a little frustrated at both a lack of reviews for some products, and the quality of some reviewing channels i have decided to take the matters into my own hands (and have some fun while doing so)

As a brief overview, My name's Luke, I bought my first RC plane when i was roughly 7.
it was a piece of junk air hoggs 2ch but it worked okish, didnt kill it till i was 17. now i have finally moved onto things like a scratch built 250 FPV quad as well as a franken built vtail. my latest plan to make a real big hotwire wing once year 12 is over.
I'm into anything RC but mainly stuff that flies.

Starting late august this year is the new youtube channel 'AusRC' it will feature a range of video styles including but not limited to; Reviews, FPV freestyle, Tutorials, Aerial footage and of course plenty of crashes.

currently no videos are being posted as i am still waiting on some special parts which will be perfect parts for kicking off the channel.

Subscribe to: https://www.youtube.com/channel/UC_v...irN2N5A0C8qVBQ and stay tuned for more info in a couple months.

AusRC - Coming soon! (0 min 45 sec)


Hope to hear from and get to know you all
-AusRC
Posted by kc8qpu | Jun 18, 2016 @ 09:10 AM | 4,388 Views
Tim and myself left Friday afternoon and drove 7 hours north to Harrisonburg VA. We stayed with some of Tims wonderful friends for the weekend. After arriving Friday around 730pm we spent some time with friends and settled in for the night.

We both woke around 7am or so. Had batteries charged and ready to go. After an awesome home cooked breakfast we were on our way to the field about 815. It would take about 20 minutes to get there. We found the club and started down the drive way and to our surprise, had to actually cross through a creek that was about 8" deep. This was a first for both of us going to any flying event. Ha. After Tim navigated the dangerous rapids, we decided to settle in on the end of the flight line.

Before unpacking we walked down the flight line catching up with friends and registering. Of course everyone was there. Including Gene Hood, who is Tims main competition.

The field faces east so we were looking right into the sun. I81 was also in that direction only about 500 yards out. To the right end was a tree line. It was tight. They decided to let the FAI guys fly first. It wasn't until about 1100 or so before our first round. We would fly two rounds in a row. One on flight line A and one on flight line B. Tim was not able to call for me on round 1, however Archie Stafford stepped up and helped me out. When I landed he gave me some great advice. On my down wind maneuvers I was using the same amount of...Continue Reading
Posted by The_RC_noob_bob | Jun 18, 2016 @ 05:04 AM | 2,294 Views
Hello,
I was making some batteries in serie 3 2S batteries.
Than I tried to hit the maximum speed.
Every time I was at a speed it stopped for 1s and than I could drive further.
And after the fourth time I tried I heard a knack, I think that it was a short circuit. My esc id dead. But my motor idk? Is there a way to repair it?
I think to replace my esc with xerun RX8 but do I need to change my motor and I don't know if its dead.
Thanks for help.
Posted by toy | Jun 18, 2016 @ 04:56 AM | 5,128 Views
Vortex 285 race quad VS Bolt 250 with Tattu 4s lipo battery and Thank you for Mad - Almog

Vortex 285 race quad - tattu 4s 1550 45c Lumenier 1806 2300kv Dal 5040

Bolt 250 -Tattu 4s 1300mah lipo 75c Cobra 2204 2300kv Dal v1 5045 bullnose Esc rg20

Welcome to Rate..Comment..Subscribe...Spread the word. I know you guys like sharing my stuff.
Vortex 285 race quad VS Bolt 250 with Tattu 4s lipo battery (1 min 22 sec)

Posted by Tecesy | Jun 18, 2016 @ 04:13 AM | 4,166 Views
off-road rc car
Posted by Lycan Animal | Jun 18, 2016 @ 04:06 AM | 37,925 Views
Original: 1920 X 1080 Pixels 30 Frames/Second Bitrate 14415 kbps
Audio: 129 Kbps mono 8kHz

Syma X8HG - Raw Footage 1080 HD (5 min 1 sec)

Posted by Ramy RC | Jun 18, 2016 @ 03:12 AM | 15,614 Views
Hello everyone

I am building the x wing from star wars and its almost finished but am not sure about the CG , I used the CG calculator and it says around 4cm ! but i am not sure if that's right ,

any ideas ?

thanks.
Posted by Jack Crossfire | Jun 17, 2016 @ 11:32 PM | 4,233 Views
Finally found the hackaday nugget about anti cogging algorithms.

http://hackaday.com/2016/02/23/anti-...shless-motors/

Not sure why it was written in the form of a research paper with grants, long after Chinese perfected anticogging in their gimbals. At least, it is very math intensive & if it wasn't published, it would have remaned a Chinese secret forever.

A simple algorithm tabulating phase offsets for each angle did indeed make the motor slightly smoother but not perfect. The hall effect sensor was key to developing the anticogging table. It became clear that anticogging was still a science project, not useful in commercial products. Another key was the motor doesn't have any cogging with no current.

Also, any anti cogging based on the current sensors isn't useful because any closed loop is too slow. The needle pointed back to the electronics rather than the motor being the problem.

At least, it made a graph of phase offset vs angle.
Posted by KCreep | Jun 17, 2016 @ 10:43 PM | 4,872 Views
Got two new quads in the mail today, one tiny and one big. The WLToys Q343 is particularly interesting since it uses a smartphone for control and it transmits live video on the phone as well. It even has altitude hold! I'm curious to see how well the smartphone control, barometer and camera works in practice in such a tiny little thing.

The Syma X8HG is a 350 sized quad with a 1080p GoPro style camera. The candy apple red strikes a nice contrast with the silver stickers and from my experience with the X5HW, it's little brother, it'll fly just as nicely but with a much better camera.

Both reviews of these will be out soon, right now I'm working out on it.
Posted by xmlnoob | Jun 17, 2016 @ 10:24 PM | 3,013 Views
K123 AS350 Ecureuil .

Look nice, fly nice! Except the heat problem, it 's darn HOT!
Posted by ant0 | Jun 17, 2016 @ 10:15 PM | 6,395 Views
Can a good RM1 airfoil be designed? Yes, it can. According to the xflr5 analysis smoothed RM1 (RM1sm) can perform suspiciously well.

Below are the two RM1sm airfoils that I came up with that are quite close to the PW51 airfoil at Reynolds numbers in the 50000-150000 range. Notice the conventional rounded/smooth leading section and the flat sections aft of it.