• Male
  • Tokyo
  • Japan

Randy's Friends

  • tri tran
  • Pavlo Molchanov
  • JerryCheung
  • Iccobella Cheung
  • Flycam
  • Eric Zhu
  • dronebohne
  • Jacek Szostak
  • Juan Manuel Uteda
  • Alpha
  • mk
  • Gokmen Inik
  • befinitiv
  • Enzo Buono
  • KB

Randy's Groups

Randy's Discussions

Copter reliability vs functionality

Started this discussion. Last reply by Marco Robustini Jun 19. 204 Replies

Copter-3.3 beta testing

Started this discussion. Last reply by Randy 2 hours ago. 3366 Replies

ArduCopter-3.2.1 Beta Testing

Started this discussion. Last reply by Johann Bruwer Jul 22. 585 Replies


Welcome, Randy!

Latest Activity

Randy replied to Randy's discussion Copter-3.3 beta testing
"IvanR, Thanks for the report.  That really does look pretty terrible with the vehicle oscillating quickly in roll and pitch at a couple of times in the flight.  I suspect reducing the WPNAV_ACCEL to 100 will help but it's current…"
2 hours ago
Gleb Falaleev replied to Randy's discussion Copter-3.3 beta testing
"Good advice! "
2 hours ago

Randy replied to VENKATAKRISHNAN M's discussion APM COPTER NOT PROCEEDING TO 2ND WAYPOINT in the group ArduCopter User Group
"I've seen this reported a few times and it's almost always ended up being that the WPNAV_SPEED was somehow set to zero."
3 hours ago

Randy replied to Bim's discussion Indoor navigation with ArduCopter in the group ArduCopter User Group
"Bim, There are three possible solutions I think: 1. implement a angular controller in Guided mode to allow the companion computer to more directly control the vehicle's lean angles.  The companion computer would be responsible for…"
3 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"Josh, The GPS driver starts at 38400 but it does try various baud rates if it doesn't find a GPS.  I've never tried it myself to be sure but Tridge and Michael DuBreuil who know more about the GPS driver tell me this."
3 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"Michael, Could you try testing with the latest Tower beta app?  There's a new version out today and I just gave it a try and it seemed ok. By the way this latest Tower beta also includes the live EKF viewer (Vibe viewer will come in about…"
3 hours ago
Josh Welsh replied to Randy's discussion Copter-3.3 beta testing
"Hey Randy, I thought on boot, the autopilot was setting the gps's baud rate back to 38400, regardless of what was already set via uCenter.  Is that not accurate? I'm very likely mistaken, but don't know how to read the code…"
4 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"I've updated the image here and added a new section here. "
4 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"So, yes, this "Calibrate Level" button on the MP is (indirectly) adjusting the AHRS_TRIM_X and AHRS_TRIM_Y parameters.  This is a good way to adjust the trim without having to do the whole accel calibration again.  As many have…"
5 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"Paul, Yes, totally agree that disabling the 2nd GPS is not the ideal solution.  It's on the to-do list to fix for AC3.4 so I'm sure we will sort it out in the coming months."
5 hours ago
Paul Atkin replied to Randy's discussion Copter-3.3 beta testing
"Randy, Thanks for this information, i will try to experiment with ucenter. As of disabling second GPS it is not a real solution and i still believe firmly proper design requires full redundancy of all critical navigational systems and current code…"
6 hours ago

Randy replied to Randy's discussion Copter-3.3 beta testing
"Paul, I just reviewed the commits and as far as I can see we haven't made any changes to the GPS code between -rc9 and -rc10.  Just in case anyone wants to check (now or for future reference) the list of commits can be seen here and…"
6 hours ago
Phill Simpson replied to Randy's discussion Copter-3.3 beta testing
"K Index indicates all is quiet "
11 hours ago
Paul Atkin replied to Randy's discussion Copter-3.3 beta testing
"Unless Randy sees something else in the log i sent i think issue is with code switching between 2 gps signals non stop and making drones final position unstable."
12 hours ago
Wes replied to Randy's discussion Copter-3.3 beta testing
"GPS quality out on the west coast has been very unreliable over the last week. Some times I get 15 sats in 30 seconds other days this week no lock after 30 minutes. All this with no change in firmware. Others on RCgroups have given similar…"
12 hours ago

Nathaniel Caner replied to Randy's discussion Copter-3.3 beta testing
"Stephan, Glad you are happy with 3.2.1! Do you know or appreciate why you are so happy with 3.2.1? It's because of this exhaustive process of beta testing. Lets refresh our memories. Work on 3.2 beta began with the first release candidate on…"
12 hours ago

Profile Information

About Me:
Lead developer of ArduCopter. I coordinate releases, provide support for users having trouble with their copters, add new features (most often based on ideas and suggestions from the community). I also help others get their code integrated into ArduCopter.

You can find numerous video tutorials from me here:
Please tell us a bit about your UAV interest
Interested in quads and helis mostly. I got my start in this field by reading the electronics tutorials from Sparkfun and from watching the success of Jack Crossfire's vicacopter. I've learned an enormous amount from the combined wisdom of the people on the DIYDrones forums and members of the core dev team including Jason Short, Tridge, Doug Weibel, Leonard and many more.
Karuizawa, Japan

Randy's Photos

  • Add Photos
  • View All

Randy's Blog

NAVIO+ Linux board with APM:Copter 3.3

Posted on June 3, 2015 at 12:00am 23 Comments

Click here to skip the commentary and just see the vehicle flying.

The video above shows my first attempt (which was successful) to fly APM:Copter using a Linux board (…


Multi-Vehicle testing with APM:Copter, Tracker and Mission Planner

Posted on May 3, 2015 at 8:21pm 33 Comments

For some tasks (like Search and Rescue and mapping) what you can do with one vehicle, you can probably do faster with multiple vehicles.  To test how well it works in practice I tested…


ArduCopter 3.2.1 released

Posted on February 11, 2015 at 1:00am 83 Comments

Warning: there was a period of about 12 hours after this blog was first posted where an older version (AC3.1.2) replaced AC3.2.1 for APM2.  If you think you may have downloaded for the APM2 during these initial period, please check the version on your board by looking at the title bar of the Mission Planner (see…


Steps towards S&R in Japan

Posted on December 22, 2014 at 6:30pm 8 Comments

We seem to have a lot of natural disasters here in Japan (eruptions, mud slides, earthquakes) and like everywhere else we are counting on UAVs to…


ArduCopter 3.2 Released

Posted on November 24, 2014 at 8:56pm 242 Comments

ArduCopter 3.2 (aka APM:Copter) has been released as the default version replacing AC3.1.5. This is the exact same version that we invited all users to test two weeks ago.  Users who wish continue using AC3.1.5 can find it under the "Pick…


Comment Wall (28 comments)

At 8:44am on January 5, 2011, Jack said…


I have been working on my own Quad with the NG code and have setup the Sonar and have it working very well . I have an indoor version with sonar and IR sensors and would like to know were the IR sensors are conected, what pins. I see you were working on implementing this so If you could help with basic setup I can try my hand at testing. Thanks for your work on the Sonar and good luck on the obstical avoidence.


At 5:47am on January 30, 2011, Kári Davíðsson said…

Thanks Randy. 

I do not have write access to the svn repository.

So I will send you the changed AP_ADC lib probably later today.

I am not sure if a circular buffer is needed. The beauty of a 1st order IIR filter is that we only need one "old" sample and if a second order is needed only two old samples. But I will look a little better into the filter selection before committing anything to you.

At 5:45am on August 24, 2011, Jiro Hattori said…

Hi Randy

 One of the way to introduce technology of arduino as IMU is that something like what you have done. Most of the Japanese model flyer love to fly traditional helicopter. 

 Another approach may be exhibit something very unique at MAKE fair at Tokyo Institute of Technology.  There will be many open source hardware and software freaks as well.

At 9:10pm on March 7, 2012, Ravi said…

hi randy, i had been following your forum for align450. i just got my APM2 purple. i loaded the ardu heli firmware. everythings looks to be ok on mission planner. but there is no PWM on servo out pins. i armed the APM2 and does gets armed. the radio callibration bars move proportionately. evrything seems to be OK. but in 'status' there is no PWM on channel out pins. it shows '0' PWM on all out channels. can uou please suggets what might be the reason. the APM2 works fine with arduplane and arduquad firmware. ravi

At 5:53am on March 16, 2012,


I had a different problem with my APM2 that I was able to solve by following the procedure found in the wiki with a search for APM board problems.  My board would not connect to the planner and it works now.

Good luck


At 2:18pm on May 15, 2012, wilson javier madrid sossa said…

hello hello hug.
I can help with anything, I did several plannings flight with tri and firmware 2.0.49 and flew very well.
I did a quad and install 2.5.4 program a waypoint flight and the team took off like crazy.WP PIDs are by default and does not really move as you do. can you give me some information.

I appreciate your help

At 4:41pm on May 16, 2012, wilson javier madrid sossa said…

Please can you help me. I was flying my quadcopter and hold position when you turn the team went to ground. these are the last two log. I appreciateprompt help.


At 3:54pm on September 29, 2012, Marooned said…

Hi Randy

After your changes to Optical Flow I'm having troubles with compiling the sources:

ArduCopter.cpp: In function 'void init_ardupilot()':
ArduCopter.pde:-1: error: 'SPI3' was not declared in this scope
ArduCopter.pde:-1: error: 'SPI3_SPEED_2MHZ' was not declared in this scope

I have spi3.h file include in ArduCopter.pde but somehow it's not working that way. I did fetch&rebase with original repo.

At 3:12pm on September 30, 2012, Marooned said…

Sorry for troubles. It's working now. Looks like Arduino IDE had some hiccup.

I should probably move to some better IDE as I'm using Arduino only for compiling/uploading and all files are edited in my fav editor and I have to restart Arduino every time I change something as it doesn't follow outside files changes.

Anyway, sorry for bothering you.

At 6:30pm on December 1, 2012,
William Premerlani

Hi Randy,

Regarding a question that Shyam asked about gimbal lock when he was trying to use APM to stabilize a camera, he and I finally solved the issue. Here is a link.

No one on diydrones was able to help Shyam, he finally contacted me directly.

Best regards,

Bill Premerlani

You need to be a member of DIY Drones to add comments!

Join DIY Drones


DIY Drones Monthly


Season Two of the Trust Time Trial (T3) Contest 
A list of all T3 contests is here. The current round, the Pylon Race, is here

© 2015   Created by Chris Anderson.

Badges  |  Report an Issue  |  Terms of Service