Alexandre Mainardi (Nuvem UAV)'s Posts (9)

Sort by


The ArduPilot development team is delighted to announce a new stable release of plane, version 3.9.0.

For those of you who have been testing the 3.9.0beta releases then you won’t see any surprises here. That are no changes since 3.9.0beta6. Also, many thanks for testing the betas!

For those of you coming from the last stable 3.8.5 release there are a lot of changes. For a start, this is the first release to support both the ChibiOS RTOS on STM32 boards and the NuttX RTOS. Previously stable releases only used the NuttX RTOS. The ArduPilot project is moving to
ChibiOS for future releases, and we expect to drop support for the NuttX builds for the next major stable release (which will probably be called 3.10.0).

When you install the 3.9.0 release on board such as a Pixhawk1, Cube or Pixracer you have a choice of which build to use. Choosing ChibiOS will give you better performance and some very nice new features. Choosing the NuttX (also known as “PX4” builds) will get you the same base that we have been using for years.

There are a few features that are in the NuttX build but not yet in the ChibiOS build, in particular the ChibiOS build does not yet support PWM based rangefinders. That will be fixed in a future release.

This release has a lot of new features. Some of the most important ones are:

  • DShot support for controlling ESCs
  • BLHeli pass-thru support for ESC configuration
  • automatic compass orientation on calibrating compasses
  • improved VTOL flight code, with improved transition support and loiter
  • support for Devo telemetry output
  • new battery monitoring system, with more flexible failsafes
  • built-in OSD support for boards with a MAX7456 OSD device

In addition, this release supports a lot of new flight boards, including:

  • AirbotF4
  • F4BY
  • KakuteF4
  • KakuteF7
  • MatekF405
  • MatekF405-Wing
  • mindpx-v2
  • mini-pix
  • Omnibusf4pro
  • Omnibusf7V2
  • Pixhawk4 and Pixhawk4-mini
  • CUAVv5
  • revo and revo-mini
  • sparky2

We also now have custom ChibiOS based builds for some existing boards, including:

  • CubeBlack
  • mRoX21
  • Pixhawk1
  • Pixracer

This means you now have a lot more choice in selecting a flight board to use with ArduPilot.

This release was made possible thanks to contributions from dozens of volunteer developers in the dev team. In total there are over 5 thousand changes since the 3.8.5 release. Special thanks to:

  • Siddharth Purohit
  • Tom Pittenger
  • Randy Mackay
  • Michael du Breuil
  • Peter Barker
  • Mark Whitehorn
  • Paul Riseborough
  • Francisco Ferreira
  • Jonathan Challinger
  • Leonard Hall
  • Alexander Malishev
  • Nathan E
  • Marco Robustini
  • Luis Vale Gonçalves
  • night-ghost
  • Patrick José Pereira
  • Lucas De Marchi
  • Eugene Shamaev
  • Philip Rowse
  • Amilcar Lucas
  • Kelly Foster
  • Fnoop
  • Pierre Kancir
  • Stephen Dade
  • Jaime Machuca
  • vierfuffzig
  • Henry Wwurzburg
  • Malcolm Churn
  • Holger Steinhaus

We hope you enjoy flying this release as much as we enjoyed making it.
Happy flying!

Big thanks to Tridge and Ardupilot development team! 

Font and original discuss at ->

Read more…
We derive thrust, roll, and pitch authority from a single propeller and single motor through an underactuated mechanism embedded in the rotor itself.
This allows new types of conventionally-capable micro air vehicles which only require two motors for practical control. This contrasts with the many servos and linkages of conventional helicopters or the many drive motors found in quadrotors.
Conventional UAV formats applied to smaller and smaller micro air vehicles lead to significant design challenges. A swashplate-controlled coaxial helicopter must find room in its mass, size, and cost budget for four actuators (two big rotor motors, two swashplate servo motors) and a complex linkage assembly. A quadrotor must similarly support four motors and face the practical problems of rapidly shrinking rotors. Our new rotor system provides significant system simplifications while retaining all the advantages of cyclic control.
The main motor directly drives the propeller hub, which is itself connected to the propeller blades by two inclined hinges. The hinge geometry couples blade lead-and-lag oscillations to a change in blade pitch. Instead of only driving the motor with a steady torque, we add a sinusoidal component in phase with the rotation of the rotor to induce a cyclic pitch variation. The amplitude and phase of this control signal determines the magnitude and direction of the vehicle response.
This paper presents a new concept a MAV propulsion system capable of using a minimum number of actuators in dual rolls. This simplifies and lowers the cost of MAVs. Removing complex swash plates and reducing the number of actuators reduces the number of parts, thus increases reliability (fewer parts to fail), reduces maintenance costs, reduces vehicle mass, and reduces manufacturing costs. Experimental results for the actuator response are presented along with a demonstration of a full flight vehicle using this system for both active stability and maneuvering.
We have shown that a hinged, underactuated rotor can mimic the behavior of traditional cyclic control systems in small MAVs without requiring either additional servomotor actuators or complex linkage systems. Both the magnitude and response time of the resulting control moments are sufficient for stabilizing and maneuvering a small, 358 g coaxial MAV.
In future work, we wish to develop a technique for determining optimal geometric design parameters for power-efficient operation given application constraints on required moments, thrust, and rotor size. This will allow us to evaluate the system-level power efficiency of this technology verses other control strategies while taking into account the associated actuator and structure material weights. The ultimate aim of this technology is to achieve reductions in system complexity and actuator count that may enable future small, simple, and low cost micro air vehicles.

J. Paulos and M. Yim, “An underactuated propeller for attitude control in micro air vehicles,” in Intelligent robots and systems (iros), 2013 ieee/rsj international conference on, Tokyo, Japan, 2013.
Read more…

Plane 3.8.0 released

The ArduPilot development team is very proud to announce the release of APM:Plane 3.8.0. This is a major release, with a lot of new features and improvements. The release has been a long time coming, and the dev team would like to thank everyone who has contributed, in terms of code and documentation as well as the many testers of beta versions of the code.

To help with migration from the 3.7.1 release to 3.8.0 there is a migration guide here:

All users should read the migration guide carefully. While the firmware will try to auto-migrate most settings, please do very careful ground tests before your first flight with 3.8.

In total there have been over 4 thousand changes in the ArduPilot git tree since the 3.7.1 release, with over four hundred of those specific to fixed wing aircraft. Listing all of them in these release notes is not practical, but the following list will give some of the larger

  • addition of EKF3 support (disabled by default)
  • new SERVO parameter system for servo output configuration
  • support for MS5525 airspeed sensor
  • support for a wide range of tiltrotor quadplanes
  • support for tailsitter aircraft (including vectored tailsitters)
  • support for twin-motor aircraft, with differential thrust
  • new system for elevon, vtail, flaperon and differential spoiler setup
  • support for deep stall landings
  • support for dual-gps blending
  • support for masking compass types for driver loading
  • completely new DMA based and high sample rate IMU drivers
  • support for px4pro board from Drotek
  • several new compass drivers, new IMU drivers and new GPS drivers
  • new MANUAL_RCMASK system for fine-grained MANUAL flight setup
  • support for log rotation on disarm
  • numerous quadplane improvements
  • fixed loiter behaviour with Q_GUIDED_MODE=1
  • allow rudder arming in CRUISE and FBWB modes
  • fixed bug in transmitter tuning support
  • fixed bug in attitude integrator zero on mode change
  • added SYSID_ENFORCE parameter
  • fixed support for vtail rudder-only planes
  • greatly improved automatic landing accuracy
  • support for high update rates on all servos with SERVO_RATE parameter
  • greatly improved UAVCAN support, with parameters now in CAN_ parameter space
  • support for prop-hang on 3D aircraft
  • improved quadplane PID logging
  • smoother takeoffs for quadplanes
  • logging of side-slip and angle-of-attack estimates
  • added AETR, pre-mixer logging
  • automatic thermalling support

The documentation23 has had a major update as well, with new setup guides33 for popular aircraft types, including 4-channel planes, elevon planes, vtail and flaperon setups, tailsitters, quadplanes and tilt-rotors.

Many thanks to everyone who contributed to this release - it has been a long time coming, but I think it was worth the wait. The dev team hopes you enjoy flying it as much as we have enjoyed working on it!

Happy flying!

Thanks Tridge and ArduPilot development team!


Read more…

The THOR prototype can transition from hover to fixed-wing cruise mode by rotating its wings into ...

The THOR prototype can transition from hover to fixed-wing cruise mode by rotating its wings into alignment

Conventional multicopter drones are excellent at hovering and VTOL, but they can't cover long distances as efficiently as fixed-wing aircraft. A team of students from the Singapore University of Technology and Design is trying to get the best of both worlds with the Transformable HOvering Rotorcraft (THOR). 

THOR is just a prototype at the moment, but it has plenty of potential in industrial applications The Singapore University of Technology and Design is trying to improve on classic monocopter and hybrid UAV design with its THOR A look at the way THOR transforms from hover to fixed-wing mode A breakdown of the components in the THOR prototype

According to the design team, the THOR is based on a concept raised in 1913. Called the monocopter, it was "structurally efficient" – the whole frame is used to generate lift – but "strategically inefficient." The lack of counter-rotational systems meant the pilot and cargo would have needed to spin with the rest of the aircraft, making it impractical to actually ride in.

The Singapore University of Technology and Design (SUTD) isn't alone in trying to revive the monocopter. Lockheed Martinand MIT have both created monocopter-style concepts that have their roots in nature and were designed to explore how the idea could improve current UAVs. 


According to the team, the design of THOR improves on the basic monocopter design in a few new ways. The first involved a second wing – and yes, that means it isn't a monocopter anymore. Lockheed Martin's design only used one wing, but the SUTD team have fitted two wings that protrude from the center of the UAV. 

STUD took inspiration from the samara seed, a flying tree seed that can be carried long distances by the wind because of its inherently stable, wing-style shape. Although some variations of the seed look like a single wing (or propellor blade), there are other "two-winged" examples as well. 

The THOR's opposing wings are mounted at right angles to each other and rotate into alignment when making the transition from helicopter-style hover to fixed-wing-style cruising. The students have also created a passive system to shuffle weight around based on flight mode. When the craft switches from hovering vehicle to fixed-wing aircraft, or vice versa, the centrifugal force involved in the switch is used to move the ballast into a position to keep the aircraft balanced. 


It's just a prototype at the moment, but the THOR concept could be useful in a huge range of industrial environments. Agriculture, surveillance and payload delivery are three areas mentioned by the SUTD team, who say that most hybrid UAVs are only efficient in one of their flight modes. 

There are still a few tweaks that need to be made before the project is ready for public consumption. To make sure it doesn't just drop from the sky if there's a problem, the team is working on an autorotation system that will allow it to glide down safely without power. 

The THOR prototype can be seen hovering and transitioning to cruise mode and back again in the video below.

Source: Singapore University of Technology and Design

Read more…


Not satisfied with the specs of off-the-shelf brushless DC motors? Looking to up the difficulty level on your next quadcopter build? Or perhaps you just define “DIY” as rigorously as possible? If any of those are true, you might want to check out this hand-wound, 3D-printed brushless DC motor.

There might be another reason behind [Christoph Laimer]’s build — moar power! The BLDC he created looks more like a ceiling fan motor than something you’d see on a quad, and clocks in at a respectable 600 watts and 80% efficiency. The motor uses 3D-printed parts for the rotor, stator, and stator mount. The rotor is printed from PETG, while the stator uses magnetic PLA to increase the flux and handle the heat better. Neodymium magnets are slipped into slots in the rotor in a Halbach arrangement to increase the magnetic field inside the rotor. Balancing the weights and strengths of the magnets and winding the stator seem like tedious jobs, but [Cristoph] provides detailed instructions that should see you through these processes. The videos below shows an impressive test of the motor. Even limited to 8,000 rpm from its theoretical 15k max, it’s a bit scary.

(Dan Maloney -


But, How it works? 

This is the Halbach array setup. Every 5 magnets the pattern repeats. for more information.

Here is the explanation / assembly video

Alexandre Mainardi

Read more…


"The drone market today can be described as a melting pot of different technologies, where combinations of hard- and software components and service features are provided to the end user. In order to create sustainable success in this extremely fast moving market it is essential to maintain strategic partnerships or invest in a solid UAV portfolio. This is nothing new and as we showed in our recent publication this is a process that started quite a while ago, long before anyone thought about drones to be the next big thing.

However, lately a few players have been extremely busy with engaging in new partnerships, looking for investment opportunities and acquisitions.

Currently, the commercial UAV market consists of three dominant players, namely DJIParrot SA and the Intel Corporation.

Parrot started creating professional solutions at a very early stage. The acquisition of Software manufacturer Pix4D (2012) and MicaSense (2014) were great strategic moves and paved the way to highly advanced end-to-end solutions. Although profit margins in the commercial UAV market were very small at this time, Parrot did invest heavily into their new strategy. Building a new market segment has never been easy (or cheap) and the low-cost competitors from Asia also apply a lot of pressure causing market deficits especially in the hobby/prosumer sector. Despite, the share of the drone sector within the Parrot Group increased from 38% (Q1 2016) to 54% (Q2 2016) due to this strategic move.

Whereas Parrot started three years earlier, Intel Capital started in 2014 to invest into the drone industry. Now, Intel Corp. chooses a pro-active approach and moves into the market by acquiring the missing pieces of the puzzle around their high-performance chip-sets. The Intel RealSense platform combines hardware and software in a way that enables cameras to process and understand images, and eventually providing “computer vision” to flying drones. Before acquiring the German drone manufacturer Ascending Technologies earlier this year, the two companies had already engaged in a close partnership to improve UAV sense and avoid systems. Intel’s biggest and certainly most game-changing move was the acquisition of the mobile vision processor company Movidius. This acquisition paves Intel’s way towards autonomous systems – not only for unmanned aerial vehicles.

Other chip manufacturers such as Qualcomm and Nvidia have recently copied Intel’s strategy, as they see the immense opportunities in becoming technology suppliers for the emerging drone industry.

The third key player and dominant market leader DJI also started a number of new partnerships this year. While Intel and Parrot grew their drone business through acquisitions, DJI now uses partners to expand their business portfolio (e.g. the infrared camera maker FLIR, surveying expert Leica Geosystems and micro ADS-B transponder manufacturer uAviniox). For their position this strategy makes a lot of sense since DJI has everything it needs to bring drones up in the air and as such, does not have to acquire the technology. Partnering can be an extremely quick way to grow a company, particularly in times of rapid change. Without implementing difficult and time-consuming internal changes DJI can expand the knowledge of different industry sectors, boost innovation and increase their market share.

Initially partnerships were heavy on hardware but the demand to deliver high-quality end-to-end products more quickly and at lower costs has become a fundamental part of the entire UAV industry."

Read more…


Thanks to 12 air quality monitoring stations in Central London, the Plume Air Report lets Londoners track average pollution levels in their city. But do you know what you breathe in your borough? From street to street? Wherever you go?

Today, in London, we are launching the first ever flock of pollution-monitoring pigeons to map pollution in the city. We’ve partnered with global marketing & technology agency DigitasLBi and Twitter UK to equip pigeons of little backpacks carrying our ultra-light pollution sensing technologies, to track air quality all around London.

BANDEAU-07 small

The Pigeon Air Patrol will monitor air quality in the capital and report back via Twitter. In London right now?

>> Try tweeting your area to @PigeonAir <<

… and receive instant air pollution level from one of our lovely pigeons (named Coco, Julius and Norbert)!

You can also visit the campaign microsite, where you’ll see a live map of the pigeons’ flights, learn about air pollution and its health risks, find out more about the pigeons and download the Plume Air mobile app.

Our CEO, Romain Lacombe, says: “Air pollution is a huge environmental health issue, killing 10,000 people every year in London alone. Putting air sensors on the back of pigeons goes beyond raising awareness of this problem and helps Londoners understand the impact of pollution in an accessible, tangible and immediate way”.

Plume Labs BLOG)

Read more…

[IEEE CSS Video Clip Contest 2015 Submission]
This is a video introduction to controlling self-driving cars, specifically using PID-control. Special emphasis is placed on how the proportional, integral, and derivative gains affect the performance of the vehicle.

Music: - Solar Flares

Video References:

DARPA Urban Challenge MIT footage
Google Earth
Dog Driving Car
Car in Parking Lot

Script & Narration: Luke Johnson
Hardware & Control: Brett Lopez
Visualization: Shih-Yuan Liu
Editing & Overlays: Justin Miller

Lab footage courtesy of:
Aerospace Controls Laboratory @MIT
Jonathan P. How, Director

Thanks MIT Team!


Alexandre Mainardi

Read more…

Hello DIY Friend's,

This is my latest video, QAV250 Carbon Fiber Edition, Building TimeLapse Log, i hope you enjoy! 

Here is my Setup

Lumenier QAV250 Carbon Fiber Edition
OpenPilot CC3D Atom
Tiger Motor 12A 600hz simonK ESCs 
Lumenier (Tiger motor Rebranded) FX2006-13 2000kv motors
Gemfan 5x3 props
Lumenier CS-600 super camera
IBCrazy 5.8ghz cloverleaf ULTRA antenna 
Lumenier 1300mah 3s lipo
Mobius action cam 1080 30fps
Spektrum DX8

P .00215 .00245 .00610
I .00400 .00505 .00520
D .000040 .000040 .000020

And 35% Expo un my TX

I made this quad just for speed Racers, so maybe i'll add some more 4S emotion in the future... Any advices to increase my speed and stability are welcome!

Thanks for watching!

Read more…