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Back from FOSDEM 2017

  2017-02-13  |     |    4 Comments

For the third year some of us from Bitcraze visited Fosdem, the biggest open-source European conference. Like the other years we enjoyed being there a lot and we had a great time hanging-out with community members like Fred.

Fred presented a great lightning talk about the news in the Crazyflie galaxy, the video and slide are already available. 

Arnaud talked about the Loco positioning system. The talk and the demo, went well. Unfortunately the video from the talk is not available yet, we will tweet it and add it to this post as soon as it is online.

The Loco Positioning talk was a great opportunity for us to test the most recent bleeding edge additions to the Crazyflie autonomous algorithms. We flew the new non-linear controller from Mike Hammer using trajectory generation from Marcus Greiff. The non linear controller uses setpoints not only of position but also of velocity and acceleration to control the Crazyflie. This is where trajectory generation is useful: if you can generate a trajectory and calculate position, velocity and acceleration over time, you can feed all this information to the controller and the controller will be able to do a much better job following your trajectory. This enabled us to fly the Crazyflie fairly aggressively the week before the FOSDEM talk:

In this video the Crazyflie is accelerating to about 2g continuously to keep the trajectory. We were a bit concerned to fly such aggressive maneuvers in public without more testing so we designed a slightly safer demo the night before the talk in our hotel room:

This trajectory was successfully flown in the demo and shows the performance of this new controller. There has been a lot happening with the Crazyflie control algorithms lately: Marcus, Mike and Wolfgang have all made new controllers and Marcus has developed an on-board trajectory generator. There is still some work required in the firmware architecture to merge these into Master, but we hope this can be done in the coming weeks. Follow the Crazyflie firmware commits and github tickets if you are interested in the progress.

Crazyflie on the catwalk at Berlin Fashion Week

  2017-02-06  |     |    Leave a comment

During the fall of 2016 fashion designer Maartje Dijkstra have in collaboration with music producer Beorn Lebenstedt (Newk) and engineer Erik Overmeire been working with the creation “TranSwarm Entities”, a dress made out of 3D prints accompanied by autonomously flying Crazyflies. The project was made during the Fashion Fusion Lab, a three-month workshop in which selected teams got to work on their fashion concepts. Maartje and her team used our Loco positioning system to enable 4 Crazyflies to do a “dance” around the dress during the show.

 

Copyright Fashion Fusion

Here is how Maartje describes the creation:

“The sculptural high fashion dress is totally build up out of small fragments (bird skulls), like cells building an organism.The parts are manual 3D printed and after printing all connected together by hand with polyester wires and green leather. The technology part is integrated in a special way. 4 small drones, that have given the same black 3D printed appearance as the dress, fly up from places inside so it looks like parts of the dress are flying away.The drones fly on the beats and melodies of music producer Newk around the model creating a little swarm. The shoes are digital 3D printed but finished manually.”

The finalists from the Fashion Fusion Lab got to compete during the Berlin Fashion Week at the “Fashion Fusion Challenge” and we are happy to announce that Maartje together with her team got the third place! 

We at Bitcraze are very happy for Maartje and her team and think it’s very exciting to see the Crazyflie 2.0 and the Loco positioning system being used in such a different context. It shows again the potential for future applications and how versatile the Crazyflie and the Loco positioning system is. 

Here is a video showing the dress:

New decks and presentation at FOSDEM 17

  2017-01-30  |     |    Leave a comment

In this beginning of 2017 we are proud to announce that there are two new decks for the Crazyflie 2.0.

The first one has been in the works for quite some time, it is the Micro SD card deck. It enables read and write access to a SD-Card from the Crazyflie firmware (where we have also implemented FAT filesystem support). Our first use case for this deck has been to implement high speed logging of the IMU sensors: the SD-Card has much higher bandwidth than the radio so it allowed us to log all the sensor values for later analysis. Another use-case could be to read an autonomous sequence from a file on the SD-Card and implement fully autonomous sequencing in the Crazyflie when used in the Loco Positioning System for example. The SD-Card deck is already available on Bitcraze web-shop.

The Second deck is the Z-Ranger deck, it is a laser time-of-flight ranging deck that measures the distance to the ground. We talked about this deck in a previous post. The manufacturing of the deck should be finished soon and so it will be available in our shop shortly. When using this new deck, the altitude hold stability between 0 and 1.5 to 2m height is greatly improved.

On a final note, FOSDEM 2017 is this coming up this weekend and we are looking forward to meet you there. There will be two presentations related to the Crazyflie, if you want to meet us come at these presentations or get in touch in the comment or by mail. The two presentations are:

We hope to see you there!

News from the comunity

  2017-01-16  |     |    2 Comments

Quite a lot has happened in the community in the latest month so we though we would dedicate this Monday post to you :-).

On the firmware side, the loco positioning system has sparked a lot of contribution. Most prominently is the Extended Kalman Filter by Mike Hammer and later improvement by multiple contributors. The Crazyflie is getting more stable and capable week after week which is awesome. Wolfgang from USC has also pushed enhancement coming from its CrazySwarm which will one day gives to everyone the capability to fly big Crazyflie swarm more easily.

On the clients side, we just pushed a new version of the iOS app to the app-store. The main improvement is the new tilt control mode implemented by EMart002 and beta-tested by a community member.

There has also been a new release of the Android client by Fred. This new version adds support for log and param using the Crazyradio. This way it is possible to get telemetry from the Crazyflie like the battery voltage and there is an experimental implementation of altitude-hold when using gamepad.

Running a beta (test-flight) version for the iOS client has been a good experience as it allowed to get direct feedback on functionalities. If there is interest we could release and announce beta versions for both Android and iOS in the future.

Finally last but not the least, there will be a new Crazyflie client in town: The Crazyserver created by Mike Hamer and written in go. It is a cross-platform, install-less, dependency-less server for a fleet of Crazyflies. It exposes a language-independent API, an HTTP rest API, to be able to connect and control any number of Crazyflie from any programming language. It will also include sockets (UDP, TCP and Websockets) to carry real-time data like setpoint and telemetry. It is still very much work in progress and not ready for real-world usage but if you are curious and/or would like to help check the code is on github.

 

Bitcraze, Crazyflie and Loco Positioning System at FOSDEM17

  2017-01-09  |     |    Leave a comment

For the third year we will be at FOSDEM on Saturday 4 and Sunday 5 February 2017 in Brussels. The last two years we have been present and Fred, the Android client maintainer, has had a lightning talk about the Crazyflie.

This year Fred will present a lightning talk about “News from the Crazyflie universe” and Arnaud will have a talk about the Loco Positioning System in the embedded dev-room. The LPS talk will contain a demo of one or more autonomous Crazyflies.

If you are planing at being at FOSDEM and want to meet with us just tell us in the comment, we would be really happy to meet Crazyflie users. There will be almost all of the Bitcraze team and we will have Crazyflie and a Loco Positioning System so it might even be possible to do some flight or demo on the side.

Getting started and get involved

  2016-12-26  |     |    Leave a comment

So you have opened your Christmas present and found your long wished-for Crazyflie. Congratulations! Or maybe you have had your Crazyflie for a while and want to play with it during the holidays? In this blog post we will give you some pointers on where to find information and inspiration.

 

Getting started

You can find all our getting started guides in the “Tutorials” menu on www.bitcraze.io. Take a look at “Getting started with the Crazyflie 2.0” to see how to assemble the kit and take off for your first flight. If you have an expansion deck you will also find a guide for how to install it.

Development

When you are comfortable flying the Crazyflie you might feel that it is time for the next step, to make use of the flexibility of the platform. After all it is designed to be modified!

Check out the “Getting started with development” tutorial to set up your development environment, build your first custom firmware and download it to the copter.

Maybe you want to add a sensor or some other hardware? Heat up your soldering iron and dive in to it! Find more information about the expansion bus on the wiki. The wiki is the place to look for all product and project documentation.

All source code is hosted on github.com/bitcraze and this is also where you will find documentation related to each repository. 

Projects

Looking for inspiration for a project? Take a look at hackster.io or read our blog posts. The video gallery contains some really cool stuff as well as our You Tube channel.

Contribute!

Open source is about sharing, creating something awesome together and contribute to the greater good! Whenever you do something that you think someone else could benefit from, please contribute it! If you were curious or confused about something, someone else probably will too. Help them by sharing your thoughts, insights and discoveries.

Why not

Need help?

Can not find the solution to a problem? Don’t understand how or what to do? Have you read all documentation and are still confused? Don’t worry, head over to the forum and check if someone else had the same problem. If not, ask a new question on the forum and get help from the community.

Happy hacking!

Merry Christmas from Bitcraze!

  2016-12-19  |     |    Leave a comment

This year we decided to do a short Merry Christmas video. The video was done during one chaotic evening last week were both time and technology seemed to be against us. We are anyway happy with the result which we hope will spread some Christmas joy!
 

 
PS. All flights, except the first take-off, where autonomous using the loco positioning system. Code and documentation to come later ;-). DS

Merry Christmas from all of Bitcraze!

Bosch developed MEMS sensor deck for the Crazyflie

  2016-12-13  |     |    6 Comments

At FOSDEM 2016 we met someone from Bosch Sensortec, he was very interested by the Crazyflie and got one. Apparently his college liked the Crazyflie too because soon later we where contacted by Bosch that wanted to make a deck for the Crazyflie containing a brunch of there sensor. We have been tweeting about this board before and now we just pushed the drivers for some of the sensors into the Crazyflie main branch.

The deck has an impressive list of sensor onboard:

  • BMI055: 6 Axis gyro and accelerometer, with closed loop technology gyroscope
  • BMI160: 6 Axis gyro and accelerometer
  • BMM150: 3 Axis magnetometer
  • BMP285: Pressure sensor
  • BME680: Environmental sensor (air, pressure, humidity, temperature).

Thats a lot of data, and there is also an non-populated footprint for a BMF055 which is a BMI055 and an Atmel ARM Cortex-M0 in the same package, this is something that could be very interesting to play with in the future. The drivers and the integration are still in early stage but what has been pushed so far is support for the BMI055 and BMI160. We look forward to tuning those sensors and testing the others as well!

Bosch has made most of the work with this deck them selves and we have provided mainly guidance and support, a big benefit of open source! That has been working great and it has been very fun working with them. We are not sure if this is going to be part of a product yet, as in releasing a deck full of sensors. Please tell us what you think and if anyone would have use for such deck.

VL53L0x expansion deck

  2016-12-05  |     |    4 Comments

Most of the time we have a few prototypes lying around that we’re working more or less on. Sometimes some of these make it into a product if we feel that they might be useful or fun for the community, like for instance the SD-card. Now it’s time for another prototype to be moved to manufacturing, a deck with VL53L0x laser ToF distance sensor.

On the Crazyflie 2.0 (and Crazyflie 1.0 10-DOF) we have a pressure sensor mounted to help control the altitude of the platform. Since air pressure is moving around a lot and the measurement is noisy it’s been very hard to get a rock-solid altitude hold working (although it’s getting closer). Already back when ST released the VL6180X we were looking at it, but the range was too short (10cm max). So when ST released the VL53L0x which has longer range (200cm max) we though this might be a good deck for the Crazyflie 2.0.

So we have a working prototype and thanks to stephanbro and Marcus Grieff we also have the firmware to use it with the Kalman filter. We are currently working at making it work together with the pressure sensor with the current altitude-hold mode.

Currently we’re working on verifying the hardware to make sure the power supply is good enough for it, but then the next step is production. Hopefully it will be available in a couple of months :-) Below is a picture of the current prototype.

VL53

First Crazyflie swarm flying with TDoA in Loco Positioning Sytem

  2016-11-28  |     |    2 Comments

Last week we reached a milestone for our Loco Positioning System: we got 5 Crazyflie 2.0 to fly in a swarm with Time Difference of Arrival measurements. This is a great step closer to making the LPS leave the early-access state.

Until now, positioning has been done using a method called Two Way Ranging (TWR). The advantage of TWR ranging is that it allows us to easily get ranges to the anchors by actively pinging them in sequence. Based on these ranges we can then calculate the current Crazyflie position and control the Crazyflie to move to a wanted position. The big drawback though is that since each Crazyflie has to actively transmit packets to ping anchors, flying many Crazyflie means sharing the air and so the more we want to fly the less ranging each Crazyflie can do. In other words: it does not scale.

TDoA measurement consist of measuring the difference of flight time between packets coming from different anchors and this is harder to achieve since the anchor clocks must be synchronized to each other. The killer feature of TDoA is that it can be implemented using unidirectional packet sent from the anchor system and received by the tag/Crazyflie. It means that as soon as you get one Crazyflie flying with TDoA, you can get as many as you want since the Crazyflies do not have to transmit anything.

This is what happened last week: on Thursday evening we got 1 Crazyflie to fly with TDoA measurements. On Friday we tried 3 and then 5 without much effort. It was just matter of modifying the ROS launchfile to connect more crazyflies, a copy-paste operation.

Then

There still seems to be a margin for progression to get even more stable flight with TDoA and we are also working on making the LPS and Swarm work with our Python client which will make it easier to use outside a robotic lab.

If you want to try the (very experimental!) TDoA mode with your loco positioning system we have documented how to get it to work on the wiki.

Thanks a lot to the growing community that is supporting us and allow us to move faster towards a Crazyflie swarm.