Alternative Charging Solutions for Crazyflie Swarms

2025-07-21 | Joseph La Delfa | Leave a comment

Today’s blogpost comes from Joseph La Delfa, who is currently doing his Industrial Post-Doc with Bitcraze.

The Qi deck and the Brushless charging dock allow you to start charging a Crazyflie quickly, without having to fiddle with a plug or a battery change. But when you need to charge 10 or more Crazyflies 2.x and don’t want the weight penalty of the Qi deck then some some other solutions are needed.

This blog post is about a couple of chargers I made for the Crazyflie 2.x for my research prototypes. I research interaction design, which often means building something new and then putting in the hands of a user and getting them to try it out. What is important in these scenarios is that when there is unexpected behavior, they don’t think that the prototype is bugging out or broken. One way to prevent this is to make things that have a higher quality to raise the expectations of the user. This can help them stay immersed in the interaction and not look over to me when there is unexpected behavior and say… “is this working properly?”

Wiring Harness for Drone Chi

This charger is essentially a pair of JST 2-pin extensions for a 1S battery charger that I soldered together. Then weaved them through some fake hanging plants. With the drones already looking like flowers for the Drone Chi project, they blended well into the fake plants and all the wires were well hidden. When you wanted to fly, you would disconnect the battery from the wiring harness. Plus it brings the nice experience of picking a flower from a bush before you start flying!

Magnetic Mantle Piece Charger for How To Train Your Drone

This charger allows 10 Crazyflies to charge from their USB ports, but on a bit of a statement piece charger that lived in the lounge room of a group of friends who were participating in a month-long user study during the How to Train Your Drone Project. This charger contained a powered USB hub with cables running through each of the medusa like tubes rising from the base. What made this charger special was the magnetic USB charging adapters (available widely on e-bay, amazon, temu etc) that were plugged into the the USB ports on the drone. These allowed you to securely place the drone on the charger in one action as the magnetic cables integrated into the charger were always close enough to the drone when you set it down, giving you a satisfying * click * every time! They also gave off a eerie blue glow which I think matched the Crazyflie well.

Teaching Robotics with the Crazyflie

2025-07-07 | Aris | Leave a comment

You might already be familiar with the Crazyflie’s presence in numerous publications across various research fields. However, in this blog post, we’ll return to the basics and showcase some robotics concepts that can be taught using our platform.
The Crazyflie has already found its way into several classrooms such as the “Introduction to Robotics” in the Mechanical & Aerospace Engineering Department at Princeton University, the “Introduction to Control of Unmanned Aerial Vehicles” at UC Berkeley and the “Embedded control systems” at Chalmers University of Technology.
Whether you’re designing a robotics course for undergraduates or developing advanced labs for graduate students, here’s some fields where the Crazyflie can help your students grasp the fundamentals of modern robotics.

Basic Drone Principles

How does the quadcopter generate enough thrust? In which direction should the motors spin? How does the shape of a propeller affect performance?
As an introduction to drones and specifically quadcopters, students can explore these basic principles behind how they work. Then, by flying them, they can better understand the three axes of motion, roll, pitch and yaw and even find out their limitations, such as the ground effect.

Control Systems

What is the difference between controllers? How does a different controller tuning affect performance? How does an estimator work? What types of commands can be sent to a drone?
The Crazyflie platform offers a rich “playground” for exploring the stabilization process from sensor acquisition to motor control, that we often call “stabilizer module“. This includes a variety of controllers, estimators and commanders that can be modified to visualize results in the real world. Also, with the firmware being open-source and modular, it is relatively easy to build your own controller or estimator and integrate it to the platform.

Localization

How can a drone know its position and orientation in 3D space? What is the difference between a local and a global positioning system?
With a wide variety of deck sensors and positioning systems, students can find ways to control the Crazyflie through relative or absolute position/attitude commands. The different sensing methods used in these systems are also interesting to explore – for example, IR signals from the Lighthouse Positioning System, UWB radio from the Loco Positioning System, or optical flow data from the Flow deck v2.

Autonomous Navigation

How could the Crazyflie perform a collision-free trajectory? What is the most efficient way of flying from point A to point B?
In the field of autonomous navigation, the Crazyflie can be treated like any other moving robot by applying existing path planning algorithms or testing newly developed ones. Environment-aware problems are always exciting to work on and the Multi-ranger deck makes them feasible.

Swarm Robotics

What happens when you add another Crazyflie to your setup? How could multiple Crazyflies operate in a swarm? How could you make sure that they won’t collide? What is the difference between a centralized and a decentralized swarm?
Scaling a system up is always challenging but also fascinating. The examples provided in our Python library help you get a swarm in the air, but it’s up to you and your students to explore how the Crazyflies should coordinate and cooperate.

Small Drone, Big Educational Impact

The Crazyflie ecosystem is a fully capable robotics lab in the palm of your hand. Its flexibility, safety, and robust API support make it ideal for hands-on learning in a wide variety of robotics fields. Integrating the Crazyflie into a university robotics curriculum, gives students the chance to explore, test, fail, and fly their way to mastery.

Bitcraze at ICRA 2025

2025-06-09 | Rik | Leave a comment

A couple of weeks ago, we were at ICRA 2025 in Atlanta. This year’s ICRA drew over 7,000 attendees, making it the biggest edition yet. We had a booth at the exhibition where we showed our decentralized swarm demo. The setup included a mix of Crazyflie 2.1+ units with Qi charging decks and Crazyflie 2.1 Brushless platforms with our new charging dock. The entire swarm operated onboard, with two Lighthouse base stations for positioning. More details about the setup can be found in the recent swarm demo blog post.

8 Crazyflies flying simultaneously in our decentralized swarm at ICRA 2025

Some of the brushless drones carried our high-powered LED deck prototype to make the swarm more visible and engaging. One of the drones also had a prototype camera streaming deck, which held up well despite the busy wireless environment.

A Different Perspective

This year we were also invited to participate in a workshop: 25 Years of Aerial Robotics: Challenges and Opportunities, where I (Rik) gave a short presentation about the evolution of positioning in the Crazyflie, from webcam-based AruCo marker tracking to the systems we use today.

Usually, we spend most of our time on the exhibition floor, so being part of a workshop like this was a different experience. It was interesting to hear researchers mention the Crazyflie in their work without needing to explain what it is. That kind of familiarity isn’t something we take for granted, and it was nice to see.

Many thanks to all the participants of the workshop '25 Years Of Aerial Robotics: Challenges And Opportunities' that we had the pleasure to co-organise for #ICRA2025. The speakers, young researchers, chairpersons and, of course, the attendees all made it a unique experience🦾 pic.twitter.com/WNfUUYLtop
— GRVC (@grvc_us) May 27, 2025

The workshop also gave us a chance to talk with both established researchers and newer faces in the field. What stood out most was hearing how people are using the Crazyflie in their work today. It’s very rewarding to see how what we do at the office connects with and supports real research.

Catching Up and Looking Around

One of the most rewarding parts of the conference was the chance to connect directly with people using the platform. We talked to many users, both current and past, and saw new research based on the platform. It was also great to reconnect with Flapper Drones, who build flapping-wing vehicles powered by the Crazyflie Bolt. And it was nice to see HopTo on the exhibition floor for the first time. The company is a spin-off from the Robotics and Intelligent Systems Lab at CityU Hong Kong, which published a Science Robotics paper on the hopcopter concept that used a Crazyflie. We also had the chance to catch up with a maintainer of CrazySim, an open-source simulator in the Crazyflie ecosystem. It’s always valuable to connect with people building on top of the platform, whether through research, hardware, or open-source tools.

Wrapping Up

ICRA 2025 was packed with activity. From demoing the swarm, to the workshop, to hallway conversations, it gave us a lot of valuable feedback and insight. Thanks to everyone who stopped by, joined a talk, or came to say hello.

Empowering Innovation in China: Bitcraze and NOKOV Motion Capture Forge a Strategic Partnership

2025-06-02 | Fredrik Ehrenstråle | Leave a comment

As the demand for open, modular, and research-grade robotics continues to grow, Bitcraze is entering a strategic distribution partnership in China, one of the world’s most advanced and fast-evolving markets for robotics and education.

Researchers, educators, and industrial developers in China will benefit from easy access to Bitcraze’s entire product ecosystem. This includes high-performance indoor drones, positioning systems, and modular development tools widely used in academia and R&D across the globe.

Our new exclusive agreement with NOKOV Motion Capture, marks a step forward in expanding access to our autonomous drone systems and robotics development kits across China.

Expanding Access for China’s Robotics Community

Through NOKOV Motion Capture, customers in China gain professional support in Mandarin, short delivery times, and access to official training, demos, and bundled solutions. Together, we’re making it easier than ever for Chinese institutions to explore autonomous flight, precision tracking, and open-source robotics innovation.

A Powerful Integration of Motion Capture and Flight

One of the most exciting aspects of this partnership is the technical synergy between NOKOV Motion Capture’s industry-leading motion capture systems and Bitcraze’s versatile flight platforms. NOKOV Motion Capture’s optical tracking technology is already a staple in academic and industrial research labs throughout China.

By integrating this with Bitcraze’s drones and positioning systems, users can achieve highly accurate, low-latency indoor positioning, conduct repeatable flight experiments with synchronized motion data, and enjoy a seamless workflow from trajectory capture to analysis.

This combination opens up new possibilities for research in fields like robotics control, swarm behavior, artificial intelligence, and simulation.

Supporting Research, Education, and Development

Bitcraze’s systems have earned the trust of top universities and laboratories around the globe. With this partnership, we continue to support Chinese institutions working on:

Swarm robotics and AI research
STEM and engineering education
Indoor navigation and environment interaction
Lightweight aerial prototyping and simulation

We believe in giving innovators the tools they need to experiment freely, iterate faster, and go further.

Start Your Journey with Us

Whether you’re designing new robotic systems or preparing your classroom for hands-on drone-based learning, Bitcraze and NOKOV are here to support your ambitions.

If you’d like to learn more or get started with our products in China, please reach out to NOKOV for local support and information.

https://www.nokov.com/products/robotics/crazyflie-crazyswarm-platform.html

https://en.nokov.com/products/robotics-motion-capture/crazyflie-crazyswarm.html

Together, we’re making robotics innovation more accessible, collaborative, and inspiring for everyone.

Crazyflies locating threats in urban environments

2025-05-26 | Barbara | Leave a comment

As we mentioned in a previous blog post, the last couple of weeks have been full of exciting events in the US. We first began our adventure in Charlotte, North Carolina, where we attended the International Conference on Unmanned Aircraft Systems (ICUAS), as platinum sponsors.

We were especially thrilled to be involved because the final stage of the conference’s competition featured Crazyflies, which played a central role in the challenge.

The ICUAS UAV Competition

This year’s competition simulated a search mission in an urban environment. The goal was for teams to identify ArUco markers placed on multiple obstacles, while maintaining line-of-sight and communication among a swarm of three Crazyflies.

Each team’s UAVs launched from a designated base, navigated a known environment, and attempted to locate several targets. The drones relied on an OptiTrack system for positioning and used the AI deck as a camera for image recognition. Constant communication between the base and all UAVs was required throughout the mission.

The event, organized by the LARICS team, combined both simulation and real-world implementation. Their hard work ensured that competitors could smoothly transition their systems from digital models to actual flying drones. What followed was an intense and fun two-day hackathon.

Although the ICUAS UAV Competition drew interest from 26 teams globally, only five finalist teams made it to Charlotte to run their scenarios with real drones. In the end, it was Team Aerial Robotics from the Indian Institute of Technology Kanpur (IITK) who took home first place—congratulations to them!

While the event went smoothly overall, some communication challenges cropped up—solved creatively by placing a radio in the center of the arena. Battery management was also key, with fully charged packs being a hot commodity to maximize flight time.

Research and Presentations

Alongside the competition, the conference featured a wide range of research presentations. We were proud to see Rik present on the AI deck during a workshop focused on embodied AI.

One of the highlights was the Best Paper Award, which—although we missed the talk, was awarded to a team from Queen’s university using the Crazyflie to simulate drone landings on ocean waves. You can read their fascinating paper here:
https://arxiv.org/abs/2410.21674

Final Thoughts

Overall, ICUAS 2025 was a great experience—full of innovation, collaboration, and of course, plenty of flight time. We’re grateful to the organizers, competitors, and everyone who stopped by our booth. Until next time!

Bitcraze’s conferences in May

2025-04-07 | Barbara | Leave a comment

We’ve got an exciting month ahead – in just a few weeks, we’re heading off to not one, but two amazing conferences! It’s going to be a whirlwind, but we couldn’t be more thrilled to be part of these events, meet fellow robotics enthusiasts, and show off some cool demos. Here’s where you’ll find us:

First stop: ICUAS

We’re kicking things off with ICUAS (International Conference on Unmanned Aircraft Systems), where we’re proud to be official sponsors of the competition. We’ll be present there to help and support the constestants of the competition, that are going to use the Crazyflies in simulation and in real life. The teams will need to deploy a team of UAVs in an urban environment to locate and identify threats.

It’s our first time attending ICUAS, so this is a brand new adventure for us – and we can’t wait to dive in and see what it’s all about!

Next up: ICRA

Just two days after ICUAS wraps up, we’re heading straight to ICRA – this year taking place in Atlanta. You’ll be able to find us at booth 131, right in front of the Tech Talk stage. If you’re attending, definitely come say hi!

We had the honour to be invited to be part of the workshop “25 years of arial robotics: challenges and opportunities“. Rik will talk there on the 23th of May at 16.10; covering Bitcraze’s history and the challenges we’ve faced in positioning a nanocopter – all in just 10 minutes. We’ll also take part in the forum on Undergraduate Robotics Education Programs on the 22th of May. We’ll have a poster presenting the Crazyflie as an educational platform.

These are all fantastic opportunities to highlight what makes our platform special and to exchange ideas with you! If you’ve got a paper or publication featured at ICRA, we’d love to hear about it – email us at contact@bitcraze.io, leave a comment below this post, or drop by our booth.

Demo

We’re bringing back our trusted demo setup – but this time, with more Brushless units and charging docks! It will be a version between what we presented at the last ICRA and what we call “the fish tank demo” we have now at the office.

We’ll also be bringing along some prototypes and new decks we’re currently working on – so if you’re curious about what’s coming next for Crazyflie, this is your chance to get a sneak peek and chat with us about it!

Give us your posters!

Last year, we collected posters from proud participants to decorate the office, and it turned out amazing – so we’re doing it again! If you’ve got a cool poster featuring our products and aren’t sure what to do with it after your presentation, come by our booth. We’d love to swap it for something a little extra special.

All in all, it’s shaping up to be a busy, exciting, and (hopefully) couple of weeks. Whether you’re at ICUAS or ICRA, stop by, chat with us, and see the Crazyflies in action. We’re looking forward to reconnecting with old friends and meeting new ones – see you there!

Bitcraze at HRI 2025 with How To Train Your Drone

2025-03-17 | Joseph La Delfa | Leave a comment

Human Robot Interaction (HRI) is a conference that brings together academics and industry partners to explore how humans are interacting with the latest developments in robotics. The conference is held yearly and brings together the many relevant disciplines concerned with the “H” part (cognitive science, neuroscience), the “R” part (computer science, engineering) and the I part (social psychology, education, anthropology and most recently, design).

This year it was in Melbourne (my home city) and I was so grateful to be given the chance to demonstrate a system from my PhD studies called “How To Train Your Drone” in what was its final hurrah, a retirement party! Running the demo was a pleasure, especially with the supportive and curious HRI crowd at such a well organised event .

The take home message from this demonstration was this:

If you let the end user shape, with their hands, the sensory field of the drone, they then end up with an in-depth understanding of it. This allows the user to creatively explore how the drone relates to themselves and their surrounding environment.

What do we mean by sensory field? Its the area around the drone where it can “feel” the presence of those hand-mounted sensors, represented by the grey and red spheres in the figure below. Initially, the drone has no spheres and therefore cannot respond at all to the user’s movement. But by holding the hands still for a few seconds the user can create a spherical space, relative to the drone where the drone can sense their hands and follow them.

These spheres are “part of the drone’s body”, and so they move with the drone. So in a way you are kind of deciding where the drone can “feel” whilst also piloting it. Should it be sensitive in the space immediately in front of it? Or either side of it?

But shouldn’t it just be everywhere?

Good question! We think the answer is no, and for two reasons:

What we can and cannot sense as humans is what makes us human. It also allows us to understand other humans. E.g. We don’t deliver verbal information directly into other people’s ears at max volume because we have ears and we know that sucks. Nor do we demonstrate how to perform a task to someone with their back turned to us. So by the same token, knowing how a machine senses the world also teaches us how to communicate with it. Furthermore, shaping how a machine can sense the world allows us to creatively explore what we can do with it.
To quote science writer Ed Yong, “Nothing can sense everything and nothing needs to”. Meaning we can get the job done without having to ingest insane amounts of data and even more insane amounts of compute. By cumulatively building an agent’s capacity, in context, with end users, we could actually end up with agents that are hyper specialised and resource efficient. A big plus for resource constrained systems like the Crazyflie and our planet at large.

If you are interested in reading more about this research then please check out this paper (if you like to read) or this pictorial (if you like to look at pictures). Or just reach out in the comments below!

RIG and other adventures

2025-03-10 | Barbara | Leave a comment

This week in Germany

This week, some of us are on an adventure!
Marcus and Tobias will be exploring both the RIG and Embedded World fairs.

RIG showcases the latest innovations in robotics and intelligent systems, while Embedded World is the place to be for cutting-edge embedded technologies. Both events promise amazing demos, insightful talks, and a chance to catch up with some of our collaborators.

Planning to attend either fair? Let’s meet up! We’d love to explore the exhibitions together, chat about cool technologies, or just geek out about the innovations on display. We’ll be wandering through Embedded World on Thursday and hitting RIG on Friday. Send us an email if you’d like to connect – we’re always up for grabbing coffee!

Next May in Atlanta

After our adventures as visitors, we’re thrilled to announce that we’ll be exhibiting at the International Conference on Robotics and Automation (ICRA) 2025! Stop by our booth where we’ll be showcasing our latest demo. We’ll be, as always, available to discuss our newest products, answer your technical questions, and provide insights into how our solutions can transform your robotics applications. We’re also eager to hear your thoughts on what you’d like to see in our upcoming products. Mark your calendars and make sure to find us at Booth #131 – we may even have some presentations in the work, but nothing confirmed yet.

Today in the shop

And, last but not least, the Brushless is now available in a Swarm configuration! Both the Lighthouse Swarm bundle and Loco Swarm bundle have been added to our shop. These new bundles feature all the same components as our standard Swarm packages, but come equipped with the Crazyflie 2.1 Brushless instead of the Crazyflie 2.1+ model.

Bitcrazers at FOSDEM 2025!

2025-01-27 | Arnaud | Leave a comment

Marcus and I are going to visit FOSDEM 2025 at the end of the week. This is a great open-source conference that I visit every year but this year there is a twist: I am part of the organisation of the Robotics and Automation devroom! I am going to give the welcome talk there:

FOSDEM is a conference with many tracks, the main track and devrooms. Devrooms are like mini-conferences: they are handled by a committee that produces a call for participation and handles the schedule for the room. FOSDEM allocates a time slot, a physical room, and video recording for the devroom so that all talks are broadcasted in real-time and recorded.

Since my first visit to FOSDEM in 2015, we have been thinking about the lack of a dedicated devroom for robotics: a lot of robotics, at least in research, is open source. This is in part thanks to ROS, which allows for easily sharing modules and algorithms between projects, but it also applies to things like flight stacks that are often open-source. So we took it upon ourselves to organize what we wanted, a robotics-dedicated devroom.

We started last year, at FOSDEM 2024, by organizing a robotics Bird of Feather with Kimberly. These are impromptu meetups that can be organized by booking a time on the spot for a couple of dedicated rooms. There, we had some really nice discussions with fellow robotics enthusiasts and figured out that there was indeed quite some interest in robotics at FOSDEM and that we were enough interested parties to organize a devroom.

If you’re interested in open source and/or robotics and you can be in Brussels, Belgium, on the weekend of the 1st and 2nd of February 2025, please join us! The Robotics and Simulation devroom is on Sunday afternoon. I will also be monitoring our Mastodon channel more carefully, so do not hesitate to poke me if you want to meet either me or Marcus, as we will be at the conference both days.

Looking back at 2024

2024-12-23 | Rik | Leave a comment

As 2024 comes to an end, it’s the perfect time to reflect on what we’ve accomplished over the past year. A major highlight has been our work on the Crazyflie 2.1 Brushless. We’re thrilled that it will be available early in the new year! While much of our efforts focused on refining and preparing the platform as a whole, we also introduced some standout features like support for contact charging on a charging pad, perfecting the specially optimized motors, and propeller guards to enhance safety for both users and the drone.

The Crazyflie 2.1 Brushless with propeller guards on a prototype charging pad

Finalizing the integration of the Crazyflie 2.1 Brushless into our software ecosystem and expanding its documentation were key steps in preparing for its launch. These efforts ensure compatibility, improve the user experience, and make the platform more accessible to the community. We’re looking forward to a smooth launch and to seeing how the community will utilize the new platform!

This year, we introduced updates to the Crazyflie 2.1 kit, making the 47-17 propellers the new default and including an improved battery. These upgrades enhance flight performance and endurance, culminating in the release of the Crazyflie 2.1+—an optimized iteration of our established platform.

The Crazyflie 2.1 Brushless featured on the cover of Science Robotics vol. 9, no. 92

Community

In 2024, Bitcraze had an action-packed year, engaging with the robotics community through numerous conferences, workshops, and live events.

In May, we attended ICRA 2024 in Yokohama. We collected several research posters that now proudly feature at the office. Kimberly presented at the Robotics Developer Day, where she won Best Speaker Award for her impressive live hardware demos with ROS2. We co-organized the ‘Aerial Swarm Tools and Applications’ workshop at RSS 2024 in Delft. Arnaud and Kimberly shared insights on demo-driven development on an episode of OpenCV Live!. Additionally, we had a booth at ROSCon ’24 in Odense, connecting with the vibrant ROS community and showcasing our latest developments.

And don’t forget the developer meetings, where we shared some more behind the scenes information and collected invaluable feedback from the community.

We also released a new edition of our research compilation video, showcasing some of the coolest projects from 2023 and 2024 that highlight the versatility and impact of the Crazyflie platform in research.

Team

In the past year, Bitcraze saw significant changes within the team. in February, Rik rejoined the team. Tove started at Bitcraze in April. Mandy, with whom we’ve already worked extensively over the years, joined as our production representative in Shenzen. At the end of the year, we said goodbye to Kimberly, whose contributions will be deeply missed. Additionally, we had Björn with us for a few months, working on his master’s thesis on fault detection, and Joe continued his industrial postdoc at Bitcraze that began in December 2023. Looking ahead, Bitcraze is hiring for two new roles: a Technical Sales Lead and a Technical Success Engineer, to support our ongoing projects and customer collaborations.

As we close the chapter on 2024, we’re proud of the progress we’ve made, the connections we’ve strengthened, and the milestones we’ve reached. With exciting launches, new faces on the team, and continued collaboration with our community, we’re ready to soar to even greater heights in 2025. Thank you for being part of our journey!