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Bitcraze at ICRA 2025

  2025-06-09  |     |    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.

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.

Crazyflies locating threats in urban environments

  2025-05-26  |     |    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!

RIG and other adventures

  2025-03-10  |     |    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.

Release 2025.02

  2025-02-24  |     |    Leave a comment

We’re happy to announce that release 2025.02 is now available. This update includes fixes and improvements for the Crazyflie 2.1 Brushless, along with stability enhancements for the AI-deck.

Release overview

crazyflie-firmware release 2025.02 GitHub

crazyflie2-nrf-firmware release 2025.02 GitHub

aideck-esp-firmware release 2025.02 GitHub

aideck-gap8-examples release 2025.02 GitHub

cfclient (crazyflie-clients-python) release 2025.2 GitHub, PyPi

cflib (crazyflie-lib-python) release 0.1.28 GitHub, PyPi

Major changes

  • Automatically disarm Crazyflie 30 seconds after landing if manual arming is required
  • Calculate latency, receive uplink RSSI, calculate bandwidth congestion and packet rate in Python library
  • Improved AI-deck GAP8 initialization stability by delaying boot by 5 seconds if the deck is attached
  • Improved AI-deck WiFi streamer stability
  • Improved Crazyflie 2.1 Brushless platform default settings and parameters
  • Crazyflie 2.1 Brushless ESC flashing fixes
  • Modernize Python packaging

Brushless’s feedback

  2025-02-04  |     |    Leave a comment

It’s hard to believe it’s already been almost a month since the Crazyflie 2.1 Brushless was released. We know some of you have already had the chance to take it for a spin, and we’re really excited to hear what you think.

Here at the office, we have started using them a lot – to discover gaps in the documentation, to test our new features, or simply to make nice trajectories during a Fun Friday as shown here:

We’re constantly amazed by it and the new capacity it brings… But, interestingly, we haven’t received many support questions so far… which has us wondering—did we accidentally make it too good? Jokes aside, we’d love to get your thoughts! Whether you have feedback, questions, or just want to share your experience, we’re all ears.

We have a quick form for you here to fill out – it takes a couple of minutes and would help us a lot:

https://docs.google.com/forms/d/e/1FAIpQLSfjnTdUQtCEv9isk4UbASLbe1AxESGtT8Z2q9OfSba-fxYg7g/viewform?usp=sharing

Of course, we’re always available by email if there is more you wish to say: contact@bitcraze.io.

Looking back at 2024

  2024-12-23  |     |    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
The optimized brushless motor

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.

ROSCon
ICRA

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.

Midsummer lunch with the team
Christmas-themed Bitcraze office

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!

Dr. Kim’s last Fun Friday Project

  2024-12-09  |     |    2 Comments

Hi everyone! I have a bit of news to share… I’ve decided to leave Bitcraze at the end of 2024. But not before I share with you my latest Fun Friday project that I’ve tried my best to finish up before I leave before my Christmas holiday in December.

Frankensteining the Pololu Robot with the Crazyflie Bolt

During the ROSCon talk about the lighthouse system (see the recording here), I’ve already shown a small example of how the lighthouse system could be used on other robots as well. Here you see a Pololu RPI 2040 (the hyper edition of course), with a slimmed down Crazyflie Bolt and a Lighthouse deck. The UART2 port on the Bolt (pinout is the same as Crazyflie) is interfacing with the UART0 connection on the Pololu (pinout). Then the Pololu’s 3v3 is connected to the vUSB and GND to GND (obviously), so 4 wires in total. Technically, the 3v3 port is not supplying enough power for the Crazyflie on paper, but it seemed to be enough as long as the Crazyflie Bolt doesn’t have motors connected it should be fine. But if anyone would like to do a driving-flying hybrid with this combo, you might need to check the specifications a bit closer. For now, just ignore the red low-battery LED on the Bolt, but if you see it restarting then perhaps give the Pololu a fresh set of batteries.

Since the Pololu RPI 2040 doesn’t have any wireless communication, this can be done through the Crazyflie Bolt and the Crazyradio. I’ve made an app layer variant for the Bolt to forward state estimates and velocity commands; however, it did require a bit of an extra logging variable in the firmware itself. But this allows me to control the Pololu through the CFclient! Since it’s using velocity commands, this means that the mobile app is out though, but perhaps if anyone is interested in getting this rolling, let me know. Also, the screen shows the current X, Y, Z, and yaw estimate of the Bolt transferred to the Pololu with the commands that I’ve given it.

I’d like to have connected this to a differential drive controller to make use of the position setpoints, but unfortunately the AA batteries ran out at the office and I was unable to complete this by the last day. It would have been great to use the Lighthouse positioning for this. Perhaps in the next coming months, I can try to continue with it and have my cats chase an autonomous robot around the house, who knows! If anyone is interested in playing around with this, these are the repositories/branches for both the Bolt and the Pololu:

What is next?

First of all, I’ll take a long holiday in the US, first visiting New York (first time) before I hop over to Tulsa and Santa Barbara to visit family. Early 2025 I’ll be taking a long break, or a mini sabbatical of sorts, where I plan to work on some personal projects but mostly have a breather. I haven’t had a break like this in over 15 years, and given a tough 2023, I can definitely say that I’ve deserved some time off. What will happen after, I will hopefully figure out then, but for sure I will be continuing to co-lead the Aerial Robotics Interest Group at ROS and helping out in support of the Crazyswarm2 project.

I’d like to thank my colleagues at Bitcraze for an amazing 5 years here in Malmö, Sweden, and everyone that I was able to meet through them. I’ve learned a lot in terms of joint software development, code maintenance, community interaction, and, most importantly, having fun during work. I also will never forget the support I received while I was going through cancer treatment, and for that I’m very grateful. I wish you all the best and I hope the Crazyflie continues to thrive, saving more PhD projects as it did mine. Thank you.

New recruitment at Bitcraze

  2024-11-18  |     |    Leave a comment

It’s been a while since I last talked about hiring! We successfully onboarded our most recent recruit, and now it’s time to start planning for the future.

One of our challenges as a team is that we’re very heavy on engineers and developers. While that’s fantastic for building products, it means we lack expertise in other important areas. That’s why we’re now shifting our focus to bringing in talent to help fill those gaps. We’ve partnered with a recruitment agency once again to help us find the right people for the job.
We’re currently hiring for two distinct roles—here’s what we’re looking for!

Technical sales lead

You will be responsible for developing and implementing sales strategies while exploring both new and existing markets. You’ll take the lead in driving sales and acquiring new customers, becoming the company’s go-to expert on marketing and sales tactics. Your day-to-day tasks will include supporting business development, optimizing sales processes, and proposing effective marketing strategies. This role is perfect for someone with a background in technical sales with a strong strategic mindset and a sense of responsibility.

You can read more about it here.

Technical success engineer

We’re looking for a Technical Success Engineer to provide our customers with technical guidance and product expertise. This role involves offering first-line support, creating documentation and tutorials, and assisting with tech-focused sales efforts. The goal is to ensure a smooth and seamless customer experience while building strong client relationships. It’s an ideal position for a “social developer”—someone with a solid technical background who also excels in communication and enjoys engaging with others.

You can read more about it here.

Both positions are full-time and based at our office in Malmö, Sweden. If you’re curious about why you should join our team, I’ve already shared some of the many reasons why I love being part of Bitcraze.

If you’re interested or have any questions, please send an email to fredric.vernqvist@techtalents.se or contact us at contact@bitcraze.se.

Link performance metrics

  2024-10-28  |     |    Leave a comment

We are excited to announce that we are working on several new link performance metrics for the Crazyflie that will simplify the troubleshooting of communication issues. Until now, users have had access to very limited information about communication links, relying primarily on a “link quality” statistic based on packet retries (when we have to re-send data) and an RSSI channel scan. Our nightly tests have been limited to basic bandwidth and latency testing. With this update, we aim to expose richer data that not only enables users to make more informed decisions regarding communication links but also enhances the effectiveness of our nightly testing process. In this blog post, we will explore the new metrics, the rationale behind their introduction, and how they will improve your interaction with the Crazyflie. Additionally, we will be holding a developer meeting on Wednesday November 13th to discuss these updates in more detail, and we encourage you to join us!

“Link Quality”—All or Nothing

Until now, users of the Crazyflie have had access to a single link quality metric. Implemented in the Python library, this metric is based on packet retries—instances when data packets need to be re-sent due to communication issues. This metric indicates that for every retry, the link quality drops by 10%, with a maximum of 3 retries allowed. As a result, the link quality score usually ranges from 70% to 100%, with a drop to 0% when communication is completely lost. However, as packet loss occurs, users often experience a steep decline, commonly seeing 100% when packets are successfully acknowledged or dropping to 0% when communication is completely lost.

Client representation of link quality; no link, yes link

The current link quality metric has served as a basic indicator but provides limited insight, often making it difficult to gauge communication reliability accurately. Recognizing these limitations, we’re introducing several new link performance metrics to the Crazyflie Python library, designed to provide a far more detailed and actionable view of communication performance.

What’s Coming in the Upcoming Update

The first metric we are adding is latency. We measure the full link latency, capturing the round-trip time through the library, to the Crazyflie, and back. This latency measurement is link-independent, meaning it applies to both radio and USB connections. The latency metric exposed to users will reflect the 95th percentile—a commonly used measure for capturing typical latency under normal conditions.

Next are several metrics that (currently) only support the radio link. For these, we distinguish between uplink (from the radio to the Crazyflie) and downlink (from the Crazyflie to the radio).

The first is packet rate, which simply measures the number of packets sent and received per second.

More interestingly, we are introducing a link congestion metric. Whenever there is no data to send, both the radio and the Crazyflie send “null” packets. By calculating the ratio of null packets to the total packets sent or received, we can estimate congestion. This is particularly useful for users who rely heavily on logging parameters or, for example, stream mocap positioning data to the Crazyflie.

The Received Signal Strength Indicator (RSSI) measures the quality of signal reception. Unlike our current “link quality” metric, we hope that a poor RSSI will serve as an early warning signal for potential communication loss. While RSSI tracking has been possible before with the channel scan example, this update will monitor RSSI in the library by default, and expose it to the user. The nRF firmware will also be updated to report RSSI by default. Currently, we only receive uplink RSSI, that is, RSSI measured on the Crazyflie side.

Work in progress client representation of new link performance metrics

We’ve already found these new metrics invaluable at Bitcraze. While we have, of course, measured various parameters throughout development, it was easy to lose track of the precise status of the communication stack. In the past, we relied more on general impressions of performance, but with these new metrics, we’ve gained a clearer picture. They’ve already shed light on areas like swarm latency, helping us fine-tune and understand performance far better than before.

You can follow progress on GitHub, and we invite you to try out these metrics for yourself. If there’s anything you feel is missing, or if you have feedback on what would make these tools even more helpful, we’d love to hear from you. Hit us up over on GitHub or join the developer meeting on Wednesday the 13th of November (see the join information on discussions).

Release 2024.10

  2024-10-21  |     |    Leave a comment

We are happy to announce that release 2024.10 is now available! Special thanks to our community contributors for their valuable input and code contributions in this release!

Release overview

crazyflie-firmware release 2024.10 GitHub

crazyflie2-nrf-firmware release 2024.10 GitHub

crazyflie2-nrf-bootloader release 2024.10 GitHub

cfclient (crazyflie-clients-python) release 2024.10 GitHub, PyPI

cflib (crazyflie-lib-python) release 0.1.27 on GitHub, PyPI

User upgrade notice

While older versions may still function, users are encouraged to upgrade:

  • Minimum supported Python version changed to 3.10
  • Supported Ubuntu versions changed to 22.04 and 24.04

Major changes

  • Enhanced out-of-tree (OOT) kbuild configuration, allowing users to perform full Kconfig configuration for app layer applications.
  • Introduced recovery functionality, allowing users or scripts to safely re-enable the system after a crash without reboot.
  • Added a timeout for auto-disarming, allowing the system to remain armed during brief landings in manual arming mode.
  • Introduced a workaround for PID derivative kick, improving the performance of the PID controller during large setpoint changes (#1337, #1403).
  • Spiral and constant velocity high-level commander segments (#1410).
  • Changed BLE name format to include part of the NRF MAC address, allowing users to easily differentiate between Crazyflies.

For detailed release notes, check out the individual releases on GitHub. Links can be found in the release overview above.