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.
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.
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.
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).
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!
It’s now become a tradition to create a video compilation showcasing the most visually stunning research projects that feature the Crazyflie. Since our last update, so many incredible things have happened that we felt it was high time to share a fresh collection.
As always, the toughest part of creating these videos is selecting which projects to highlight. There are so many fantastic Crazyflie videos out there that if we included them all, the final compilation would last for hours! If you’re interested, you can find a more extensive list of our products used in research here.
The video covers 2023 and 2024 so far. We were once again amazed by the incredible things the community has accomplished with the Crazyflie. In the selection, you can see the broad range of research subjects the Crazyflie can be a part of. It has been used in mapping, or swarms – even in heterogeneous swarms! With its small size, it has also been picked for human-robot interaction projects (including our very own Joseph La Delfa showcasing his work). And it’s even been turned into a hopping quadcopter!
Here is a list of all the research that has been included in the video:
Energy efficient perching and takeoff of a miniature rotorcraft Yi-Hsuan Hsiao, Songnan Bai, Yongsen Zhou, Huaiyuan Jia, Runze Ding, Yufeng Chen, Zuankai Wang, Pakpong Chirarattananon City University of Hong Kong, Massachusetts Institute of Technology, The Hong Kong Polytechnic University
But enough talking, the best way to show you everything is to actually watch the video:
A huge thank you to all the researchers we reached out to and who agreed to showcase their work! We’re especially grateful for the incredible footage you shared with us—some of it was new to us, and it truly adds to the richness of the compilation. Your contributions help highlight the fantastic innovations happening within the Crazyflie community. Let’s hope the next compilation also shows projects with the Brushless!
This week, we have a guest blog post from Scott at Droneblocks.
DroneBlocks is a cutting-edge platform that has transformed how educators worldwide enrich STEM programming in their classrooms. As pioneers in the EdTech space, DroneBlocks wrote the playbook on integrating drone technology into STEM curriculum for elementary, middle, and high schools, offering unparalleled resources for teaching everything from computer science to creative arts. What started as free block coding software and video tutorials has become a comprehensive suite of drone and robotics educational solutions. The Block-Coding software still remains free to all, as the DroneBlocks mission has always been to empower educators and students, allowing them to explore and lead the way. This open-source attitude set DroneBlocks on a mission to find the world’s best and most accessible micro-drone for education, and they found it in Sweden!
Previously, DroneBlocks had worked alongside drone juggernaut DJI and their Tello Drone. The Tello was a great tool for its time, but when DJI decided to discontinue it with little input from its partners and users, it made the break much easier. The hunt began for a DJI Tello replacement and an upgrade!
Bitcraze’s choice to build Crazyflie as an open platform had their drone buzzing wherever there was curiosity. The Crazyflie was developed to fly indoors, swarm, and be mechanically simplistic. DroneBlocks established that the ideal classroom micro-drone required similar characteristics. This micro-drone needed to be small for safety but sturdy for durability. It also needed to be easy to assemble and simple in structure for students new to drones. Most importantly, the ideal drone needed to have an open line of software communication to be fully programmable. Finally, there had to be an opportunity for a long-lasting partnership with the drone manufacturer, including government compliance.
After extensive searching and testing by DroneBlocks, the Crazyflie was a diamond in the rough – bite-sized and lightweight, supremely agile and accurate, reliable and robust, and most importantly, it was an open-source development platform. The DroneBlocks development team took the Crazyflie for a spin (or several) and with excitement, it was shared with the larger curriculum team to be mined for learning potential. It was promising to see Crazyflie’s involvement in university-level research studies, which proved it meant business. DroneBlocks knew the Crazyflie had a lot going for it – on its own. The team imagined how, when paired with DroneBlocks’ Block Coding software, Flight Simulator, and Curriculum Specialists, the Crazyflie could soar to atmospheric heights!
Hardware? Check. Software? Check. But what about compatibility? DroneBlocks was immediately drawn to the open communication and ease of conversation with the Bitcraze team. It was obvious that both Bitcraze and DroneBlocks were born from a common thread and shared a mutual goal: to empower people to explore, investigate, innovate, research, and educate.
DroneBlocks has since built a new Block Coding interface around the Crazyflie, allowing students to pilot their new drone autonomously and learn the basics of piloting and coding concepts. This interface is offered with a brand new drone coding simulator environment so students can test their code and fly the Crazyflie in a virtual classroom environment.
The Crazyflie curriculum currently consists of courses covering building, configuring, and finally, programming your drone with block coding (DroneBlocks) and Python. DroneBlocks’ expert curriculum team designed these courses to enable learners of all ages and levels to learn step by step through video series and exercises. New courses around block coding and Python are in constant development and will be continuously added to the DroneBlocks curriculum platform.
Crazyflie Drones now headline DroneBlocks’ premiere classroom launch kit. The DroneBlocks Autonomous Drones Level II kit encompasses everything a middle or high school would need to launch a STEM drone program, including the hardware, necessary accessories, and safety wear paired with the DroneBlocks software and curriculum. As a result, thousands of new students have entered the world of Drones and programming thanks to the Bitcraze + DroneBlocks partnership.
DroneBlocks has become an all-inclusive drone education partner for engaging and innovative learning experiences—and the Crazyflie delivers this by being a cutting-edge piece of hardware in a clever package.
If you know a little about Sweden, you know about Midsommar. Nothing like the 2019 horror film (thankfully), though we do wear flower crowns and dance around the pole. It’s usually an occasion to celebrate with family (and alcohol) those long days and short nights. We actually celebrated a little bit early today with a nice team barbecue.
Midsommar is next Friday, and it marks the official kickoff to summer here in Sweden. That also means that for the coming 2 months, Bitcraze will be operating with a slightly smaller team. So, what does that mean for you? This should not impact you too much, of course, but here are the most important things to note:
Developer Meetings: First up, our regular developer meetings will be on hiatus during July and August. It’s a great time for everyone, including you, our regular attendees, to take a breather. We’ll be back in action come September, resuming our usual schedule of one meeting per month.
GitHub: With fewer team members around, our response time on GitHub discussions might be a bit slower. We strive to answer every question, but with less manpower, some issues might only get resolved when the person with the right expertise returns from their vacation. We appreciate your patience and understanding during this time.
Orders: Shipping and deliveries should have the same pace, so don’t worry about your order coming on time, we’ve got that covered!
Ongoing projects and maintenance
Our focus during the summer will shift primarily to maintenance and continuing work on ongoing projects. We’re putting the final touches on the Brushless project of course, and will keep working on its charger solution too.
We’re excited to announce our participation in Robotics Developers Day on July 5th. We’re not only sponsors of this event, we’re also thrilled that Kimberly will be hosting a live learning session about ROS 2 on the Crazyflie.
For us at Bitcraze, summer is a wonderful opportunity to slow down a bit and focus on projects we don’t usually have time for. This could mean diving deeper into learning RUST, reorganizing the office, or trying some prototypes out. It’s a chance to reset and prepare for the busy months ahead.
We hope you have a fantastic summer filled with sunshine, relaxation, and lots of new adventures. Glad Midsommar, as we say here!
From the beginning of the company, we’ve always loved to join in at conferences. Only at a conference do you get the opportunity to show our products, meet our users or other tech-oriented people, learn about what others are doing, and let’s not forget the chance to discover a new place!
This year, we’ll be present at ICRA Yokohama – it’s in just 3 weeks. We’ll have a booth there (IC085 if you’re looking for us). We’ll be showing our autonomous demo with a twist just like we have shown last time, so please check the event page. This demo is extremely impressive and we’ve been improving on it each time we’ve shown it – beginning in our latest Japan trip and lastly at the last ICRA too. What’s new?
… and perhaps some more prototypes of whatever we managed to bring in our suitcase!
We’re really excited to be showing that and receive feedback, but also in hearing about what our users have been doing. ICRA is always a perfect place to catch up on all the amazing papers and publications featuring our hardware, and we couldn’t be prouder of all the cool stuff we’ve seen so far. We’re so proud, in fact, that we want to be able to show off! So, if you have a paper or a publication featured at ICRA, let us know – you can write us an email at contact@bitcraze.io, leave a comment below this post, or pass by our booth.
In fact, we’re prepared to make a deal. If you have a nice poster featuring our products and don’t know what to do with it once you’ve presented it, pass by our booth! We’re ready to swap them for something extra special. We plan to have a “hall of fame” at the office featuring your awesome work – in fact, it’s an idea we had last ICRA when someone just offered us their posters. Now, we’d like to cover our walls with them!
The corridor leading to the kitchen – we have space to show off the awesomeness!
So, whether you’re a seasoned conference-goer or a first-time attendee, don’t hesitate to wsing by our booth, say hello, and discover our newest demo! We hope to see you there.
Dev meeting
Next developer meeting is going to be on the 8th of May – we traditionally have a dev meeting every first Wednesday of the month, but this time it happens to be on the 1st of May which is a holiday here in Sweden. So already prepare your calendar for the 8th of May at 15.00 CET, and stay tuned for more info on which topic we’ll talk about!
Crazyflies back in stock !
You may have noticed that the Crazyflies have been out of stock for some time now. After some adventures, we are now fully back in stock with most of our bundles and products available in the shop!
You may have noticed that the HQ propellers, which are a part of the thrust upgrade bundle, have been out of stock for quite some time now. I know that many of you are relying on those propellers for the additional 20 grams of thrust they allow, so I have some news – some good, some bad.
Let’s start with the bad news: our partner and manufacturer, unfortunately, faced some problems with the mold they were using for these propellers- we prepared to face the fact that having our thrust propellers as they were before was not possible anymore. With the mold in this state, we could never go back to the same version of those propellers. To be a little dramatic, the high-quality propellers have taken their final spin. We knew it could take some time to find a good solution, and were prepared to communicate about a long-time shortage of the item.
But now for the good news! Thankfully, the replacement mold our partner used proved to be as good as the previous one – and faster than scheduled. Now back in stock, the HQ propeller can fly as well as its predecessor. We tested it and it showed the same characteristics that we’ve come to expect from the thrust upgrade.
So, what’s the real difference? Well, since it maintains the same level of performance, agility, and stability, not much. They have an updated design and have an added “ultralight” in the name (which sounds cooler, doesn’t it?). Those of you with a keen sense of observation will also notice that they have a new SKU – as well as the thrust upgrade bundle.
All in all, this change will have minimal impact on your flying if you’re used to the thrust upgrade bundle. Don’t hesitate to try out this new version and give us some feedback if you have any!
2023 has already begun, and we have some ideas and hopes on what this new year will mean for Bitcraze. Of course, what 2022 has proven to us is that the world is unpredictable; but it doesn’t stop us from dreaming about our future. So here is what’s in our wishlist for 2023!
Products
We dedicated a good part of the winter to get a new, updated and better Crazyradio, that we will present to you sometime this year. Rumor around the office is that it will solve all problems you can think of, related to communication!
And, even though it’s been a long run, we hope to soon get the Big Quad deck and Bolt out of early access. There are still some things to tweak and documentation to write.
The Nimble + should arrive soon in the store, a drone with flapping wings powered by the Bolt and designed by our friends at Flapper Drones.
Prototypes
There’s always a drawer at Bitcraze that’s full of ideas and prototypes. What we lack to make them come true is time ! We are constantly wondering which of those treasures that will be our next product, and I can’t say anything is for certain, but to give you some ideas, we’ve been playing around with the idea of a brushless Crazyflie, a Glow deck, and are definitely updating some of our current decks.
Community
We really enjoyed meeting people at fairs once again after 2 years of staying put. We don’t know at which conference you will be able to catch us (yet), but we’ll most definitely attend at least 2.
And we will not loose track of our users and hope to get feedback and input as much as possible during our dev meetings or even mini-BAMs.
Bitcraze
We’re still actively looking for teammates, and we hope there’s someone out there that will join us in 2023! Send us a CV if you’re interested.
External dependencies
The components crisis hit us hard in 2020, but it seems we’re gradually coming back to normal. While the world is still full of surprises, we’re happy to have enough stability to still be doing what we like, through pandemics or recessions. Of course, we much rather prefer when things are a little less exciting! We’re cautiously optimistic about 2023, hoping that wars will end and that awareness about climate change will bring out the right habits.
Soon we will have our quarterly meeting, where we try to herd and select our passions and ideas into conceivable plans and actions.
We’re never sure if one year is enough to see all of our plans and hopes go through, but 2023 is still brand new with a lot of possibilities, that we plan to grab with passion. May this new year bring you excitement and passion too!
This year, the traditional Christmas video was overtaken by a big project that we had at the end of November: creating a test show with the help of CollMot.
First, a little context: CollMot is a show company based in Hungary that we’ve partnered with on a regular basis, having brainstorms about show drones and discussing possibilities for indoor drones shows in general. They developed Skybrush, an open- source software for controlling swarms. We have wanted to work with them for a long time.
So, when the opportunity came to rent an old train hall that we visit often (because it’s right next to our office and hosts good street food), we jumped on it. The place itself is huge, with massive pillars, pits for train maintenance, high ceiling with metal beams and a really funky industrial look. The idea was to do a technology test and try out if we could scale up the Loco positioning system to a larger space. This was also the perfect time to invite the guys at CollMot for some exploring and hacking.
The train hall
The Loco system
We added the TDoA3 Long Range mode recently and we had done experiments in our test-lab that indicate that the Loco Positioning systems should work in a bigger space with up to 20 anchors, but we had not actually tested it in a larger space.
The maximum radio range between anchors is probably up to around 40 meters in the Long Range mode, but we decided to set up a system that was only around 25×25 meters, with 9 anchors in the ceiling and 9 anchors on the floor placed in 3 by 3 matrices. The reason we did not go bigger is that the height of the space is around 7-8 meters and we did not want to end up with a system that is too wide in relation to the height, this would reduce Z accuracy. This setup gave us 4 cells of 12x12x7 meters which should be OK.
Finding a solution to get the anchors up to the 8 meters ceiling – and getting them down easily was also a headscratcher, but with some ingenuity (and meat hooks!) we managed to create a system. We only had the hall for 2 days before filming at night, and setting up the anchors on the ceiling took a big chunk out of the first day.
Drone hardware
We used 20 Crazyflie 2.1 equipped with the Loco deck, LED-rings, thrust upgrade kit and tattu 350 mAh batteries. We soldered the pin-headers to the Loco decks for better rigidity but also because it adds a bit more “height-adjust-ability” for the 350 mAh battery which is a bit thicker then the stock battery. To make the LED-ring more visible from the sides we created a diffuser that we 3D-printed in white PLA. The full assembly weighed in at 41 grams. With the LED-ring lit up almost all of the time we concluded that the show-flight should not be longer than 3-4 minutes (with some flight time margin).
The show
CollMot, on their end, designed the whole show using Skyscript and Skybrush Studio. The aim was to have relatively simple and easily changeable formations to be able to test a lot of different things, like the large area, speed, or synchronicity. They joined us on the second day to implement the choreography, and share their knowledge about drone shows.
We got some time afterwards to discuss a lot of things, and enjoy some nice beers and dinner after a job well done. We even had time on the third day, before dismantling everything, to experiment a lot more in this huge space and got some interesting data.
What did we learn?
Initially we had problems with positioning, we got outliers and lost tracking sometimes. Finally we managed to trace the problems to the outlier filter. The filter was written a long time ago and the current implementation was optimized for 8 anchors in a smaller space, which did not really work in this setup. After some tweaking the problem was solved, but we need to improve the filter for generic support of different system setups in the future.
Another problem that was observed is that the Z-estimate tends to get an offset that “sticks” and it is not corrected over time. We do not really understand this and will require more investigations.
The outlier filer was the only major problem that we had to solve, otherwise the Loco system mainly performed as expected and we are very happy with the result! The changes in the firmware is available in this, slightly hackish branch.
We also spent some time testing maximum velocities. For the horizontal velocities the Crazyflies started loosing positioning over 3 m/s. They could probably go much faster but the outlier filter started having problems at higher speeds. Also the overshoot became larger the faster we flew which most likely could be solved with better controller tuning. For the vertical velocity 3 m/s was also the maximum, limited by the deceleration when coming downwards. Some improvements can be made here.
Conclusion is that many things works really well but there are still some optimizations and improvements that could be made to make it even more robust and accurate.
The video
But, enough talking, here is the never-seen-before New Year’s Eve video
And if you’re curious to see behind the scenes
Thanks to CollMot for their presence and valuable expertise, and InDiscourse for arranging the video!
And with the final blogpost of 2022 and this amazing video, it’s time to wish you a nice New Year’s Eve and a happy beginning of 2023!
