Bitcraze

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!

Santa is soon to be knocking on the door, hopefully with one or two exciting toys (with blinking LEDs) for us geeky people! There will not be a Christmas video in the Bitcraze gift this year, instead we’re wrapping up a new release that we hope will add to the Christmas fun!

We have been working on a secret project though and there might be a video for next week’s blog post showing what we have been up to…

The 2022.12 release

We are happy to announce that a new official release is out, 2022.12! We have mainly fixed bugs and stability issues but also added some new features, please see details below.

Crazyflie STM firmware (2022.12)

One of the main events in this release is that the Flapper Nimble+ has got official support with the flapper platform, it can now be flashed through the client like any other member of the Crazyflie family. A new controller, based on work by Brescianini has been added. The Kalman estimator and Lighthouse system have been tweaked to work better with the increased data volumes generated with 2+ base stations. Some improvements for brushless motors have been added. Finally there have been some general bug and stability fixes, including improvements for flashing of the AI-deck.

Please see the release notes for a list of all changes.

Crazyflie NRF firmware (2022.12)

The NRF firmware release mainly contains changes to support the new STM firmware.

Please see the release notes for a list of all changes.

Crazyflie lib python (0.1.21)

A blocking method has been added to upload trajectories to the high level commander, the various Uploader classes in the examples are not needed anymore. Stability and bug fixes related to deck flashing.

Please see the release notes for a list of all changes.

Crazyflie python Client (2022.12)

A button has been added in the console log tab to get statistics about persistent storage in the Crazyflie. The final traces of Windows and Mac builds have been cleaned out and some stability and bug fixes have been applied.

Please see the release notes for a list of all changes.

This fall is full of exciting events for us, and none are more excitedly expected than our visit to Japan. Yes, the whole company (6 people) are travelling to Kyoto for at least a week – but not for sightseeing (well, not only). Here is what we have planned:

ROSCon

As per tradition, ROSCon is held shortly before IROS. So, on the 19 to 21 October, Kimberly will be here to represent us along the ROS community. She will even have a presentation about the latest ROS2 integrations in collaboration with the maintainers of Crazyswarm2. It’s on October 21st, 16.50 local time so if you’re there make sure to hear her talk !

IROS

From the 21st to the 27th of October, IROS will be held at the Kyoto International Conference Center. it’s one of largest robotics conference worldwide, with almost 1750 papers presented. As the first in-person session of the conference since the beginning of the Covid pandemic, we had to be there. We will man the booth during the whole conference, with the demo our intern Marios has worked on a lot. And since it’s been a long time since we’ve been able to gather and talk together, we thought it would be great to have an official meetup at IROS for those interested.

So, please note this official invitation to Bitcraze’s tech meetup at IROS! If you’re at IROS and want to meet us together with other Crazyflie users, then let’s get together on Monday 24th of October at 16.00 at our booth 59. It’s the perfect occasion to (re)connect, to get the latest news about Bitcraze, to talk about development, share what you’ve been doing and even possibly hack together! Be sure to say hi if you’re there. We will try to make it something similar to a Swedish fika, with some sweets and coffee, but we can’t promise that there will be kanelbullar.

IROS Safe Robot Learning Competition

And this year, we’re happy to announce that there will be a Crazyflie competition during IROS. The goal is to develop safe learning-based algorithms that can cope with uncertainties not known at design time. Our friends at Dynamic Systems Lab are organizing this competition with two simulated phase, and one experimental phase at IROS… And the experiment is a remote access to the Flight Arena at the University of Toronto Institute for Aerospace Studies in Toronto, Canada via high-speed internet connections. You don’t need to be present at IROS to participate, but if you wish to do so, beware, the registration for the competition ends on October 12th. We’re really curious and excited to see what this competition is going to show!

What about Bitcraze during that week?

But, if everybody is in Japan, what about Bitcraze’s regular activities ? You may be wondering. Well, no worries. Even though we’re going to be half a world away, the business is going to follow us. Of course, some of us are going to take that opportunity to take some vacations and visit this beautiful country, so during IROS’ week and the week after, the company will run a little bit more slowly than usual. We won’t be as reactive as usual on emails and discussions, but we will still monitor our emails and ship some orders.

Are you planning to visit IROS or ROSCon ? Is there anything in particular in the schedule that you don’t want to miss ? Don’t hesitate to tell us if you want to join the meetup !

After a period of bitcrazer-vacations, we are now all back at work. The summer here in Sweden has generally been great. Some of us stayed here to keep the company afloat, and some just stayed afloat on lakes or the sea. The majority vacationed inside of Sweden, but some (could you guess who?) have visited France, Italy, or Greece. We’ve been lucky with a mostly warm and sunny weather, perfect for bathing and grilling. And even though it’s nice to enjoy real summer, it’s still worrying sign though, as Europe is experiencing what could be the worst drought in 500 years.

Crazyflie 2.1 back in stock

What is also back is the Crazyflie 2.1, but back in stock, yay! After almost two weeks without any drones available for sale, we received a new batch of our quadcopter today. It should now be available in the shop, just in time for when school starts!

We got some indications the component shortage are slowly moving in the right direction so hopefully it will get easier to keep things in stock in the future. We are keeping our fingers crossed.

Bolt 1.1 ESC cable red/black switched

Unfortunately we recently found out that there has been a manufacturing error with the ESC cables that come with the Bolt 1.1. The black and red cables have been switched. Please see the image below.

With the black and red cables switched this will result in powering your ESCs with reversed polarity. This will most likely burn the MOSFET on the Bolt that controls the power to the ESC, which is the weakest link. This because the MOSFET body diodes on the ESC will conduct and make the whole ESC a short circuit. In many setups, e.g using 4in1 ESC these cables are not used though and will not cause a problem.

Switching the cables back is quite easy to do. Use a needle, tweezer or e.g. small screwdriver to open the plastic lock so the cable can be pulled out. Switch the black and red and you are done. You can double check that the colors are correct by comparing it with the Bolt 1.1 board. The plus and minus should match with the red and black as per the image below:

We are currently working with the manufacturer to get correct cables. If you got a Bolt 1.1 (anytime between June and August 2022) we can of course ship you correct cables once they are ready or give you support if you got problems with the control board. If so, please send us an email to support@bitcraze.io. Sorry for this inconvenience!

We’re now in the middle of summer, and even though we’re not affected by the heat much here in Sweden, we’re still in a slower pace as usual, since a lot of us are not at the office. Sales, packing, support and general maintenance takes up a lot of our time for those that are left at the office. We also usually take the summer time to clear out lingering issues and focus on some projects that we can tackle alone.

This summer though will be mostly used for preparation of a very busy autumn. As the Covid situation seems to normalize around the world, conferences onsite are restarting, and we plan to take advantage of this ! Here is what is planned:

IMAV – Delft, 12 to 16 September.

The 13th edition of the International Micro Air Vehicle Conference will be held in Delft, in the Netherlands. We’ve been collaborating for a long time with the MAVLab in Delft, so we’re really happy to be one of the sponsors for this conference. For the occasion, there is a nano AI competition that we’re really excited to see. With the AI bundle, the goal is to fly as fast as possible through an obstacle course.

We’ve been working a lot with the AI deck this past year, so this competition is the perfect occasion for us to see it in action. Kimberly has also developed a simulator that will be used for this competition.

ROSCon – Kyoto, 19 to 21 october

ROSCon is a conference dedicated to the entire ROS community, traditionally held right before IROS. Kimberly will be our proud represent there, as she will have a talk about ROS2 and the Crazyflie. For the occasion, she will showcase the latest ROS2 integrations in collaboration with the maintainers of Crazyswarm2.

Last time a Crazyflie was present at ROSCon was in 2015, where Wolfgang Hönig had a lightning talk. A lot has changed since that time, and we’re hoping to increase the presence of (tiny) aerial vehicles within the ROS community, especially nanocopters like the Crazyflie.

IROS – Kyoto, 23 to 27 october

IROS is one of the largest robotics conferences worldwide, and after an online edition last year, this 35th instance promises to be full of exciting things!

As it’s quite huge, and for a quite delayed 10th Bitcraze’s anniversary, the whole company plans to get to this conference. Not only for the chance to discover Japan, that most of us haven’t visited, but also because it feels important to have a significant presence in this conference, which promises a lot of opportunities. That would mean a week without anyone at the Swedish office, but you know where to find us if you would like to talk to us ;).

For the occasion, our intern Marios is working on revamping the autonomous swarm demo. Because of the pandemic, it’s been a while since we actually used it for a whole day of flying, and he’s actively working on making it completely autonomous by implementing the peer to peer protocol.

Logistics

As you can see, those exciting 3 conferences almost back-to-back promise a busy autumn here at Bitcraze. There’s a lot to prepare ahead of time, like marketing materials, demo setups, visas problems and hotel bookings. And there will be a lot to talk about, during and after. The pandemics have delayed a lot of our in-person meetings, and it will feel really good to finally get to meet up in the real world with users – old and new. If you have the opportunity, don’t hesitate to come by our booths on those conferences and say hello in person!

This week, we welcome Airi Lampinen from Stockholm University, to talk about the Crazyflie competition she’s organizing in Stockholm.

Welcome to our one-of-a-kind hackathon with Bitcraze’s Crazyflie in Stockholm, Sweden, on June 15-17, 2022! If you are curious about how technology and humans may play together, enthusiastic about the Crazyflie, or eager to learn how to use the Crazyflie, this event is for you.

Image credit: Paul Bechat, ETH Zurich

What, where, when? The Inaugural Challenge at the Digital Futures Drone Arena takes place on June 15-17, 2022 at KTH’s Reactor Hall – a dismantled nuclear reactor hall – which – especially if you haven’t been to this cool space before – makes attending the event worthwhile in its own right. In 2016, the reactor hall was used to film the music video for Alan Walker’s song Faded (Restrung).

Who can join? Anyone irrespective of age, profession and past experience with drones is welcome to participate. We welcome up to 10 teams of 2-4 people. We provide all the necessary drone hardware to the participants. We use the Crazyflie 2.1 and the Lighthouse positioning system. All that a team needs to bring along is a computer. Registration is open, with a final deadline on June 5 – we encourage those interested to sign up as soon as possible to secure their spot!

Program & prizes? On the first day of the hackathon, we will run short tutorials for those with no or little previous drone experience. The teams will then have access to the Reactor Hall to work on the challenge and conduct trial runs with their drone – we offer long hours but each team is free to choose how much they want to work. (The goal here is to have a good time!) The competition itself takes place on the third and final day. We’ve got exciting prizes for the most successful teams!

Read more about the challenge, the prizes, and how to sign up on our website: http://www.dronearena.info/

The event is organized as a part of the Digital Futures demonstrator project Digital Futures Drone Arena led by Luca Mottola from RISE and Airi Lampinen from Stockholm University.

Bitcraze Announcements

We have also some Bitcraze news to share with you:

Last wednesday, we had our very first mini BAM, and it led to 2 hours of interesting talks and exciting discissions ! If you’ve missed it, you can find the recordings in your Youtube Channel: here for Flapper Drones’ presentation, and here for Collmot‘s talk. We plan on having at least one another mini BAM before the end of the year, so stay tuned if you’re interested in those events.

Finally, as I talked about in this blogpost, we are looking for a new team mate to add to the Bitcraze crew. You’re interested? Check out our jobs page if you want to learn more !

Since the pandemic, having a close relationship with our contributors, partners, distributors and generally speaking, users, have been a challenge. We tried to keep in touch as much as possible, by organizing our own conference, visiting labs in Europe, or asking for feedback.

Now that it seems the situation has gone back to almost normal (and I’m crossing all my fingers as I’m writing that, which makes typing difficult), we have exciting plans for the coming months for getting closer to the community. Here are some of the things we are cooking up:

Mini BAM

The closest one is actually next week ! We are hosting a short webinar where 2 of our close collaborators will present what they’ve been working on. Matěj Karásek from Flapper Drones will talk to us about his Bolt-based drone, that is set up with flapping wings. We got to try it out in our lab last week, and it looked amazing: we’re excited you’re getting a look too!

Matej will be followed by Gábor Vásárhelyi from Collmot that will introduce us to Skybrush, its platform for any kind of swarm/fleet/multi-UAV mission control.

We’re really grateful that Flapper Drones and Collmot will join us for our very first Mini Bam to talk about drones in show! Here are the details:

It starts at 15.00 CEST on May 18th.

If you’re interested in joining, please fill out this form, or contact us at contact@bitcraze.io.
You’ll get an invitation to join the webinar.

https://docs.google.com/forms/d/e/1FAIpQLSfTGN3nHO_7fahSNbZPYJEkH8jgrRrhQV2ky4Q6OS9GLPeHNw/viewform

IROS 2022

After 2 years of online or hybrid conferences, we’re really excited to join the next one. And it’s a big one: IROS 2022, which will be held 23-27 october in Kyoto, Japan. We’re actually so excited about it that the whole company should be joining, if logistics and Corona let us. The situation in Japan is still uncertain, the country being still closed for tourism, but we are optimistic and hope for a week full of conference, meeting new people, and of course discovering a beautiful city all together. We’re planning on having a booth there, so if you plan also on visiting IROS, be sure to pass by and say hello !

We’re hiring

Of course, all of those plans take time… And we’re a little bit short on that, since (as I maybe mentioned before) we’re a little short handed right now. With only 6 people at Bitcraze, we’re getting frustrated: we have many projects, and too little time to work on them ! That’s why we have begun actively looking for a new Bitcrazer to add to our ranks. A job offer should be posted soon on our page: if you’re interested, keep an eye out for this, and be sure to let us know if you fill the profile (or someone who does!). We know it will be a long process to find the right fit for us, but we’re hopefully we will discover the person that will help us achieving all those plans – and even more!

I know a lot of you will be too distracted by chocolate to read this post, so I will make it short.

I am, too, a little distracted by sugar

As I mentioned earlier, we’re a little under-staffed right now. Jonas left us for new adventures, and Arnaud is enjoying some time with his baby (here in Sweden parental leave is thankfully long for dads too). On top of that, Kimberly was away the last two weeks to visit various labs in Europe. She will talk to you about it once she’s back, I’m sure. But with just 4 people at the office, time is a valuable resource. So what are we doing with it?

Well, a lot of that has been dedicated to the AI deck, but that’s not the only thing we’ve been working on. Recently, we had the visit of one expert on dangerous goods shipment. During 2 days, we got to learn about how to properly send the batteries we have, the regulations that are involved and what we have to implement to ship them. It may sound boring… and honestly, it was not the most interesting. But we got a certification out of it, that now allows us to ship as many batteries as we want with your order ! The 2 batteries only restriction that we have on the shop should be lifted – but please be aware that if you exceed 2 batteries per Crazyflie, the shipping cost will be higher, because of the fee Fedex imposes on dangerous goods shipments.

And speaking of Fedex, there are some problems right now on their air routes. Avoiding Ukraine and dealing with some strikes for air traffic operators in Europe has not been easy on their infrastructure, and we have experienced some delays in deliveries unfortunately. It seems to go back to normal gradually, so let’s hope their usual speediness resumes soon.

We’re also working on the Mini BAMs, which is on the 18th of May and will talk about drones for aerial show. Our special guest speakers are from Collmot and Flapper Drones, make sure to answer this survey if you want to participate ! You will get more informations soon.

And if want to play around with the AI deck, you will have an interesting occasion in September. IMAV launched a competition, where the goal is to have the Crazyflie equipped with the AI deck perform vision-based obstacle avoidance at increasing speeds. Deadline for registering are Mid-May, you can find more informations here.

We are now enjoying a long Easter week-end, recharging our batteries with families (and chocolate!), hoping that the Swedish spring finally settles here. I hope you’re enjoying it too !

A lot has happened at Bitcraze over the last months, which left us quite short-staffed. Thankfully, Victor has joined us again for a while. He mainly works on finishing his thesis with us, and we all agree that having an extra person at the office feels nice – especially considering the exciting stuff he’s working on! But let’s hear it from him first:

“Hi! I’m Victor, 26 years old, and studying towards a bachelor’s degree in Computer Science and Computer Engineering at LTH. I worked at Bitcraze during the summers of 2019 and 2020 and I’m now doing my bachelor’s thesis here.
During this thesis I will make a prototype deck that combines multiple ToF solid state lidar’s (more specifically, the new VL53L5CX). While there exists the Multi-ranger deck today, this new sensor outputs a matrix of distances, which opens up new possibilities that the Multi-ranger can not. Onboard the deck, there will also be an ESP32-S3, which will collect the data from the sensors and then send it to the PC, either through the Crazyflie, or through WiFi. This is all super exciting stuff and has endless potential, so let’s see how far I will get!”

Meet Victor!

I’m sure you will hear more on his progress in the next months, so make sure to keep updated!

Stock issues

We’ve been dealing with the component shortage as good as we can, but production is still unpredictable. Sadly, it means the impact on our stock is too. . The AI deck, the Bolt and the battery chargers are unfortunately out of stock right now. We had to change slightly the Swarm bundles to adjust to the lack of chargers. We’re also low on Multi Rangers, which are expected to run out of stock next week.

All those products are expected back by mid-May, if luck is on our side. It depends on our manufacturer in China, where there is sadly a new Corona outbreak, so it’s not easy to say for sure if this estimation is accurate. We hope that production and delivery stay unimpacted. Just know that we are working on getting everything back on stock as soon as possible. If you want to stay updated on the status of one of our out-of-stock product, you can choose to be informed by mail in our webshop. Just go to the product’s page, and put your email there: you’ll be the first one to know when it’s back in stock !

You surely remember that last fall, to celebrate our 10 year anniversary, we organized a 3 days online conference on our own. We actually loved it, and you seemed to like it to. So we’ve been contemplating the possibility of having another, on a smaller format.

And after some thoughts, we are glad to announce the Mini BAMs! As the name implies, they are shorter (maximum 3 hours if the discussions get lively), with a simplified platform (to be determined yet), but still with interesting talks, and a lot to discover from speakers and the community. Each Mini BAM will be dedicated to a specific subject, with one or two guest speakers, followed by discussions.

We already have a session programmed, so let’s see what we have in store for our very first Mini BAM!

When? The 18th of May, in the afternoon (CEST)(the exact time will be determined shortly)

What ? Our focus this time is shows in the sky! You surely couldn’t have missed that drones are getting more and more involved in shows and productions. But while aerial entertainment is getting popular, its implementation is not easy. At Bitcraze, we try to accompany artists to help them create a unique experience, but it’s not our main area of expertise. that’s why we’re turning to 2 close partners for those shows in the sky. Which lead me to….

Who ? We will have two distinguished speakers with us this afternoon.

Gábor Vásárhelyi was born in Budapest, Hungary, in 1979. He received his MSc in engineering-physics from the Technical University of Budapest, Hungary, in 2003, and his PhD in technical sciences (info-bionics) from Péter Pázmány Catholic University, Hungary, in 2007. Since 2009 he is with Eötvös University, Department of Biological Physics as leader of the Robotic Lab at Tamas Vicsek’s Research Group on collective motion. Since 2015, he is the CEO of CollMot Robotics Ltd., a spinoff dedicated to multi-drone services. His research fields are connected to the collective motion and collective behavior of animals and robots (drones). He received many awards, for exemple: Junior Prima Award, category of informatics (2007), Magyary Postdoctoral Grant (2013), Bolyai János Research Scholarship (2015), ELTE Innovative Researcher Award (2021).

You may recognize Gabor as the author of this post. For this Mini BAM, he will present us with Skybrush, his very clean platform for any kind of swarm/fleet/multi-UAV mission control.

We will also be joined by Matěj Karásek.

Matěj Karásek studied mechanical engineering and holds a PhD in engineering sciences. He spent 10 years in the academia (ULB Brussels, TU Delft) researching animal flight and developing bioinspired flying robots. He is a founder of Flapper Drones, a startup company developing bird-like robots for research and entertainment applications. 

Matej will talk to us about his Bolt-based drone, that is set up with flapping wings!

You will have time to ask them questions, and be sure to stay afterwards for discussions about show drones, the Bolt, and Skybrush!

If you’re interested in joining, follow this link to pre-register:

https://forms.gle/spDpKqhrus7WrHYJ8

More informations will of course come soon, stay updated!

Batteries in the shop

And now, for something completely different: you may have noticed that it’s difficult to order batteries with us these past weeks. That’s due to a change in transport regulation for Lithium batteries. Thankfully, we got a certification last week that allows us to ship batteries without the limitations that we had to put in the shop. We’re working on getting everything up to par with the new regulations, and shipping only batteries should soon be possible. Finally, the Swarm bundles will be, for a short time, sold without any chargers as we’re out of stock for those. The prices have been regulated accordingly.