Category: Crazyflie

Back in November when we got the pre-series we shot an assembly video showing how to assemble a Crazyflie kit. We shot it in Tobias shed in his back garden where it was about 10*C, that’s why Marcus is wearing a winter jacket. It was also pretty late and it’s the 7th Crazyflie in a row that we have tested and assembled, so we where pretty tired. We are not trying to find excuses but it might not have been our best work. For example the words “the best way” is frequently used, and due to our Swedish heritage, “one good way” might have been more appropriate, but that day we where just feeling confident :-).

If you have ~8 minutes to spare have a look at the video, so you know what to expect in terms of assembly, when you pretty soon will be able to pre-order the kit.

We’re still busy with administrative stuff and preparing everything for release so sorry for the lack of tech posts. Hopefully there will be more time for those later :-)

But we did spend one night this week trying out something that we have talked about forever: Using OpenCV to auto-pilot the Crazyflie. For controlling the Crazyflie from a Python scripts it’s just a couple of lines and then you are ready to go. Add some object tracking to that and you can make an autonomous Crazyflie…or you could make a crashing one like the video below… The video is shot using a Playstation Eye lying on the floor. The camera has good potential for tracking since it’s low resolution, cheap and can do up to 120 fps. The plan is to use the size of the detection to control the thrust and the center of it to control the roll and pitch.

Unfortunately the latency was too large for doing a control loop for roll/pitch/thrust so it crashes. But hopefully in the future we, or someone in the community, will have some more time to spend on this. We think that it definitely has potential!

Part of this test was also to have another project where we use the Crazyflie Python API to make sure that it can easily be dropped into other projects.


We are back from vacation and now it’s full speed ahead! As you might have read during the holidays there hasn’t been that much going on, we have been resting up for a busy spring.

During the upcoming week we will be writing product descriptions for the Crazyflie Kit, Crazyradio and spare parts kit that will be published for the pre-order at Seeedstudio. We are also working on cleaning up the final parts of the code and cutting an assembly video for the hardware.

So the next couple of weeks will be busy and exciting so make sure to stay tuned :-)

So a year ago, on the 3rd of January 2012, we published the first post here on as we moved from our old site at Back then we were fairly confident that we would release the kit during the first half of 2012. But it turned out the be more work (and more problems) than what we thought. Now as the new year begins we are very confident that anyone who wants a Crazyflie will have one in their hand before the first half of 2013 has passed.

Even though we haven’t made much progress the last two weeks it’s now a matter of fixing the details like packaging, what parts should be in the spare kit and so on. We feel that the hardware and the current state of the software is good enough for release when the kit is released (after some cleaning up). There’s still a long list of stuff that we would like to do but don’t really have the time for. So if you get a Crazyflie Kit and want to contribute there’s a lot of fun stuff still left that we need help with.

Next week is our first Monday meeting after the holidays and then it’s full throttle forward.

Happy new year and thanks for supporting us!

Even though it’s Christmas Eve we managed to sneak away from the celebrations to post the regular Monday post. Unfortunately there’s not much progress to report this week, but we are continuing the planning for the release of the Crazyflie Dev Kit. More and more stuff is being sorted and soon all the details will be in place. As soon as we have a timeplan we feel that we can commit to we will release more information.

Finally we want to wish everyone a Merry Christmas!!

A combination of Christmas preparation, overtime and water leakage took most of the time during the last week so not much progress was done :-(

So what’s the current status in the project? Well, we are still discussing with Seeedstudio on how to start up but most of the things are now in place. We are continuously working on the software/firmware and wiki when we have spare time. Also since we don’t really know how many kits we will sell we are aiming at having a two week pre-order phase before the production of the kits begin.

After one week of flying the new copters we have to say that they are preforming very well. We’ve done a lot of crashes but only had one incident with a bent axis on one of the motors which we fixed by replacing the motor.

We have noticed that using some radio channels in combination with some link speeds causes too much packet drops when the motors are powered. It’s almost certainly the PWM that causes ripples on the power supply and that effects the radio transmission. It was by chance we saw this and changing the channel or speed works around the problem.

Currently we are working with Seeedstudio to sort out the details for starting up but we don’t have an estimate for when it will happen yet. But one thing is for sure, we will go with the rapid-prototype mounts for the first DIY kit. We are still working on the details for the molded motor mounts but since there’s a lot of leadtimes for this it would delay the kit with months and we really don’t want that. Since after the summer we have been using the same design for the rapid-prototype motor mounts and we have only had 2 that has broken.

The plan is to package 1 spare motor, 1 spare motor mount and 4 spare propellers with the kit. There will also be extra spare parts available for purchase.

On Wednesday we assembled and tested all of the kits in the pre-series. We ran though the production tests, that will be used once the kits are produced, as verification. Since we can’t test that they really can fly the test isn’t covering everything but it checks most of the components. One of the units had a solder-bridge between two of the MPU-6050 pins and our tests showed that the unit was faulty. We are glad our tests caught the problem and removing the short fixed it.

The assembly doesn’t take too long and once you have done a few it’s fairly quick. We timed the last one we assembled and it was finished in just under 10 minutes (including fixing errors that were made :-) ). And that time was done by the worst solderer of us! As long as you are a bit steady on you hand it should be ok. It was a really great feeling unpacking, assembling, testing and then directly flying them! We numbered all the units and will track them if there’s any problems. So during the next weeks we will be flying a lot :-). We cross our fingers that they will hold up to what we expect.

The change we did where, connecting the motors directly to the battery and not through the power management chip, turned out great and we could feel the 8% increased power difference (it might have been some placebo effect but it just feels great).

To sum it all up it was a great night and we are really happy with the results! We remember in the beginning when we had to be in a pretty big room to be able to fly the Crazyflie at all and now it’s so stable you can (if you are brave enough) hover it 10 cm in front of your face and then push the throttle and it swishes away!

As for the project progress we are now discussing with Seeedstudio on how to carry on and we are trying to sort out the motor mount problem and some smaller issues.

We’ve also spent some time creating a new page on the wiki describing the hardware. It’s still a work in progress, but there’s a lot of information. We will continue updating the wiki whenever there is time.

Head over to our Picasa albums for more pictures.


Finally our yearning has come to an end, the Crazyflie kit pre-series did arrive from Seeedstudio today! We have not had time to do any extensive testing but so far so good, yay! We did however have time to program and assemble one and it flies really well. It feels like the change we did to route the motor supply directly to the battery and not trough the power management circuit made a difference. The acceleration punch when maxing out the throttle feels stronger. We have uploaded some pictures of the received package. What is still not included in this package are the motor mounts which we ordered separately from Shapeways. The motor mount is one of the last things to sort out before the kit can be ready. We are working on a moulded version which will be much cheaper in bigger quantities but it takes way more time then we expected. We might go with rapid prototyped mounts instead to make it available sooner.

The upcoming week is going to be very interesting as the testing will determine if we can go to the next step!

Since the very beginning of the project we have been maintaining a wiki. At first mostly for internal communication and documentation but more recently we have been focusing on making an easily accessible documentation for the Crazyflie kit.

We now think the wiki is good enough to be released. It is still a “work in progress” but most of the basics are there and it will be updated as we go along. On the wiki we plan to have all information regarding the Crazyflie and other projects. We also intend to complement the wiki with a forum which will be the next step.

The wiki is located at and can also be accessed via the wiki link in the navigation bar.