Category: Random stuff

We just received the first 10 sample boards from the production at Seeedstudio :-D

DSC_0210e

So far we got time to test only two boards and they are working. We have finalized the firmware, bootloader and production scripts so now it has really started :-)

Nothing new exiting about the production, it is still going as planned :-). Meanwhile we are focusing on stabilizing the Crazyflie firmware and its side projects.

This weekend we fixed a bug related to the memory allocation, which we have had a while now and that we never had time to track down. It kind of forced us to use heavier machinery so we decided to setup eclipse for debugging FreeRTOS threads and it happened to be very useful.

Since version 0.5 OpenOCD contains a rtos-awarness mode for FreeRTOS and, when painfully configured in eclipse, this allows us to observe the stack trace and the running state of all the tasks running on Crazyflie:

eclipse-threads

This helped us to track-down the bug much quicker and will greatly help us in the future. We also found a eclipse plugin, embsysregview, that enables one to show and analyse the peripheral register values, great little plugin!

The virtual machine will be updated with the debug environment and we will try to update the Wiki with the setup procedure.

As announced on the last Monday post and as well discussed on the forum, one of the things we are working on right now is to create a virtual machine (VM) that would greatly reduce the haste of getting the running/development environment up and running. The VM will be a Linux system that can run on Windows, Linux or Mac and that will be pre-configured to work with Crazyradio and Crazyflie. We are going to post the first alpha of this virtual machine during the week using Bittorrent so if you are interested to test it stay tuned to the forum!

As for the production of the Crazyflie’s things are running according to schedule, so far so good!

Also from the VM discussion we discovered that Mike has done a great job getting the Crazyflie client to work on Mac OSX. This is going to greatly help supporting Crazyflie on OSX.

Hi, Monday again. We just passed the two most exiting weeks in Bitcraze history. As we speak we are passing the 1K Crazyflie sold which is about 5 times over our optimistic estimations. Now the pressure is on, and there is still one week of pre-order left :-).

We are continuing to update the documentation, working on Crazyflie firmware, the PC gui client and as well all emails/administrative work that takes a surprising amount of time :-). Due to popular interest the focus has been on getting the client to work on Mac OSX and getting Crazyflie to work in a standalone mode (ie. no PC) with an E-sky R/C transmitter which is compatible with our radio chip. The transmitter is almost working (still some mapping issues to work out) and the OSX proof-of-concept is on the way to work (it should work out of the box if all the python libs where 64bits).

We should probably clarify that the PS3 controller we use to control the Crazyflie is just one possible input method. Actually any input device could be used which could be translated into roll, pitch, yaw and thrust. The GUI also simplifies it as there is a configuration dialog and soon we might have our first contribution which is for the xbox controller :-)

We are continually updating the wiki and are starting to get some activity on the forum. It is the right place to go if you have questions or want to discuss about the Crazyflie.

Thanks again for supporting us, one more crazy pre-order week to go!

Who knew that it was possible to discuss product descriptions for almost a whole evening… Since the release is getting really close now we actually have finalize the product description and it turns out that we didn’t all agree on everything. One thing that’s good about being three people in this project is that we can have a lot of discussions that gives (hopefully) good results and the bad thing is that there’s a lot of discussions which takes a lot of time :-)

Another night without any flying at all, just administrative stuff… But if everything is goes according to plan the pre-order should start within the two next weeks!

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!!

Last week we received one of the new raspberry pi and we wanted to start doing something useful with it. One idea that came directly in mind was to control the copter with it. As it has 2 USB port it should be possible to use one for the gamepad and one for the Crazyradio dongle.

The Raspberry pi running Debian the operation ended up being surprisingly easy: Just apt-get install python, pygame and pyUSB and we where able to run our old script. By adding pyQT we where even able to run the GUI out of the box (it is still a bit heavy though as the GUI is not yet very optimized when receiving fast log informations). So we just made a “headless” version of the control software, launched it automatically with a udev rule when the radio is inserted and it was done!

We can power the Raspberry pi with a USB battery and we now have a small portable ground station for the Crazyflie. We have also proven that our PC software tools are easily portable to other architecture thanks to Python and all its libs. Currently the software is tested on Windows and Linux (x86 and ARM), but it should also work on MAC.

Raspberry PI controlling the Crazyflie

While we are waiting for the pre-series to arrive, which hopefully will be within 4-5 weeks, we have tested this idea we have had for a while. On the Crazyflie PCB we placed mounting holes in each corner for the possibility to add e.g. a landing gear, canopy or maybe a protective frame. The holes are about 0.9mm and plated so it is possible to solder something in it and a protective frame made of piano wire would be a good candidate.

We bought a couple of 0.8 mm thick 1m long piano wires at a nearby hobby store and got to work. On the first try we bend the wires into the shape solely by hand and it didn’t look or work well at all. We figured there must be some better way! And after searching the net we found this site explaining how to make your own DIY springs of different types. We however needed a circle with a much bigger diameter than normal springs use so it took us a while to find a tube with the right diameter to bend it around to get the right size. We found out that when bending the piano wire around a tube with the diameter of 20mm it ended up at about 55mm which was close enough to the 60mm we needed. Piano wire is a bit hard to solder but with plenty of solder flux it works well. We are pretty pleased with the result!

The piano wire frame itself weights about 3.5-4g so it is within the acceptable payload limit. The flight characteristics is changed a bit making it more controllable but less agile which is perfect for beginners. We have tested throwing it in the ground and crashing it several times and the Crazyflie just bounces so it works great. It might even be possible to go to a smaller piano wire diameter to save weight because now the frame is very stiff. Next step would be to come up with a design that could be attached/detached without soldering. It should also be cheap and easy to manufacture.

This week we decided to do our weekly meeting at the local pub. Why? We needed some beer to calm our nerves and to get some expert advice from Martin, one of our collegues, that has presented at a lot of conferances. The reason for this is that in about two weeks we are presenting the Crazyflie project at the annual Øredev developer conference in Malmo, Sweden.

The presentation will be a mix of the project history, some tech details and of course a demo (hopefully a successful one without any injuries ;-) ).

So if you are attending Oredev drop by our presentation on the 7th of November at 15:40 in the Nyan Cat room and we will do our best to give you an interesting 50 minutes.

We discovered a new key-chain video camera which is called the 808#16. It had gotten a pretty good review so we decided to give the video camera add-on hack yet another try. A while ago we tried it with a 808#14 but it didn’t work that well when we where running it directly from the Crazyflie battery. It shut down as soon as we used to much throttle and using a separate battery made it to heavy. We didn’t have to high hopes for the 808#16 either and when we discovered that the bare camera weight, no battery nor case, was about 9g we knew it would be at the maximum of what the Crazyflie could carry.  With high hopes we connected the camera directly to the Crazyflie battery terminal and gave it a try.

It worked! The camera didn’t shut down but as you can see the stability is pretty bad during take-off. Once in the air it is controllable but only barely. We haven’t tested the full flight time but it probably wont be more then 2-3 minutes. We are thinking of doing a test where we add 4 more motors “mirrored” directly underneath the existing ones to increase the payload capability. Would be nice to have that option and it should be fairly simple to do.

We are pretty impressed with the video of the 808#16 which still is very cheap. We bought the 808#16 camera with the D-lens which is a wide angle lens and that’s why the video has a bit of a fish-eye.