IMU availability and calibration

Phew! Yesterday evening/night we packed most of the IMU Brick orders, the shipment email should have already been send too.

We are sorry for the long delay! In the future we will make a product that is produced in big numbers for the first time only avaiable in the shop after we have it here and tested. The gyroscope/accelerometer/magnetometer ICs use a Quad Flat No Leads Package (QFN). This means that the pads are below the chip. It is not possible to see solder straps via a visual inspection. For this reason we had problems that lead to more delays (the IMU Bricks had to be X-rayed).

All IMU Brick orders that don’t include a Dual Relay Bricklet should be marked as shipped. We did run short of them unexpectedly yesterday. But that is no big problem, a big batch of new ones are already on there way und they should arrive in the evening today.

With the automatic calibration we had problems to subtract out the magnetic field of the servo motors (this is definitely possible und we will do that in the future). To assure that there aren’t more delays we did calibrate the magnetometers of the first 250 IMUs by hand. The precision did likely suffer, but the magnetometer has to be newly calibrated in most use cases anyway (if the IMU i used near a motor or similar).

And now the announced video:

The hardware is completely based on Sebastian O.H. Madgwick published “gimbal components”. The servo motors and brackets are from servo city and the controlling is of course done with a Servo Brick. The code for the calibration can be found in the IMU Brick git.

Chibi or no Chibi, that is the question

As many of you have probably already read in the forum, we intend to not sell the Chibi Extension anymore.

The reasons: The frequency band that we are able to use in Germany with Chibi has a range from 868.0 to 868.6Mhz (We still sell mostly in Germany). The Bandwidth of 0.6Mhz is so small, that only one channel can be used.

Now it seems that there are radio thermostats and similar devices that use the same frequency and they leave absolutely no space for the Chibi Extension. It seems that they are spamming values like the temperature and if the receiver receives every 100th or 1000th message the system works. With our system we require every message to go through. So we resend until we get an ACK.

This means that for approximately 5-10% of our customer the Chibi Extensions doesn’t work sufficiently. To this number you have to add the people that just don’t report the problems. It seems that either the first enumerate message doesn’t go trough and the Chibi slaves are not found or it only works with very small distances.

We already did invest lots of time but we simply weren’t able to find a solution for this problem. Since we currently have more TODOs than we are able to cope with (RS485, IMU calibration, open orders etc), we decided to remove the Chibi Extension from our product line for now.

It seems that there are nevertheless lots of customers that like the Chibi Extension (,462.0.html). We will, after the RS485 Extension is released, give the highest priority on our TODO list to the WIFI Extension. With the WIFI Extension it will be possible to communicate with a stack of Bricks directly over WIFI, either in you home network over an access point or directly via ad hoc mode. Since the connection is done directly over TCP/IP there is no need for the Brick Daemon. This means that it is possible to e.g. control a robot directly from a smartphone without any PC connection! A first prototype and the basics of the software do exist already:

The only big advantage of the Chibi Extension compared to the WIFI Extension is the range. With a normal Antenna comparable distances are not possible with WIFI. We did order some directional antennas and will put the best of them in our shop when the WIFI Extension is available.

As a compromise we thought of the following: After we released the WIFI Extension we will make another survey about Chibi. If there is still a high interest, we will first try to make our Chibi firmware more stable with the help of external expertise. If that doesn’t help with the problems we will search for another frequency that allows for comparable distances and develop another wireless extension!

PS: The IMU calibration is running at full blast. We will probably make a video of the automated calibration process at the weekend, of course we used Tinkerforge Hardware for that :-)!

Ruby bindings ready

The Ruby bindings are now ready to use!

If you find bugs, please report them in the generator git:

The next bindings we are releasing will probably be Delphi bindings.

Shippment now with DHL

As of now we are shipping all Packages inside of Germany with DHL Premium. We were able to negotiate a price with DHL that is below the shipping cost from before (shipment with registered mail): The shipping cost is now 4.10€ instead of 4.25€ inside of Germany.

Since we don’t have high enough shipment quantities outside of Germany currently, we are shipping with the non-discounted DHL Premium prices outside of Germany. Especially outside of the EU this can be quite expensive (20-45€), so we offer shipping with registered mail there additionally.

It should be mentioned that DHL Premium shipments (compared to registered mails) are insured and have full worldwide tracking!

Furthermore we removed the free shipping starting from 65€. Now Customers with smaller orders don’t have to pay for the shipment of customers with big orders. Our experience has shown that big orderes are often so big, that the shipping cost itself wouldn’t really matter anyway.

PHP bindings ready

The PHP bindings are now ready to use!

If you find bugs, please report them in the generator git:

The next bindings we are releasing will be Ruby bindings.