Bitcraze crazyflie 2.0 review

Technical characteristics Bitcraze Crazyflie 2.0

Dimensions, performance and capacities

The Bitcraze Crazyflie in its version 2.0 is an indoor drone that fits in the palm of the hand and weighs only 27 g, being able to lift up to 42 g. That makes it resistant to a good part of the collisions that we can subject it, and in case of a strong blow, it is designed to break first by the most affordable parts: the engine mount (4 cost $ 5 and the drone comes with one of replacement).

The IMU inertia measurement sensor with 10 degrees of freedom, which correspond to the accelerometer (x3), gyroscope (x3), magnetometer (x3) and a high precision barometer (x1). For this drone, the quality of the measurements that the IMU takes is essential, since all the possibilities offered by this drone will pretend to control it in space. Its positive results can be seen in research projects that use it, where sensor fusion controls it quite acceptably.

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Nor does it repair processing power, integrating two Cortex modules, M4 for the main application and M0 for radio and power management. More than enough.

Connectivity

As for wireless connectivity, you can use BLE or long range low latency radio. Thanks to this, you can communicate through the Android and iOS client, or through the Crazyradio PA (not included with the Crazyflie) with the PC client.

The main physical connection is the microUSB port for charging and flashing the firmware, which can also be done by the JTAG. Of course it has two Vcc and GND connections for the battery, which is between the expansion pins. The expansion port allows to add boards to the Bitcraze Crazyflie with which the functionalities are extended. Some examples are the official LED ring, wireless charger, extension to a larger frame and its indoor location system. It should be noted that the last two are in early access, so even having final hardware, the software is green. More expansions for development are the moles (prototyping) and breakout to attach it to our board without soldering.

Development of automatic control and robotic systems

I only know ROS at the moment, but I know that Crazyflie is integrated in other platforms and software environments. For those who do not know ROS, it is an Operating System for Robotics in which our code runs as different nodes, which hang and read data in topics. To give my example, in my system an image capture node hangs it in a topic (/ camera / image_rect), which reads the image recognition node of cob_fiducials, processes and hangs the position in another topic, which my own software shells and hangs for the Crazyflie's position PID controller.

I highly recommend starting to use the software with the Crazyflie, and the Crazyflie with the software. It is ideal both for the amateur with a room with a little free space, and for universities, laboratories and workshops. It is perfect for small projects, and these can be built on top of each other. In my department, for example, someone prepares the software to take images in the most accurate way and prepares it with documentation so that the next student can use this physical and computer assembly to do their automatic control, and the one that comes after can use that control to follow paths that are given to the drone.

Before finishing, it should be noted that the Crazyflie sensing can be done both only with the IMU itself, as with generic cameras (my case) or more or less expensive and complex detection systems, and mixing several of these methods.

Final words and conclusion about Bitcraze Crazyflie

After having used it, and comparing it with the Parrot AR.Drone2.0 that a companion also uses in ROS (despite having proprietary software blocks that we will not be able to modify or know about), this one presents features clearly superior to Crazyflie 2.0. The AR.Drone is more convenient for recreational flight, but although it can be used indoors, it needs considerably more free space in the room / laboratory and that can be cumbersome.

It should be noted that we will need a desktop or laptop PC to execute our projects in both, so in development projects sometimes it will not be practical to take them to the field.

However, I highly recommend Crazyflie 2.0 to anyone who wants to start or continue playing computer science and robotics with something as fun as a drone, or to teach others. Systems, programming, control theories and aerodynamics, all that is at our mercy in the palm of our hand.

ADVANTAGE	DISADVANTAGES
+ SOFTWARE INTEGRATION	- PRICE.
+ MAINTAINED SOFTWARE	- DOES NOT COME WITH CRAZYRADIO PA, NECESSARY
+ FORUM	- LOW BATTERY (7 ′)
+ SIZE AND USABILITY	- DOES NOT COME WITH REPLACEMENT BATTERY
+ WIDE ACCESSORY CATALOG	- MANUAL FLIGHT IMPROVABLE BY THE PRICE RANGE