Crazyflie 2.1 Brushless

Specifications

Features

• Fully compatible with the Crazyflie 2.X ecosystem
• Multiple position technology support
• Easy to assemble and no soldering required
• Supports expansion decks with automatic detection
• Wireless firmware updates
• On-board charging via standard uUSB or contact pads
• Open source software with extensive library support
• Swarm and ROS support
• Low latency radio with peer-two-peer functionality.
• Low noise flight

Mechanical specifications

• Takeoff weight with legs: 34g
• Takeoff weight with guards: 37g
• Frame size: 100m (diagonal motor center to motor center)

Onboard microcontrollers

• STM32F405 main application MCU (Cortex-M4, 168MHz, 192kb SRAM, 1Mb flash)
• nRF51822 radio and power management MCU (Cortex-M0, 32Mhz, 16kb SRAM, 128kb flash)
• micro-USB connector
• On-board LiPo charger with 100mA, 500mA and 980mA modes available
• Full speed USB device interface
• Partial USB OTG capability (USB OTG present but no 5V output)
• 8KB EEPROM

IMU specification

• 3 axis accelerometer / gyroscope (BMI088)
• High precision pressure sensor (BMP388)

Flight specifications

• 4 x 08028-10000KV high-quality motors generating up to 30 grams thrust each
• 4 x integrated 1-cell 5A ESCs running BLHeli_S/Bluejay
• Custom-designed and optimized 55mm propellers with 35mm pitch
• Flight time with stock battery: 10 minutes
• Charging time with stock battery: 60 minutes
• Max recommended stock payload weight: 40 g

Radio specification

• 2.4GHz ISM band radio
• Increased range with 20 dBm radio amplifier, tested to > 1 km range LOS with Crazyradio PA (environmentally dependent)
• Bluetooth Low Energy support
• Dual antenna support with both on board chip antenna and U.FL connector

• Datasheet
• Schematics
• Expansion Decks

Usage

We designed the Crazyflie 2.1 Brushless to be as flexible as possible, offering a wide range of features and easily customizable firmware. It includes the same flexible expansion interface found across our entire drone lineup, allowing users to easily integrate ready-made expansion decks or access buses like UART, I2C, SPI, PWM, analog in/out, and GPIO.

We are constantly improving the firmware, software, and documentation. At the same time, we are exploring new, creative ways of using the system. Additionally, we design new expansion decks that bring added functionality, expanding the possibilities and growing the Crazyflie ecosystem. The platform also supports wireless firmware updates via radio and Bluetooth LE, making it easy to update whenever a new version is released.

Getting started

Go to the crazyflie 2.1 Brushless getting started tutorial to assemble your Crazyflie, update its firmware and fly it. Also take a look at our System overview to learn more about the Crazyflie’s ecosystem of positioning systems, clients and of course the Crazyflie itself with its expansion decks.

Safety instructions

You are responsible for handling the drone and its components. It is your responsibility to make sure you understand how your drone works and that it is in good working condition before flight. Using a drone in a reckless and negligent manner could cause damage or bodily harm, resulting in lawsuits, fines and jail time.

Stick to these guidelines ensure maximum safety:

• You should check your drone before and after each flight to make sure it’s working properly and there isn’t any damage.
• Don’t make contact with a spinning propeller. A spinning propeller is hazardous if carelessly handled. Always avoid getting your fingers too close to them.
• When possible, build, test and configure your drone without its propellers attached.
• Avoid catching the drone mid-flight or while it’s landing.
• Always make sure that the path of your drone is clear to avoid any accidents.
• Use the propeller guards as much as possible

Useful links

• System overview
• Getting started with the Crazyflie 2.1 Brushless
• All other tutorials

Development

Open Source

The Crazyflie 2.1 Brushless is an open source project, with source code documented and available. Since all of our development tools are open source (except for iOS) we are allowed to redistribute them in an easy way for our users. Aside from the firmware and software projects, there are a number of community supported APIs written in Java, Ruby, C/C++, C#, Rust and Javascript.

Development

There are ample opportunities to play with the code regardless of which language you prefer. Our client API is written in Python, while there are many other client-side implementations on GitHub written in Ruby, C#, C/C++, JavaScript, Node.JS, Cylon.JS or Java. Or, why not clone our iOS repository and get into some ObjectiveC/Swift.

If you are into C and embedded systems, the main MCU STM32F405 has a lot of processor power you can use for doing experiments, making improvements and adding new features. Once you have made your modifications, simply flash the new firmware over the radio and you are ready to go. For those interested in more advanced development, there is a development adapter kit that supports an easy JTAG/SWD connection to both of the MCUs on the Crazyflie 2.1 Brushless.

The expansion decks allow you to experiment, prototype and design your own hardware.

We think that a development platform should be something more than just making the code available, therefore our software, firmware and utilities have functionality such as logging, real-time parameter setting and wireless firmware updates.

Expansion connector specification

The expansion connector is used to attach decks with additional functionality. Either official Bitcraze decks can be used or custom ones can be design using our KiCad template.

The expansion connector includes the following:

• VCC 3.0V (max 100mA)
• GND
• VCOM (unregulated VBAT or VUSB, max 1A)
• VUSB (both for input and output)
• I2C (400kHz)
• SPI
• 2 x UART
• 4 x GPIO/CS for SPI
• 1-wire bus for expansion identification
• 2 x GPIO connected to nRF51

Please note the following:

• The Crazyflie 2.1 is a 3.0V system, meaning a high output will be 3.0V but still compatible with a 3.3V system.
• All IO pins are 5V tolerant except PA5 and the NRF51 pins
• The NRF51 pins can be multiplexed with any of the available NRF51 peripheral.
• The STM32F405RG pins can be multiplexed with more functions.

Expansion connector multiplexing

• Development overview
• Repository overview
• Github Page