New Low Cost STM32F4 based PPZ UAV Autopilot In China

Paparazzi Hyper X Autopilot

1 Overview

Hyper X UAV autopilot board is based on the 100 pins STM32F407VGT6 Cortex M4 168MHz processor featuring a Floating point unit (FPU), up to 192k of RAM and 1024k of FLASH.

It is based on STM32 Discovery board and is a ultra low cost UAV autopilot board that is made by cheap electronic components/modules, which you can get easily n the Chinese market (e.g. GY-86 10DOF 8.5� in http://www.taobao.com). So it is suit for China's national conditions.

・                     STMicroelectronics STM32F4VGT6 Cortex M4 MCU, up to 168Mhz with floating point unit (FPU), 192 KB RAM, 1024 KB Flash

・                     on-board STLinkv2 with SWD header (capable of programming onboard or external MCU)

・                     on-board power regulator for the MCU (3V or 5V Input)

・                     MPU6050 Gyro/Accelerometer sensor and MXR9500 Accelerometer with 16 bit ADC (Big Rotorcraft Edition).

・                     HMC5883 magnet field sensor.

・                     MS5611 high precision pressure sensor

・                     UBLOX GPS NEO 6M

・                     2 x 3.3V TTL UART (UART3, UART6, 5V tolerant)

・                     1 x I²C 5V bus (I2C2, 5V tolerant)

・                     11 x Servo PWM outputs

・                     4 x status LED (orange, green, red, blue,)

・                     2 x UART (UART3, UART6)

・                     LIS302DL MEMS 3 axis accelerometer on SPI1

・                     6 x ADC inputs (one is used for BAT voltage)

・                     1 x Spektrum input (with bind pin)

・                     8 x Radio PWM inputs

So, except for a Modem unit with the Hyper X you have all necessary sensors for full features all in one Rotorcraft or Fixedwing solution.

2 Detail Features

10 DOF IMU GY-86

Tiny, low cost 8.5�, 5V and 3.3V input (onboard voltage regulator), I2C interface.

Chinese GY-86 is a low cost and precise solution for normal aircraft with a excellent baro sensor. GY-86 (MPU6050-HMC5883-MS5611) is similar to Drotek 10DOF, but have different I2C address. The slave address of the MPU-6050 is b110100X which is 7 bits long. The LSB bit of the 7 bit address is determined by the logic level on pin AD0. When it is used in GY-86, the address of the devices should be b1101000 (pin AD0 is pull-down to GND). Because of the I2C data bytes are defined to be 8-bits long, so the I2C address of GY-86 should be defined as b11010000(0XD0)

The Measurement Specialties MS5611 is an excellent barometer/pressure sensor. The sensor can be used as I2C device. Reading the baro is not part of the IMU driver. If you want to use it for altitude estimation in the autopilot the following line needs to be added to your airframe file: <define name="USE_BARO_MS5611"/>

To see the sensors data in the log file set the SENSOR_SYNC_SEND in your airframe file. Every time new data is available it will be sent directly.

PPM Encoder

ArduPPM is a 8 channels ppm encoder firmware for the APM project, which is second generation ppm encoder code designed for APM boards. Now the ArduPPM is employed by Hyper X UAV autopilot board and is running on an Arduino Pro Mini that is a microcontroller board based on the ATmega328.

More information：https://github.com/diydrones/ardupilot/tree/master/Tools/ArduPPM

3 Pinout

4 Daughterboard

Hyper X is based on the STM32F4 Discovery and is designed for Chinese students. It is as simple as possible. The impedance matching resistors and voltage conversion chips on I2C or UART ports are omitted. In order to ensure adequate safety margin, 100ohm impedance matching resistors are added on PWM output ports, and 100nf filter capacitors are mounted at UART power ports. 1n4148 diode clamp circuits (may affect ADC’s precision) are created at ADCs 1 to 4. The ADC 5 and 6 have no diode clamp circuits and can collect small voltage signal normally.

5 Build the code

1 Unpack paparazzi.tar that is provided by me

2 copy all files in folder “Pararazzi” to ~/paparazzi (which is the same path of your paparazzi folder)

3 launch paparazzi center (cd ~/paparazzi && ./paparazzi)

4 select MYAC in A/C

5 Build and Upload

6 Enjoy

6 Firmware Flashing

FLASH_MODE=STLINK is set as default

STLINK

   with onboard STLinkV2 over SWD

   required hardware: usb to mini USB cable

   required software: st_flash and st_util from Texane