Alexander's Posts (2)

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Look what came out of my reflow oven!

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Hi guys,

 

Here I want to show you my new autopilot hardware which I worked on the past weeks.

The layout and the connections of the boards are chosen for my own convenience.

So airspeed sensor, receiver input, GPS, LEDs and I2C connections are at the front of the autopilot.

Servo output, serial ports, ADC and open drain outputs are at the back.

 

I also belief in the modularity, having two boards it is easy to replace the main board in the future when I need more performance and using the "expensive" IMU board again. It's still a small system with a height of 12mm and board dimensions of 62mm x 40mm, the weight is 35grams (mainly due to the stiff 1.6mm thick boards).

 

It's almost APM code compatible, only difference is the gyro+acc. sensor connected directly via SPI and the airspeed sensor which is connected to I2C via a one channel 16bit ADC.

 

It has all sensor "needed" on the IMU board, which are:

Compass:   HMC5883L

3 axis Gyro+Acc.: SD746 (or MPU6000 if it is coming available and prove to be better that the SD746)

Baro: BMP085

Airspeed: MPXV7002 (via ADS1100 16bit ADC)

Three open drain outputs

Three ADC inputs

Three Serial ports

I2C port (5volt)

GPS (Serial port, EM406 pinout)

Status LEDs

 

Main board:

 

ATmega2560

ATmega328

TRACO regulator (max 36 volt input to 5volt output)

Eight channel receiver input at the front of the board

Ten channel servo output at the back of the board

 

Below are some picture of my work, now I have to test and do......some more testing :-)

Please let me know what you think of this solution......

 

Wish you all the best,

 

Alexander

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Preview of my wireless modem development



Here is a preview of my long range wireless modem.

It's based on a Radiocrafts 868Mhz module (RC1180HP) with 450mW RF output power and good receiver sensitivity.

I'm going to use this for modem telemetry and antenna tracking, one in groundstation and one in the airframe


It has the following features:

1x LCD 102x46dots

4x Buttons

1x MicroSD slot

3x analog to digital inputs

1x I2C

1x SPI (if LCD is not used)

1x RS232 (TTL)

2x Timer outputs (used to connect a 4017 to drive servos)

4.5 to 32volt DC input

Dimensions are 44mm x 55mm x 5mm


More info will be added later.....and yes it will be open-source, I will share all design info if you want....

Edit:

Here you can find the schematics: RC1180HP-Modem.pdf



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