Autosteer controller.
This just just for demonstration and proof of concept. This should never ever be used on full sized machinery. You will crash and die if You do. You have been warned.
Pictures and something here.
Why Raspberry Pi? It's just somethin I had laying around.
Configure raspberry:
sudo raspi-configFrom System Options set Wireless LAN, from Interface Options enable I2C, disable login console on serial port, enable serial port hardware.
Edit /boot/firmware/config.txt
sudo nano /boot/firmware/config.txtAdd the line dtoverlay=pwm,pin=12,func=4
Save the file and reboot.
wget https://github.com/salmiac/pi-steer/releases/download/v0.1.5/pi-steer-rust
chmod +x pi-steer-rustRun it once and default settings file (settings.json) is created.
Edit file.
nano settings.jsonTo build binaries Yourself look here
Is used as standalone IMU. README.md
If GPS is connected to Raspberry Pi serial port, there is just not enough IO-pins for IMU.
| Device | pin | Pi GPIO | Pi pin | Pi pin | Pi GPIO | pin | Device |
|---|---|---|---|---|---|---|---|
| BSS138, BNO055, BNO085 VCC/PS0 | LV, VIN | 3v3 Power | 1 | 2 | 5V Power | HV, VDD | BSS138, ADS1115 |
| BSS138 (ADS1115), BNO055 | A2, SDA | I2C SDA | 3 | 4 | 5V Power | VCC, 1-A | RTY120LVNAA |
| BSS138 (ADS1115), BNO055 | A1, SCL | I2C SCL | 5 | 6 | Ground | GND, 2-B | RTY120LVNAA |
| Relay | 1 | GPIO 4 | 7 | 8 | GPIO 14 | TXD | BNO085 SCL/SCK/RX |
| BNO055 | GND | Ground | 9 | 10 | GPIO 15 | RXD | BNO085 S/MISO/TX |
| Relay | 2 | GPIO 17 | 11 | 12 | GPIO 18 | 2 | Manual (in) |
| Autosteer switch | A | GPIO 27 | 13 | 14 | Ground | GND | Relay |
| Relay | 3 | GPIO 22 | 15 | 16 | GPIO 23 | 3 | Manual (in) |
| LED:s | + | 3v3 Power | 17 | 18 | GPIO 24 | 4 | Manual (in) |
| Relay | 4 | GPIO 10 | 19 | 20 | Ground | - | Power LED |
| Relay | 5 | GPIO 9 | 21 | 22 | GPIO 25 | 5 | Manual (in) |
| Relay | 6 | GPIO 11 | 23 | 24 | GPIO 8 | 14 | Relay |
| Autosteer switch | B | Ground | 25 | 26 | GPIO 7 | 13 | Relay |
| Relay | 7 | GPIO 0 | 27 | 28 | GPIO 1 | 12 | Relay |
| Relay | 8 | GPIO 5 | 29 | 30 | Ground | GND | BSS138 |
| Relay | 9 | GPIO 6 | 31 | 32 | GPIO 12, PWM 0 | PWM | Cytron |
| Work switch | GPIO 13 | 33 | 34 | Ground | GND | Cytron | |
| Relay, manual mode | 2 | GPIO 19 | 35 | 36 | GPIO 16 | DIR | Cytron |
| Manual (in) | 1 | GPIO 26 | 37 | 38 | GPIO 20 | 11 | Relay |
| Relay mode switch | GND | Ground | 39 | 40 | GPIO 21 | 10 | Relay |
| Function | pin |
|---|---|
| Vcc 5V | 1-A |
| GND | 2-B |
| output | 3-C |
Wires connectedd to raspberry Pi via level converter
| GPIO | Pi pin number | BSS138 |
|---|---|---|
| 3v3 Power | 1 | LV |
| 5V Power | 2 | HV |
| I2C1 SDA | 3 | A1 |
| I2C1 SCL | 5 | A2 |
| Ground | 7 | GND |
| GPIO | Pi pin number | ADS1115 | BSS138 | RTY120LVNAA |
|---|---|---|---|---|
| 5V Power | 4 | VIN | 1-A | |
| SDA | B1 | |||
| SCL | B2 | |||
| Ground | 20 | GND | GND | 2-B |
| A0 | 3-C |
BNO085 is connected by serial. It uses xxxx-RCV mode.
Wires connected to raspberry Pi.
| GPIO | Pi pin number | BNO085 |
|---|---|---|
| 3v3 Power | 1 | VIN |
| I2C1 SDA | XX | SDA |
| I2C1 SCL | XX | SCL |
| Ground | 9 | GND |
| PC0 | 9 | GND |
https://learn.adafruit.com/adafruit-9-dof-orientation-imu-fusion-breakout-bno085
https://www.ceva-dsp.com/wp-content/uploads/2019/10/BNO080_085-Datasheet.pdf
https://docs.google.com/document/d/1icu1GVDxZhUn3ADSUc3JknNcmUMdPcsnJ4MhxOPRo-I/view
Motor controller wiring
| GPIO | Pi pin number | Cytron |
|---|---|---|
| Ground | 6 | GND |
| GPIO 12, PWM0 | 32 | PWM |
| GPIO 25 | 22 | DIR |
A microswitch to activate autosteer is connected to Raspberry Pi:
| GPIO | Pi pin number | switch |
|---|---|---|
| Ground | 30 | A |
| GPIO 27 | 13 | B |
Pololu Basic 2-Channel SPDT Relay Carrier with 12VDC Relays https://www.pololu.com/product/2485
| GPIO | Pi pin number | relay | 12V | Output |
|---|---|---|---|---|
| GND | 14 | GND | ||
| GND | GND | Out GND | ||
| VDD | +12 V | |||
| GPIO 4 | 7 | EN1 | ||
| GPIO 17 | 11 | EN2 | ||
| NO1 | Output Up | |||
| NO2 | Output Down |
There are 3 different modes for sections control.
- Impulse. 'impulse' is default 3 seconds. I use it for pneumatic cylinder to controld hydraulic lever. One GPIO pin for up and one for down motion.
- OnOff. It is just for on-off relays. I don't actually use it anywhere.
- Reverse. This uses a pair of GPIO pins and relays to reverse the polarity of voltage, e.g. 'On' is +12 V and 'Off' is -12 V. Sprayer sections control uses this one.
Sprayer pressure controller is separate feature from AgOpenGPS. Software on Raspberry Pi takes care of sprayer pressure reading and pressure control. One GPIO pin is also used to monitor whether boom is on locked position. Two GPIO pins (relays) are used to control pressure valve. There are two options for pressure control, constant pressure and speed-based variable pressure.
In my setup, this controller replaces controller for my Amazon sprayer.
Other (Windows) software is used to monitor sprayer pressure and to control settings. https://github.com/salmiac/salmiac-sprayer Software has settings screen for nozzle spacing, nozzle size selector, litres/ha, min pressure, max pressure and nominal pressure. Nominal pressure is used for constant pressure. Second screeen to monitor target pressure, current pressure and speed. Buttons for controller on/off and button to select variable or constant pressure. Also indicators for min and max speed for selected pressure range, indicator for boom locker yes/no and selected nozzle size.