Wired Controllers

GPIO-based hardware controllers provide physical switch control for OWL units. These connect directly to the Raspberry Pi GPIO pins and allow tactile control of detection, recording, and sensitivity settings.

A CAN FD-based controller is also in development for better scalability.

Ute Controller

Advanced Controller

Ute Controller

Advanced Controller

USB Drive Required

You MUST connect a USB drive when using a controller, otherwise it will not start. The SanDisk Ultra Fit Flash Drive fits within the enclosure.

Tools Required

  1. Crimping tool for Amphenol crimped connections

  2. Pliers

  3. Wire strippers/cutters

  4. Soldering iron/solder

Ute Controller

Suitable for connecting a single OWL device. TinkerCAD model available here.

Parts List

Component

Quantity

Link

Car cigarette lighter socket

1

Link

7 strand, 3mm (7.5A) trailer cable

As needed

Link

M12 Cable gland

2

Link

Off-On SPST Toggle Switch

2

Link

Rubber boot for switch

2

Link

Amphenol Fathom Lock - 6 pin plug

1

Link

#16 Contacts (13A rated)

3

Link

#20 Contacts (5A rated)

3

Link

Dialight 12V Green LED Panel Mount

1

Link

Dialight 5V Red LED Panel Mount

2

Link

M3 Heatset inserts + screws

3 + 3

Link

Ute Controller Wiring

Purpose

Colour

GPIO Pin

Connector Pin

Power +12V

Red

N/A - connect to 12V of OWL Driver Board

A (#16)

Power GND

Black

N/A - connect to GND of OWL Driver Board

B (#16)

Recording/Detection Toggle Switch

White

BOARD 36

C (#16)

Recording status LED (blinks on image save)

Green

BOARD 38

D (#20)

Storage status indicator

Yellow

BOARD 40

E (#20)

GPIO GND

Brown

BOARD 39

F (#20)

Advanced Controller

Suitable for connecting up to four OWLs. As OWL count increases, increase current ratings accordingly. For four OWLs, use four-pole switches and input power rated at least 40A @ 12V.

TinkerCAD models (1, 2, and 4 OWLs) available here.

Parts List (Core Components)

Component

Quantity

Link

In-line fuse + holder (10A per OWL)

1

30A MAX / 60A MAX

7 strand, 3mm trailer cable (comms)

As needed

Link

Output power cable (min 10A)

As needed

Link

Input power cable (10A per OWL)

As needed

10A / 25A / 50A

M16 Cable gland

1

Link

Rubber boot for switch

4

Link

Amphenol Fathom Lock - 8 pin plug

2 per OWL

Link

Amphenol Fathom Lock - 8 pin receptacle

1 (+ 1 for OWL backcover)

Link

#16 Contacts male (13A)

16 per OWL

Link

#16 Contacts female (13A)

8 (+ 8 for backcover)

Link

Dialight 12V Green LED

1

Link

Dialight 5V Red LED

1 per OWL

Link

Switches by OWL Count

1 OWL Controller:

  • Off-On SPST Toggle Switch (16A MAX) x 3

  • On-Off-On SPST Toggle Switch x 1

4 OWL Controller:

  • POWER SWITCH: Off-On SPST Toggle Switch (50A MAX) x 1

  • Off-On 4PST toggle switch x 2

  • On-Off-On 4PST toggle switch x 1

Advanced Controller Wiring

Purpose

Colour

GPIO Pin

Connector Pin

Power +12V

Red (separate cable)

N/A - connect to 12V of OWL Driver Board

A (#16)

Power GND

Black (separate cable)

N/A - connect to GND of OWL Driver Board

B (#16)

All nozzles on

Blue (trailer cable)

BOARD 36

C (#16)

Recording toggle

Green (trailer cable)

BOARD 38

D (#16)

Sensitivity toggle

Yellow/Orange (trailer cable)

BOARD 40

E (#16)

Status LED

White (trailer cable)

BOARD 40

F (#16)

Spot spray enable

Red (trailer cable)

BOARD 35

G (#16)

GPIO GND

Brown (trailer cable)

BOARD 39

H (#16)

Note

Older Advanced controller builds wired the status LED to BOARD 37. The default status_led_pin is now BOARD 40. If you use a Sixfab 4G HAT or the production CM5 carrier’s nRF9151 modem (both switch modem power on BOARD 37), move that wire to BOARD 40.

3D Printed Enclosures

File

Image

STL

Ute Controller Base

image

Link

Ute Controller Top

image

Link

Advanced Controller Base

image

Single / Double / 4 OWL

Advanced Controller Top

image

Single / Double / 4 OWL

Making Connections

Connections can be either soldered with heat shrink or connected with automotive-style blade fittings.

LEDs should be carefully soldered and covered with heat shrink.

Crimp connections for Amphenol Fathomlock connectors work best with a crimping tool. Check quality by tugging gently. Improperly crimped connections can cause problems and/or create fire risk.

Cable Protection

A Nylon Hose Protector sleeve will increase the lifetime of cabling without adding too much expense.

Config File Settings

Update the controller section of GENERAL_CONFIG.ini:

[Controller]
# choose between 'none', 'ute' or 'advanced'
controller_type = none

# Shared LED pins (BOARD numbering)
status_led_pin = 40
gps_led_pin = 38

# Ute controller (single switch)
switch_purpose = recording
switch_pin = 36

# Advanced controller (multiple switches)
detection_mode_pin_up = 36
detection_mode_pin_down = 35
recording_pin = 33
sensitivity_pin = 32

Ute Controller: The toggle switch can be used for either toggling recording or detection. Select this mode with switch_purpose. When a UTE controller is active, only the control matching switch_purpose is locked on the dashboard — the other control, nozzles, sensitivity, and fan remain controllable from the web interface.

Advanced Controller: The sensitivity switch cycles through built-in presets (Low and High) stored as [Sensitivity_Low] and [Sensitivity_High] sections in GENERAL_CONFIG.ini. Custom presets can also be saved from the dashboard. When active, recording, detection, and sensitivity are locked on the dashboard.

Warning

Modem power on BOARD 37: the Sixfab Base HAT and the production CM5 carrier’s nRF9151 modem both switch modem power on BOARD 37, and toggling it (for example with a blinking LED) power-cycles the modem. The defaults avoid it (switch_pin BOARD 36, status LED BOARD 40). With [GPS] source = nrf91 the OWL enforces this: a relay, LED or switch on BOARD 37, 21 or 24 is disabled and the dashboards refuse it.

Final Steps

With config files set, save them to the OWL, reboot, and you should be ready to go!

Next Steps