For added safety, vehicles using PIXHAWK or PX4IO have to use an on-vehicle safety switch. The switch includes a status led and should protrude through the vehicle body. It allows to arm a fixed-wing aircraft immediately before takeoff and indicates the system status.
Where to Buy
Dimensions and Pin Locations
Many models can be used, the recommended choice is the E-Switch model LP1OA1AG (Datasheet).
Schematic and Wiring
If you want to wire up your own safety switch, connect these pins of PX4IO and the switch:
|PX4IO J17 pin||Switch pin||Note|
|1 (3.3V)||4||Just make the wire a bit longer and solder it to pins 3 and 4 at once.|
The LED is controlled by the MCU on PX4IO and the switch pulls pin 3 of J17 high when closed.