extern void Sensor_Spawn(); // Initialise sensor
extern void Sensor_Join(); //Join sensor threads
extern void * Sensor_Main(void * args); // main loop for sensor thread; pass a Sensor* cast to void*
extern void Sensor_Spawn(); // Initialise sensor
extern void Sensor_Join(); //Join sensor threads
extern void * Sensor_Main(void * args); // main loop for sensor thread; pass a Sensor* cast to void*