Rail sensor unit

A rail sensor unit for attachment to a rail of a rail track, for sensing by physical attachment to the rail at least one physical parameter associated with objects interacting mechanically with the rail, the sensor unit comprising a housing-, at least one transducer within the housing for sensing the parameter transmitted to the rail sensor through physical attachment to the rail, and electronic circuitry within the housing for receiving a signal from the at least one transducer, the electronic circuitry having a controllable dynamic range configuration settable in at least:

• (i) a first configuration for handling a relatively weak occurrence of the physical parameter to be sensed by the at least one transducer, and (ii) a second configuration for handling a relatively strong occurrence of the physical parameter to be sensed by the at least one transducer and wherein the electronic circuitry further comprises a controller for dynamically switching between the dynamic range configurations.

A rail sensor unit for attachment to a rail of a rail track, for sensing by physical attachment to the rail at least one parameter associated with objects interacting mechanically with the rail, the sensor unit comprising a housing, a transducer within and coupled to the housing for sensing the parameter transmitted to the rail sensor through physical attachment to the rail, and an at least partly flexible printed circuit substrate within the housing, the circuit substrate having a first zone on which is mounted the transducer and first electronic circuitry for receiving a signal from the transducer, and a second zone on which is mounted second electronic circuitry for processing a signal after processing by the first electronic processing circuitry, the circuit substrate having a folded configuration within housing.

A method of operation in a rail sensor unit, the rail sensor unit configured for attachment to a rail of a rail track, for sensing by physical attachment to the rail at least one physical parameter associated with objects interacting mechanically with the rail, the sensor unit comprising a housing, at least one transducer within the housing for sensing the physical parameter transmitted to the rail sensor through physical attachment to the rail, and electronic circuitry within the housing for receiving a signal from the at least one transducer, the method comprising:

• operating a controller to dynamically set a controllable dynamic range configuration of the electronic circuitry selectively between at least (i) a first configuration for handling relatively a weak occurrence of the physical parameter to be sensed by the at least one transducer, and (ii) a second configuration for handling a relatively strong occurrence of the physical parameter to be sensed by the at least one transducer.