An article of manufacture comprising: a stationary component; and a rotatable component configured to rotate with respect to the stationary component, wherein: the stationary component comprises a stationary infra-red IR communicator; and the rotatable component comprises a stirring shaft and a rotating communicator connected to rotate with the stirring shaft with respect to the stationary communicator of the stationary component, wherein the stationary and rotating communicators (108 and 110) communicate in a contactless manner while the rotatable component rotates with respect to the stationary component; the rotating communicator comprises a first infra-red IR transmitter (118); the stationary communicator comprises a first IR receiver; and the contactless communication between the rotating communicator and the stationary communicator comprises transmission of an IR signal from the first IR transmitter (118) of the rotating communicator to the first IR receiver of the stationary communicator, CHARACTERIZED IN THAT: as the rotatable component rotates with respect to the stationary component, the IR signal from the first IR transmitter (118) to the first IR receiver is occasionally blocked by the rotatable component; and the first IR transmitter (118) transmits the IR signal at irregular intervals to avoid repeatedly transmitting when blocked. a stationary component; and a rotatable component configured to rotate with respect to the stationary component, wherein: the stationary component comprises a stationary infra-red IR communicator; and the rotatable component comprises a stirring shaft and a rotating communicator connected to rotate with the stirring shaft with respect to the stationary communicator of the stationary component, wherein the stationary and rotating communicators (108 and 110) communicate in a contactless manner while the rotatable component rotates with respect to the stationary component; the rotating communicator comprises a first infra-red IR transmitter (118); the stationary communicator comprises a first IR receiver; and the contactless communication between the rotating communicator and the stationary communicator comprises transmission of an IR signal from the first IR transmitter (118) of the rotating communicator to the first IR receiver of the stationary communicator, CHARACTERIZED IN THAT: as the rotatable component rotates with respect to the stationary component, the IR signal from the first IR transmitter (118) to the first IR receiver is occasionally blocked by the rotatable component; and the first IR transmitter (118) transmits the IR signal at irregular intervals to avoid repeatedly transmitting when blocked. the stationary component comprises a stationary infra-red IR communicator; and the rotatable component comprises a stirring shaft and a rotating communicator connected to rotate with the stirring shaft with respect to the stationary communicator of the stationary component, wherein the stationary and rotating communicators (108 and 110) communicate in a contactless manner while the rotatable component rotates with respect to the stationary component; the rotating communicator comprises a first infra-red IR transmitter (118); the stationary communicator comprises a first IR receiver; and the contactless communication between the rotating communicator and the stationary communicator comprises transmission of an IR signal from the first IR transmitter (118) of the rotating communicator to the first IR receiver of the stationary communicator, CHARACTERIZED IN THAT: as the rotatable component rotates with respect to the stationary component, the IR signal from the first IR transmitter (118) to the first IR receiver is occasionally blocked by the rotatable component; and the first IR transmitter (118) transmits the IR signal at irregular intervals to avoid repeatedly transmitting when blocked. as the rotatable component rotates with respect to the stationary component, the IR signal from the first IR transmitter (118) to the first IR receiver is occasionally blocked by the rotatable component; and the first IR transmitter (118) transmits the IR signal at irregular intervals to avoid repeatedly transmitting when blocked.