Abstract: Among other features, a time series of values of an electrical parameter of an electrical system of a vehicle is accessed. An event or a state of the vehicle is determined based on the time series of values of the electrical parameter. The event or state is communicated to an occupant of the vehicle or to a third party.

Abstract: Among other features, a time series of values of an electrical parameter of an electrical system of a vehicle is accessed. An event or a state of the vehicle is determined based on the time series of values of the electrical parameter. The event or state is communicated to an occupant of the vehicle or to a third party.

Abstract: A multi-radio sensor node is provided that includes two or more communication devices. The communication devices include radio frequency (RF) devices like radios. Each communication device supports simultaneous communications among multi-radio sensor nodes of respective independent network clusters. A network structure is provided that includes two or more local network clusters. Each local network cluster includes numerous multi-radio sensor nodes. Each communication device of a multi-radio sensor node supports communication among the multi-radio sensor nodes of a different one of the local network clusters so that simultaneous communications are supported among the multi-radio sensor nodes of the local network clusters. The multi-radio sensor nodes of the local network clusters determine their locations relative to the other multi-radio sensor nodes of the independent network clusters with which they communicate.