US Patent 10221643 Downhole tools having controlled degradation and method

A downhole assembly includes a downhole tool including a degradable-on-demand material, the degradable-on-demand material including a matrix material, and a unit in contact with the matrix material, the unit including a core comprising an energetic material configured to generate energy upon activation to facilitate degradation of the downhole tool and, an activator disposed in contact with the core, the activator having a triggering system including an electrical circuit, an igniter in the electrical circuit arranged to ignite the energetic material, a sensor configured to sense a target event or parameter within the borehole, and a control unit arranged to receive sensed signals from the sensor and to deliver a start signal to the electrical circuit in response to the sensed signals indicating an occurrence of the target event or parameter wherein, after the start signal is delivered from the control unit, the electrical circuit is closed and the igniter is initiated.