Sensors for monitoring shock or vibration of an object are provided. The sensors include a proof mass, at least piezoelectric device, and an electronic circuit connected to the piezoelectric device. The piezoelectric device generates a current when the proof mass imparts a force on the piezoelectric device in response to the proof mass being subjected to a transient acceleration when the object is subjected to a shock or vibration. The electronic circuit is at least partially controlled in response to the current generated from the piezoelectric device due to the shock or vibration. Embodiments of the sensor provide multi-axis sensing capabilities. Methods of making the sensors and flexible circuits are also provided.