A peening calibration system comprising: a plurality of peening calibration units, each peening calibration unit comprising: a casing defining a top and a bottom; a transducer along at least a section of the top of the casing, the transducer generating an electric signal upon application of peening energy thereto; a transmission unit for receiving the electric signal generated by the transducer and transmitting a digital signal representative of the electrical signal wirelessly, the transmission unit being located inside the casing; and a battery, the battery powering the transducer and the transmission unit; and a computing device comprising: a communication unit for receiving the digital signal representative of the electrical signal transmitted by the transmission unit of each peening calibration unit; a processor for processing the digital signal received from the plurality of peening calibration units; and a memory for storing the received digital signal together with an identification of the peening calibration unit the digital signal is received from and at least one of the following: a timestamp or a time interval; characterized in that the transducer is - casted inside the casing or - mixed into the material used for the casing in the form of powder or nano-particles. a plurality of peening calibration units, each peening calibration unit comprising: a casing defining a top and a bottom; a transducer along at least a section of the top of the casing, the transducer generating an electric signal upon application of peening energy thereto; a transmission unit for receiving the electric signal generated by the transducer and transmitting a digital signal representative of the electrical signal wirelessly, the transmission unit being located inside the casing; and a battery, the battery powering the transducer and the transmission unit; and a casing defining a top and a bottom; a transducer along at least a section of the top of the casing, the transducer generating an electric signal upon application of peening energy thereto; a transmission unit for receiving the electric signal generated by the transducer and transmitting a digital signal representative of the electrical signal wirelessly, the transmission unit being located inside the casing; and a battery, the battery powering the transducer and the transmission unit; and a computing device comprising: a communication unit for receiving the digital signal representative of the electrical signal transmitted by the transmission unit of each peening calibration unit; a processor for processing the digital signal received from the plurality of peening calibration units; and a memory for storing the received digital signal together with an identification of the peening calibration unit the digital signal is received from and at least one of the following: a timestamp or a time interval; characterized in that the transducer is - casted inside the casing or - mixed into the material used for the casing in the form of powder or nano-particles. a communication unit for receiving the digital signal representative of the electrical signal transmitted by the transmission unit of each peening calibration unit; a processor for processing the digital signal received from the plurality of peening calibration units; and a memory for storing the received digital signal together with an identification of the peening calibration unit the digital signal is received from and at least one of the following: a timestamp or a time interval; - casted inside the casing or - mixed into the material used for the casing in the form of powder or nano-particles.