Example devices, systems, and methods for structural health monitoring of composite structures are disclosed. One example method includes attaching a device to an object by fitting the device around the object, where the device includes an enhanced magnetorheological elastomer (MRE) and an elastomer, the enhanced MRE has a folded pattern, the enhanced MRE is embedded in the elastomer, and the device is configured to output a voltage signal generated by the enhanced MRE based on a strain induced on the device in response to deformation. A digital signal is generated based on the voltage signal and using a data processing system, where the data processing system includes a Wheatstone bridge, an amplifier, and an analog-to-digital convertor. A strain value associated with the object is determined based on the digital signal.