Nitinol Wire Characterization: Nitinol phase transition temperature was tested both by DSC and water bath test. 22.86 mg Nitinol sample was cut from the pre-set Nitinol coil. Mettler Polymer DSC (Mettler Toledo, Columbus, Ohio, USA) using STARe software (version 16.10) was used to perform DSC test by sweeping the temperature between 0 ℃ to 150 ℃ at a heating rate of 20 ℃ per minute. For the water bath test, we heated a beaker of water while monitoring the temperature. Stretch the coiled Nitinol wire, immerse it into a water bath at different temperatures and record the length change.