TaserX26 current increases with dart depth

The TaserX26 output current waveform consists of an arc phase and a stimulation phase, which is responsible for electromuscular stimulation. We modeled the current discharge during the stimulation phase using a simplified overdamped series R-L-C circuit. The model provides a reasonable approximation to the TaserX26 current waveform and explains the changes in the peak current and rise and fall time constants due to load variations. We simulated a physiological load using a 0.2% saline solution in a 75 × 30 × 17.2 cm fish tank to represent a supine human torso with resistivity similar to skeletal muscles. The peak current and load resistance varied more with the depth of the Taser darts in saline than with their distance of separation. Experiments performed on three pigs confirmed the decrease in resistance and increase in current with the depth of the Taser dart in the body. An R-C circuit with a time constant of about 2 ms was used to measure the variation of the Taser in stimulating cardiac cells. The Taser is 2.05 times more likely to stimulate the cardiac cell when the darts penetrate 9 mm into the load as compared to when they were just touching the load.