i think and emp/ heat barrier would be the fastest way to stop a robot or a tazer... but really just have fail safes to lets say you program said robot to have AI and every time the robot makes a "Discovery" (like war and death and stuff) it will power off then the owner/master can go and delete the file if he or she so chooses or just turn it back on it would stop any problem before it began and also just plant pieces of c4 in it and rig it so if the robot tries to remove it they will explode and have them as small pieces and plant them on the motherboard so they can be destroyed anywhere and not endanger others if they have no be put down