According to the British Daily Mail, robots have been used on production lines for decades to automate the processing and assembly of many products quickly, such as computer parts and automotive parts. Although mechanical arms are very practical, they still lack the human arm-like touch. Currently, scientists design a soft mechanical arm that can detect the texture and shape of an object by touching. The researchers hope that the soft arm will become a more sensitive prosthesis or help the surgeon perform the surgery. Based on current technology, in order for the robot to grip the object, an electric motor or a fluid joint that conducts electrical signals is usually required. At present, engineers at Cornell University in the United States adopt a different approach. They use light-carrying signals combined with extensible sensors to detect the external environment by changing the light signals they carry and the light will be distorted or bent . During the testing of the sensor, Cornell's team combined the sensors with a soft robot arm that grasps three tomatoes with their fingers, applies pressure on the tomatoes to calculate how hard they are based on the light signal twist , At the same time found the ripe condition of tomato. At present, this latest research is published in the recently published "Scientific Robot Technology" magazine.