Laser displacement sensor adopts the principle of laser triangular reflection, measuring spot is a point, commonly known as point laser. In essence, the measuring principle of laser profile scanner is triangular reflection, but the imaging CCD is a group, and the measuring spot is a line, so it is commonly called line laser. The measurement accuracy of point laser is high, but if we want to measure all the topography of the object in a large area, the efficiency will be low, because we need to measure point by point. Linear laser can scan the surface and form 3D contour quickly, but the accuracy will decrease. The specific choice depends on the requirements of the actual measurement task.

Laser displacement sensor and laser profile sensor are both sensors based on the principle of laser triangulation. Laser displacement sensor emits point laser to measure one-dimensional displacement, while laser contour sensor emits line laser to measure two-dimensional contour shape. Therefore, there are obvious differences and adaptability between them.

Sensors, as the basis of the Internet of Things, are the key equipment to support the operation of the Internet of Things. Nowadays, Internet of Things (IOT) technology is widely used in shared bicycles, and it will also focus on the input of sensors in virtual parking spaces. These data collected by sensors will be open to management departments and shared bicycle enterprises. These data can not only be used to manage shared bicycles, but also reflect the real-time traffic conditions in the region. As the electronic fence gradually covers the whole country, a nationwide networked "shared sensor" industry will soon be born.

At present, many foreign public institutions have begun to establish open data portals in the field of transportation. With the rapid development of urban transportation in China, these data will provide great convenience for relevant departments to solve the traffic safety situation, but at the same time, these data also involve national security, and most applications of sensor networks are facing serious security problems. Therefore, the first thing to do is to improve the localization of sensors and reduce safety risks.