In the field of industrial automation, machines require sensors to provide essential information to perform their operations correctly. Robots have begun to utilize a large number of sensors to improve their adaptability. For example, many collaborative robots integrate torque sensors and cameras to ensure a better field of view during operation and to guarantee the safety of the work area. Here is a list of some commonly used sensors that can be integrated into robot units for your reference.
2D vision sensor
2D vision is essentially a camera capable of performing multiple tasks, from detecting moving objects to locating parts on a conveyor belt. 2D vision has been on the market for quite some time and holds a significant market share. Many smart cameras can detect parts and assist robots in determining their positions, allowing the robots to adjust their movements accordingly based on the received information.
3D vision sensor
Compared to 2D vision, 3D vision is a more recent technology. A 3D vision system must have two cameras at different angles or use a laser scanner. This is how it detects the third dimension of an object. Similarly, many applications now utilize 3D vision technology. For example, in parts handling, 3D vision technology detects objects and creates 3D images, analyzes the data, and selects the best picking method.
If vision sensors give robots eyes, then force/torque sensors give them touch. Robots use force/torque sensors to sense the force applied to the end effector. In most cases, the force/torque sensor is located between the robot and the gripper, so all forces fed back to the gripper are under the robot's monitoring.
With force/torque sensors, applications such as assembly, manual guidance, teaching, and force limiting can be realized.
Collision detection sensor
These sensors come in various forms. Their primary application is to provide a safe working environment for operators, and they are most essential for collaborative robots. Some sensors can be tactile recognition systems that sense pressure through soft surfaces; if pressure is detected, they send a signal to the robot to restrict or stop its movement.
Some sensors can even be built directly into the robot. Some companies use accelerometer feedback, while others use electrical feedback. In both cases, when the robot senses abnormal force, it triggers an emergency stop, thus ensuring safety. However, you can still be bumped by the robot before it stops. Therefore, the safest environment is one with absolutely no risk of collision, which is the mission of the sensor described below.
To enable industrial robots to collaborate with humans, the first step is to find ways to ensure worker safety. These sensors come in various forms, from cameras to lasers, but their purpose is the same: to inform the robot of its surroundings. Some safety systems can be programmed to automatically slow the robot down when someone enters a specific area/space, and to stop working if the person continues to approach.
The simplest example is the laser safety sensor on an elevator door. When the laser detects an obstacle, the door immediately stops and reverses to avoid a collision. Most safety sensors in the robotics industry work similarly.
Part Inspection Sensor
In parts picking applications (assuming no vision system), you cannot know whether the robotic gripper has correctly picked up the parts. Part inspection applications, however, can provide feedback on the gripper's position. For example, if the gripper misses a part, the system will detect the error and repeat the process to ensure the part is picked up correctly.
Other sensors
There are many other sensors on the market suitable for different applications. For example, weld seam tracking sensors.
Tactile sensors are also becoming increasingly popular. These sensors are typically mounted on grippers to detect and feel what is being grasped. The sensors can usually detect force and determine the force distribution, thus knowing the object's exact location, allowing you to control the gripping position and the gripping force of the end effector. Some tactile sensors can also detect changes in heat.
Finally, sensors are a key component for realizing software intelligence. Without these sensors, many complex operations would be impossible. They not only enable complex operations but also ensure that these operations are well controlled during their execution.
