Top 10 industrial robot sensors for enhanced automation
Introduction
An industrial robot is a programmed mechanical device that performs production-related jobs automatically in industrial environments. In the industrial and automation world, robots use sensors to create a picture of their surroundings. Industrial robots utilise several sensors to achieve reasonable control and operation in industrial automation production processes. The manufacturer can add various sensors to different robots to increase their adaptability, ensuring higher profitability with a lower cost per product by reducing the potential for human fatigue and error. This article discusses, in brief, the top ten necessary industrial robot sensors.
Sensors used in industrial robots
The continuous and rapid introduction of several new sensor technologies plays an essential role in developing more advanced industrial robots. The ten most used sensors in industrial robots are:
- Two-dimensional vision sensor
It is a smart camera that can perform many tasks, including detecting moving objects and finding parts on the conveyor belt. The robot can appropriately adjust its motion based on the received information.
Figure 1: Two-dimensional vision sensor
- Three-dimensional vision sensor
The 3D vision system can detect the object’s third dimension. It uses two cameras or laser scanners at different angles to perform its function. For example, part picking and placing using 3D vision technology to detect objects and create 3D images. It also analyses and selects the best picking method.
Figure 2: Three-dimensional vision sensor
- Navigation (positioning) sensors
Navigation or Positioning sensors approximate the robot’s position. The standard positioning sensor is a GPS (Global Positioning System). A robot receiver acquires and processes signals transmitted by orbiting satellites. It uses the processed information to locate a robot’s velocity and approximate position.
Figure 3: Navigation (Positioning) Sensor
- Gyroscope sensor
A gyroscope sensor or Gyro measure uses the angular momentum principle to help maintain orientation. It helps to calculate the rate of revolution in the region of a particular axis. This sensor enables your robot to be independent of the earth's gravity to maintain orientation.
Figure 4: Gyroscope sensor
- Sound sensors
Sound sensors in robotics work similarly to microphones and connect to circuits that evaluate the amplitude of the sounds to a particular threshold value and report the result to the robot. The noise becomes louder with the increase in amplitude. A simple application is a robot programmed to study wildlife. The sensor can detect and follow loud noises and make them data points for wildlife locations. A more complex application for sound sensors is voice recognition, where the robot responds to commands uttered by the user.
Figure 5: Sound sensor
- Proximity sensors
A proximity sensor in robotics can detect (or ‘sense’) a nearby object without physical contact. The transmitter sends electromagnetic radiation to the adjacent sensor, and the receiver receives and then analyses the interruption feedback signal. The amount of light received inside the area can help to determine the presence (or absence) of neighbouring objects. For the robot, the sensors offer a collision avoidance approach.
Infrared (IR) transceiver: an IR LED directs an IR beam of light at a target area, any light that is reflected from an object within this area is detected creates an electrical signal.
Ultrasound sensor: These sensors generate high-frequency sound waves, and the recorded echo indicates the presence of an object. Ultrasound sensors can measure distances as well.
Figure 6: Proximity sensor
- Touch sensors
Touch Sensors (aka contact sensors) are devices that can detect the touch of an object. These are found in small devices such as micro-switches and limit switches. Robots deploy these sensors to avoid obstacles. The sensors indicate whether the robot can reverse, stop, switch on, turn, and so on if it encounters an obstruction.
Figure 7: Touch sensor
- Force sensors
Force sensors calculate the forces necessary in a robot's various functions, such as material management, machine loading and unloading, or material management. This sensor improves the assembly process for troubleshooting. A force-torque sensor provides the robotic arms with the feel of completing an assembly task, and the internal state sensors measure the end effector.
Figure 8: Force sensor
- Acceleration sensors
Acceleration sensors measure the acceleration and tilt of the robot. Two types of forces affect an accelerometer.
Static force: It is the frictional force that exists between two objects. You can measure this gravitational force to determine how much the robot tilts. This parameter helps balance robots. It can also assess whether a robot is on a flat surface or an incline.
Dynamic force: It is the acceleration needed to move an object. You can find the speed or velocity of the robot by measuring its dynamic force using an accelerometer.
Figure 9: Acceleration sensor
- Temperature sensors
Temperature sensors measure heat or temperature changes in their surrounding environment. There are various methods used to measure temperature such as using materials that change resistance, or some that generate changes in voltage across a semiconductor junction when heated or cooled.
Air temperature, immersion temperature, and surface temperature are all applications for temperature sensing.
Figure 10: Temperature sensor