Tactile sensing or touch sensing is one of the primary challenges in robot building and manipulation. The agile environment in which a robot works also requires pressure sensors to determine the careful operation of an object.
A robot skin is developed to mimic the touch senses perceived by human skin, integrating different types of tactile sensors. By doing so, a robot ‘feels’ many classes of objects – flexible, rigid, hard, soft, fragile, etc. This allows the robots to work in close proximity to humans while performing tasks of higher risk factors.
Building robots using tactile sensors
Cobots are robots that work hand-in-hand with humans in high-risk environments. The first cobot was built in 1996 for pick and place applications, which were communicated using motion resistance technology through computerized programs. Since then, cobots have come a long way in working with humans and detecting the environment around them with the help of vision and other types of sensors.
Modern cobots can take corrective actions with slight decision-making skills and sophisticated software. In addition, tactile sensors are now used to increase these cobots’ applicability and safety, especially in environments requiring delicate handling of objects, such as healthcare.
The use of tactile sensors
Piezoelectric, Pierzoresistive, capacitive, and electroresistive are the four types of tactile sensors in use today. A combination of all these types is used in building robots and cobots by transmitting their actions to a controller, thereby managing their sensitivity towards an object and their motion in different directions.
For some applications, detection sensors are placed outside the body of a collaborative robot which helps recognize human workers when they work closely. These sensors signal the robots to slow down or stop when an object is near.
Although collisions can take place to a certain extent, the impact of the collision can be minimized. However, tactile sensors are empowered with intelligent software technologies to improve the readability of these collaborative robots.
Precise object handling
Tactile or touch sensors are used in applications requiring precise object placements, like loading parts into a machine. The sensitive sensing technology provided by tactile sensors embedded in a robot’s body will help determine the exact location and the correct position to place the stock material with the help of insertion force.
Modern-day touch sensing technologies use tactile sensors to study the real-time parameters of an object like the shape, texture, size, etc. and determine highly accurate data of the object, which can also help determine defects and damages in an object. For example, cobots powered by tactile sensors can be used in surgery to interact with more fragile and deformable objects. However, multiple tactile sensors should be used to build empathetic robots, integrating them with AI and machine learning technologies.
