Flexible gripper: getting softer and smarter

Throughout the history of mankind, we’ve received so many whimsical sparkles from the nature. From submarine and torpedo to airplane and radar, mankind keeps learning and improving. So is the hero of this blog: flexible gripper. By the inspiration of octopus’ tentacles, professionals imitate the movement of octopus grabbing objects in order to achieve fully wrapping. In what kind of technique does professionals adopt to reach the target and hit the bullseye?

Working principles of flexible grippers

Generally, to motivate the fingers while grabbing, flexible grippers have two major ways of en-powering: through air or electricity. Both methods are adjusted to different working environment and have its own pros and cons.

• Air enpowered:

Through the exchange of positive/negative pressure to realize the goal of expanding or grabbing. At the same time, adjusting the air pressure can also control the strength and angles of grippers to gently grab different objects without any harm. It’s worth noting that the chucking power needs to be carefully calculated to avoid the accidental falling off of objects. The chucking power can be calculated taking the factors of shapes of objects, types of fingers, area of fingers touching objects, distance between fingers and the working pressure into consideration.  

• Electricity enpowered:Pros: More precise and stronger stability.

Most of electricity enpowered grippers are based on stepping motor. The working principle behind it is switching electric pulse into angular displacement. By controlling the number of pulses, it can position precisely. Meanwhile, the frequency of pulses is also a factor of controlling the speed. An electricity enpowered flexible gripper is deemed as more precise and more stable when it comes to controlling the chucking power. However, it does cost more no matter in purchasing one or the maintenance.

In general, all grippers (flexible or not) are designed based on the mentioned three principles. Since the development of technology, the applications of grippers are widely depends on traditional manufacturing industry such as automobile, 3C, stacking and unstacking in factories, etc. Basically, everywhere you can imagine with a safety helmet, grippers can work in. Yet grippers (esp. flexible grippers)are more and more widely adopted in unexpected fields, bringing windfall to various of industries in recent years.

Applications of flexible grippers

Keep in mind that flexible grippers are designed to be softer and safer for industries which are closer to our daily life. For example, the food we have, the groceries we purchase, the medicine we take are all just a tip of the iceberg. Therefore, flexible grippers are seen more and more often in the following fields:

• Fresh food

Flexible grippers dipping in this industry are required to be extremely safe and guarantee that no chemical or appearance harm exist in the process of dealing with freshly harvest vegetables and fruits. In order to achieve the goal, certain flexible grippers pass the test of FDA and guarantee that it is safe to touch the food directly. The kind of flexible grippers can work as a part of harvest such as fruits. Even strawberry can be harvested by them due to the special design to make sure the process is gentle enough to handle delicate objects.

• Food-processing industries

The main obstacles in this certain industry are the grabbed objects often appear to be in irregular shape, which is challenging to robots and grippers. Traditional grippers can only form the fingers in certain positions. When facing objects in irregular shapes, there’s a chance that the grabbing is not firm and tight enough to hold them. Flexible grippers perfectly solved the problem by adding a layer of plastic structure right outside the silica-gel. With the particular design, flexible grippers are able to fully warp the objects.

• Fashion industry

This may surprise you, but it is true. Some companies in fashion industry have already adopted flexible grippers to help them speed up in the process of apparel manufacturing. Some materials in the industry are delicate as well. A rough grabbing can cause waste in raw materials. The strength of flexible grippers can be adjusted manually by settings to further avoid the issue.

With all that being said, what are the specific advantages of flexible grippers? The following segment may help you further understand them.

Advantages of flexible grippers

• Compatible: Pared with standard finger module and standard communication port, making the setting up process as easy as building stocks. The standard communication port makes sure that it’s adjustable to all common kinds of robotic arms and PLC. The maximum grabbing speed is up to 300 times/min with the maximum positioning accuracy of 0.08mm. Even an object as heavy as 9kg is not a challenge for flexible gripper. With the service life achieving millions of times, it’s qualified for most of industrial situations.

• Safety assurance: Flexible grippers are made of pure soft materials with adjustable strengths which means they won’t cause any harm to delicate objects. It is crucial to both the grabbed objects and the operating staff. The material passed the test of FDA food grade standard to work in fresh food industry. Moreover, due to the materials being highly resistant of high temperature and chemicals, some tough conditions are piece of cake for flexible gripper.

• Convenient : Supporting wireless control and easy to work in mobile environment. The biomimetic kind of flexible gripper can adjust to the shapes of objects automatically due to the ability of wrapping the whole objects.