Industrial robots are very good at repeating the same movement, but repeatable motion does not automatically mean gentle handling. Products such as food, cosmetics or flexible consumer goods can vary in shape and may be damaged when force is concentrated in a small area. These characteristics make them harder to automate than rigid machined components.
Soft robotic gripping addresses this problem by using compliant contact surfaces that can adapt to the object rather than relying entirely on rigid fingers.
Why compliance can improve handling
A conventional rigid gripper often works best when the component geometry is stable. The fingers can be designed around predictable surfaces, allowing the robot to locate and hold the part accurately.
Delicate products create a narrower operating window. Too little force allows the item to slip, while too much pressure can leave marks or deform it. Variation between individual products can make the problem even more difficult.
A soft gripper uses flexible contact elements intended to conform more readily to different shapes. OnRobot currently positions its electrically operated Soft Gripper for handling irregular or delicate products in applications that include food, packaging and manufacturing.
That does not make soft gripping suitable for every object. Friction, geometry, weight and surface condition still influence whether the grip will be reliable.
Irregular products need to be tested as a range
An engineering trial can be misleading if it uses only the best possible product sample. Real production contains variation, and that is particularly true in areas such as food handling.
Two items from the same product category may have different diameters, curvature or surface conditions. The smallest and largest expected examples should therefore be included during testing, along with realistic orientations.
The purpose is not simply to prove that the robot can lift the product once. The system has to repeat the operation over thousands of cycles without creating an unacceptable level of dropped or damaged items.
Hygiene introduces another design requirement
Applications involving food or other sensitive products require more than mechanical compatibility. Materials, cleaning procedures and the design of the surrounding equipment may all be important.
A soft gripping tool that performs well mechanically still needs to fit the hygiene requirements of the specific production environment. Cleaning frequency, exposure to moisture and the type of product being handled can influence whether the solution is practical.
This is one reason why manufacturers should avoid assuming that the term “soft gripper” describes one universal technology. Different designs use different materials and actuation methods, and their suitability needs to be assessed individually.
Electric and pneumatic systems take different approaches
Soft gripping can be produced using several methods. Pneumatic designs are common, particularly where factories already have compressed-air infrastructure. Electric systems can simplify installation in applications where an external air supply is undesirable.
Neither approach is inherently superior. Pneumatics can be robust and familiar, while electric actuation may reduce some peripheral equipment. The most appropriate choice depends on the production environment, required cycle time and maintenance strategy.
The same practical thinking should apply to the complete cell. A technically elegant gripper is of limited value if it complicates cleaning or requires maintenance skills that the plant does not have.
Gentle handling is about control, not weakness
Soft gripping is sometimes interpreted as simply applying less force. That misses the main advantage.
The objective is to distribute and control contact in a way that accommodates the product. A compliant gripping surface can reduce local pressure and handle some dimensional variation without requiring a perfectly matched rigid finger.
The best applications are those where this behaviour solves a genuine production problem. If a rigid gripper already handles the component reliably without damage, there may be little reason to replace it. Soft grippers are most valuable where product variation and sensitivity have previously made conventional automation difficult.