Strawberry Sorting with a Rochu Soft Gripper
Strawberries look simple to handle. But for automation engineers, picking them without causing damage is not always easy.Each strawberry has a different shape, size, and level of ripeness. Some are round, while others are longer or more irregular. A gripper that works well for one fruit may not perform the same way with another.In this application, we used a Rochu soft gripper with flexible wing modules to handle strawberries during sorting.The goal was straightforward: grip different strawberries gently, keep them stable during transfer, and reduce the need for repeated adjustments.
Why Is Strawberry Sorting Difficult?
Strawberries are delicate. Excessive pressure can damage their surface, while an unstable grip can cause them to slip during transfer.For engineers, three challenges stand out.1. Controlling gripping forceA gripper needs enough force to hold a strawberry securely. Too much force may damage the fruit. Too little force may cause it to slip.Finding the right balance is essential.2. Handling different shapesStrawberries are not uniform. Their shape and size can vary even within the same batch.Rigid grippers rely on fixed contact points. When the fruit changes shape, the contact position and pressure may also change.3. Switching between product sizesAutomated sorting lines often handle different strawberry specifications.If every size change requires engineers to adjust the gripper opening or gripping parameters, the process becomes more complicated.This is where adaptive gripping can help.
How Do Flexible Wings Handle Strawberries?
For this application, we selected a Rochu soft gripper equipped with flexible wing modules.The wings provide a flexible contact surface. When they touch a strawberry, they can deform to follow its shape.This changes how the gripper interacts with the fruit.
A larger contact area
A rigid gripper may contact a strawberry at only a few points. This can concentrate pressure on specific areas.Flexible wings can conform to the fruit's surface. This helps distribute contact pressure over a larger area.The result is a gentler gripping approach.However, soft materials alone cannot guarantee damage-free handling. Gripping force, fruit ripeness, contact position, and transfer speed all affect the result.Engineers still need to test the gripper with actual strawberries.
Better adaptability to different sizes
Strawberries vary in size and shape.The flexible wings can adapt to these differences during contact. This reduces the need to rely on a fixed gripping geometry.When switching between different fruit sizes, the gripper may require fewer adjustments.The actual gripping range still matters. Engineers need to check the strawberry dimensions, gripper opening, and mounting position before selecting the configuration.
What Should Engineers Test?
A soft gripper that can pick up one strawberry is not necessarily suitable for an automated sorting line.The more important question is how it performs during repeated handling.Here are some key points engineers should check:
| Test | What to Check |
|---|---|
| Grip stability | Does the strawberry stay in place during transfer? |
| Surface condition | Are there visible marks or signs of damage? |
| Size adaptability | Can the gripper handle different fruit sizes? |
| Parameter adjustment | Does changing fruit size require new settings? |
| Continuous operation | Does the grip remain stable over repeated cycles? |
Food handling also brings additional requirements.Engineers need to consider food-contact materials, cleaning methods, and the production environment.These details matter when choosing a soft gripper for real production.
What Does Adaptive Gripping Mean for Food Automation?
Strawberry sorting is one example of how soft robotic grippers can support food handling automation.The key is not simply using a softer material.It is the ability to adapt to the shape of the workpiece and the conditions at the contact surface.For delicate food products with different sizes and shapes, this can make automated handling more flexible.Of course, a soft gripper is not suitable for every application. Workpiece dimensions, weight, surface condition, gripping direction, and cycle time all affect the final solution.For engineers, the best approach is to start with the workpiece, select a suitable gripping method, and verify the result through testing.If you are exploring soft grippers for strawberry sorting, berry handling, or other delicate food applications, Rochu flexible wing grippers are worth testing.
Have a workpiece that needs gentle handling?Visit the Rochu website to explore our soft grippers, gripper kits, and application cases.You can also contact us to discuss your workpiece and gripping requirements.