Those tiny plastic cheap servos will burn out in less than 2 seconds holding an object. The description says it can hold a ping pong ball, which will still damage them. Those blue plastic cheap servos are found in many Chinese ripoff products.

The only way to protect a servo from being damaged is to not force it to move further than physical limitations. This is because that's how a servo works, but using all its force to move into the desired position. Find out how a servo works here: https://synthiam.com/Tutorials/Lesson/48?courseId=6

Dampening/cushioning the gripper with foam is a partial solution to aid gripping. The most reliable solution is to adjust your gripper position based on the object that it is gripping, as specified in the tutorial learn section.

Take your human hand, for example. You do not attempt to close it with all your ability every time you hold an object. If you did, you would be the hulk and squish everything.

So the same common sense logic must be applied to Robotics. You cannot program a gripper servo to move to its furthest close position every time it attempts to hold something.

maybe replace the servo with one mini from here and use foam.

thanks for the link and warning.

This gripper clearly doesn't have this, but it is possible to design a gripper with a clutch so the servo keeps spinning but the clutch slips when it squeezes too tightly on an object. I have a cheap robot arm that uses just hobby motors and switches to operate and all of the joints and the grippers are clutched. I don't like the overall design of the grippers but if I ever manage to get a 3d printer I will use some elements of the design to make something better.

That being said, as DJ pointed out, that advertisement is simply a lie.

Alan

You can use a clutch - i have seen magnetic ones. However, you lose positioning.

Is there such a thing as servo's with force feedback? i.e. A way to detect resistance in the gripping action and prevent an attempt to move the server further once the resistance reaches a prescribed level?

I know there are all sorts of pressure sensors available separately, so I'm betting it's been found that simple resistance to the servo motor is inadequate, but I'd be interested to know why. Is it that you have to apply a large force before obtaining the resistance, thereby only knowing after the effect that you've squished the object already?

A Lego sleep gear could do the job

Lego gear with clutch

@Aceboss you can get into dynamixel servos with a dramatic increase in cost - but they do exist. The feedback mechanism requires you to program the expected values - and if you make a mistake with a dynamixel servo, the mistake cost is 2 or 3 times

If you add a feedback line to the potemeter, you can monitor if the servo movement stopped and set it to that position or one less. That's the only other way.