[tmoney1818]

From my research, maybe the most interesting characteristic is that all these companies seem dependent on the sucker gripper. I haven't worked in this field, but you'd think it'd be easy getting other gripper to work well, especially since covariant is combining simulated training with non-simulated training.

[sgillen]

I think that the communities experience has led them to the belief that the suction gripper is simply the most effective gripper currently available. It’s possible to get other grippers working in theory, but I think if you want reliability suction on constrained packages is the way to go.

[NalNezumi]

As someone in robotics (but not Hardware side) my humble opinion is that it is the easiest(software), durable and robust one (and probably cheapest) available.

When you have two finger grippers, you have to consider how wide they can open (if it is too narrow, usability suffer, too wide the mechanical complexity increases), how many joints you have (too many make them heavy/low durability/expensive), and the torque/force you can put on the fingers (too high it crush the object, too low it slips out. Also more force you want, more expensive the gripper becomes).

On top of that, on the software side: if you use a suction pad you only need to estimate _one point_ of the object to be picked, and can also ignore the "grasping" problem all together. For other grippers you have to estimate several points (two for a simple gripper) and this increase the complexity for both detection (labeling of data, sensitive to center of mass in the object, etc) and grasping

[ragebol]

The advantage of suctions grippers is that they are naturally compliant, and thus forgiving of positioning errors.

There's some cool looking combinations as well, Righthand Robotics makes grippers that retracts a suction cup into a set of fingers. It looks a bit like Xenomorph.