A statistical review of industrial robotic grippers

With the recent introduction of ambitious industrial strategies such as Horizon 2020 and Industry 4.0, a massive focus has been placed on the development of an efficient robotic workforce. Amongst all the operations robotic systems can take care of, handling remains a preferred choice due to a combination of factors including its often repetitive nature and low skill requirement. The associated demand for grasping tools has led to an ever increasing market for manipulation end-of-arm tooling from which a handful of industry giants have emerged. Based on data publicly accessible from the catalogs of several well-known companies, this paper aims at presenting a review on the characteristics of pneumatic, parallel, two-finger, industrial grippers. Included in the specifications under scrutiny in this paper are: stroke, force, weight, as well as a performance index referred to as the C-factor. This last index is a combination of three of the aforementioned characteristics and has been proposed in the literature as a measure of the efficiency that a gripper is capable of reaching. As will be shown, by analyzing hundreds of specifications it appears that, indeed, the range of C-factors of the grippers built by one company can be often consistently different from these of competitors. Furthermore, an important bias for certain typical specifications can be observed in most of the grippers which seems at odd with the requirement of modern robotic systems. This latter remark will open up a closing discussion proposed in the last part of this paper on the future evolution of grippers based on emerging new products.