Marine Robotics for Deep-Sea Specimen Collection: A Systematic Review of Underwater Grippers

Abstract

The collection of delicate deep-sea specimens of biological interest with remotely operated vehicle (ROV) industrial grippers and tools is a long and expensive procedure. Industrial grippers were originally designed for heavy manipulation tasks, while sampling specimens requires dexterity and precision. We describe the grippers and tools commonly used in underwater sampling for scientific purposes, systematically review the state of the art of research in underwater gripping technologies, and identify design trends. We discuss the possibility of executing typical manipulations of sampling procedures with commonly used grippers and research prototypes. Our results indicate that commonly used grippers ensure that the basic actions either of gripping or caging are possible, and their functionality is extended by holding proper tools. Moreover, the approach of the research status seems to have changed its focus in recent years: from the demonstration of the validity of a specific technology (actuation, transmission, sensing) for marine applications, to the solution of specific needs of underwater manipulation. Finally, we summarize the environmental and operational requirements that should be considered in the design of an underwater gripper.

Marine Robotics for Deep-Sea Specimen Collection: A Taxonomy of Underwater Manipulative Actions

“…As pointed out in [22], research prototypes of grippers successfully demonstrated cnidarian collection. Dendronephthya and scleractinians were collected with the bellowtype actuator, and an alcyonacean whip coral with the boa-type [29,30]; both grippers implemented a scissor-like cutting tool.…”

“…This process required two steps, the results of which are reported in the present series of two papers. The first step consisted of a thorough analysis of the commercially available gripper technologies currently used for underwater collection of scientific samples, and a systematic review of the research status of underwater grippers, which we performed in [22]. As a second step, in this paper, we investigated the manipulative actions needed in underwater manipulation for the collection of scientific samples.…”

“…Indeed, suction procedures, or the use of nets and traps, are mentioned in the literature as sampling methods for cephalopods [33,34]. Among research grippers presented in [22], shell collection was reported with the soft OBSS gripper [35], the Tshingua University cage gripper [36] was able to collect some scallops, and collection of Oegospina sp. and Stigmatoteuthis sp.…”

“…• "B" if the tool is the main (see Table 2) of the basic action. In [22], we compared the atomic manipulations identified here from researcher evidence (Table 3, in black) with gripper technologies, to evaluate the possibility of action for each technology. Some of the grippers analyzed in [22] were tested for atomic manipulations that were not reported here by researchers; those atomic manipulations were subsequently added to our taxonomy and are reported in red in Table 3.…”

“…The arrows indicate possible combinations of atomic manipulations that build potentially feasible manipulation sequences. This figure does not include the atomic manipulations we added to our taxonomy from the results of [22], since those atomic actions were demonstrated while testing research prototype grippers, and those testing procedures did not necessarily consider the entire procedure of sampling a marine organism. preferred to limit the description of the manipulative sequences to procedures that are more consolidated within the common practice of sampling marine organisms.…”