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During laparoscopic grasping, tissue damage may occur due to use of excessive grasp forces and tissue slippage, whereas in barehanded grasping, humans control their grasp to prevent slippage and use of excessive force (safe grasp). This study investigates the differences in grasp control during barehanded and laparoscopic lifts. Ten novices performed lifts in order to compare pinch forces under four conditions: barehanded; using tweezers; a low-efficient grasper; and a high-efficient grasper. Results showed that participants increased their pinch force significantly later during a barehanded lift (at a pull-force level of 2.63 N) than when lifting laparoscopically (from pull-force levels of 0.77 to 1.08 N). In barehanded lifts all participants could accomplish a safe grasp, whereas in laparoscopic lifts excessive force (up to 7.9 N) and slippage (up to 38% of the trials) occurred frequently. For novices, it can be concluded that force feedback (additional to the hand-tool interface), as in skin-tissue contact, is a prerequisite to maintain a safe grasp. Much is known about grasp control during barehanded object manipulation, especially the control of pinch forces to changing loading, whereas little is known about force perception and grasp control during tool usage. This knowledge is a prerequisite for the ergonomic design of tools that are used to manipulate objects.

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Background: In order to develop new and better laparoscopic bowel instruments, which reduces patient risks, the opinions and experience that surgeons have with current laparoscopic bowel grasper haptics is important. In this study we explored this by means of a questionnaire. Method: A total of 386 online- questionnaires, were sent to laparoscopic surgeons working in European hospitals. They were all members of the European Association of Endoscopic Surgery and perform laparoscopic obesities or bowel surgery. Surgeons where divided into different age and experience groups. Results: A total of 174 completely filled out forms were analyzed. In total, 16% of the surgeons cannot prevent damage when they pinch too hard, although they (10%) might have seen or felt it. Seven percent of the respondents were not able to see or feel tissue slippage. Whereas 31% can see or feel slippage they cannot do anything to prevent it. Overall, most of the respondents would appreciate technical changes in the laparoscopic bowel graspers to reduce tissue damage. Of all the respondents, 79% maintain that it is necessary to have a new laparoscopic grasper with augmented feedback. The majority of the respondents (77%) would like to have tactile feedback as an indication of the level of pinch force. There are not many differences in the opinions of surgeons at different skill levels. Conclusion: From the results of the questionnaire and the other comments made by respondents it is evident that research and developments in the field of new laparoscopic graspers should continue

In this article a haptic tool for industrial designers is presented. The tool should aid them in material selection for product experience and fit in an advanced design studio: the Tangible Virtual Reality environment. A study of related work suggests that six touch sensations are essential in this context. A solution idea for multi-sensation feedback was developed and its intended behavior and functionalities defined. A first concept combines two of the relevant sensations: texture and warmth, the former displayed by a piezo-driven pin array and the latter by a peltier element acting as a heat pump. A simple experiment — matching displayed stimuli to real materials — was conducted to prove the feasibility of the concept. Experimental results confirm that the prototype gives the impression of a certain surface, but the absence of four relevant sensations limits the experience’s realism. However promising, these results confirm the desirability of further integration of touch sensations in one device.