Delicate manipulation of various foods for a meal assistant robot with an integrated spoon-chopstick mechanism: A force-sensing module and force control

Eating is one of the most frequent and important activities in daily life. However, a significant number of disabled and elderly people complete this activity with assistance from other people such as family members or caregivers. To solve this issue, various types of meal-assistance robots (MARs) are being actively developed. Most of the existing MARs are equipped with a spoon or fork owing to ease of operation and the culture in which these MARs are used. In Asian cultures, in addition to spoons and forks, chopsticks are widely used. Moreover, it is considered natural and common to use a spoon and chopsticks together. For this reason, our research consortium is developing a MAR equipped with an integrated spoon and chopstick mechanism (ISCM). In this study, to realize the delicate manipulation of various foods, we propose a compact force-sensing module that can be seamlessly integrated into the MAR equipped with ISCM. A force-control algorithm is implemented using the proposed module to verify whether various foodstuffs can be manipulated using chopsticks. The results of a series of experiments indicate that the proposed mechanism is feasible and effective.