Forces and torque measurements in the interaction of kitchen-utensils with food during typical cooking tasks: Preliminary test and evaluation

The study of cooking tasks, such as grilling, is hindered by several adverse conditions for sensors, such as the proximity to humidity, fat, and heat. Still, robotics research could benefit from understanding the human control of forces and torques in important contact interactions of kitchen-utensils with food. This work presents a preliminary study on the dynamics of grilling tasks (i.e. food flipping movements). A spatula and kitchen-tweezers were instrumented to measure forces and torque in multiple directions. Furthermore, we designed an experimental setup to keep sensors distant from heat/humidity and to, simultaneously, hold the effects of grilling (stickiness/slipperiness) during the tasks execution and recording. This allowed a successful data collection of 1426 movements with the spatula (flipping hamburgers, chicken, zucchini and eggplant slices) and 660 movements with the tweezers (flipping zucchini and eggplant slices), performed by chefs and ordinary home cooks. Finally, we analyzed three dynamical characteristics of the tasks for the different food: bending force and torsion torque on the impact to unstick food, and maximum pinching with tweezers. We verified that bending on impact and maximum pinching are adjusted to the food by both chefs and home cooks.