Table 1.

Selection of objects for experimentation. Each object has been assigned a number to facilitate the subsequent display of results (first column). The “Dimensions” column shows the significant dimensions of each object, and the “Weight” column shows the weight of the objects used in the experiments. In the last column “Relevant Aspects”, the aspects that differentiate each object from the others are highlighted.

ID	Object	Dimensions	Weight	Relevant Aspects
1	Tennis ball	70 mm diameter	57.6 g	Quite rigid and with a rough surface
2	Screen Cleaner	80 mm diameter 30 mm thickness	12.8 g	Considerably soft and deformable
3	Vaseline container	80 mm diameter 50 mm height	147 g	Very smooth surface
4	Metallic container	85 × 50 × 30 mm	47.9 g	Prismatic form with some irregularities, smooth surface
5	Nut	35 mm diameter 45 mm height	14.4 g	Very small and lightweight
6	Rock	25 × 15 × 10 mm	12.9 g	The smallest object of the experiment
7	Tomato	90 mm diameter 70 mm height	229.6 g	The heaviest object of the experiment
8	Egg	50 mm diameter 65 mm height	71 g	Hard but very fragile
9	Glue stick	25 mm diameter 100 mm height	19.6 g	Svelte with irregularities at the ends
10	Dish sponge	105 × 80 × 25 mm	10.2 g	Considerably soft and deformable with a slightly stiffer surface
11	Broccoli	90 mm diameter 120 mm height	130.4 g	Irregular object that should not be deformed
12	Candy box	60 × 35 × 15 mm	7.9 g	Little gripping surface