Experimental measurement on movement of spiral-type capsule endoscope

Figures & data

Figure 1 Poles of magnet ring (A) and fabricated capsules (B).

Abbreviations: cap, capsule; N, north; S, south.

Table 1 Parameters of magnet rings

Identifier	Length (mm)	Outer diameter (mm)	Inner diameter (mm)	Maximum magnetic flux intensity of two poles (mT)
ring1	18	12	10	247
ring2	15	15	12	340

Table 2 Parameters of dummy capsules

Identifier	Total length (mm)	Diameter of spiral line (mm)	Magnet ring identifier
cap1	28	1	ring1
cap2	28	2	ring1
cap3	26	1	ring2
cap4	26	2	ring2

Abbreviation: cap, capsule.

Figure 2 General view of magnetic driving instrument.

Figure 3 The torque measurement setup.

Abbreviations: PC, personal computer; CB-204, cable-204.

Figure 4 The torque measurement.

Table 3 Torque measurements

Distance (mm)	Torque (gf · m)
15	4.75
20	3.20
25	2.07
30	0.93
35	0.33
40	0.14
45	0.09
50	0.001

Figure 5 Measurement setup of rotation synchronization of capsule and stepper motor.

Figure 6 The measurement of rotation synchronization of capsule and stepper motor.

Abbreviations: rpm, revolutions per minute; cap, capsule.

Figure 7 Measurement setup of translational motion time.

Figure 8 Translational velocity of capsules under different rotation speed.

Abbreviations: rpm, revolutions per minute; cap, capsule.

Table 4 Translational motion time

Rotational speed of motor (rpm)	216	177	150	129	117	99	78	57	36	24	9
Minimum time (seconds)
cap1	32	36	33	30	37	39	35	42	58	88	*
cap2	33	35	41	46	45	52	72	70	79	132	*
cap3	36	51	31	42	56	41	68	65	83	85	*
cap4	27	36	40	34	43	45	43	49	58	80	*

Note:

* Indicates that the capsule hardly moved forward at the rotational speed of 9 rpm.

Abbreviations: rpm, revolutions per minute; cap, capsule.