Table 1 Comparison of four categories of duct travelling robots with respect to desired mobility features
WTR | DuCTT | Wheeled robots | Expanding robots | |
|---|---|---|---|---|
Move horizontally | ✔ | ✔ | ✔ | ✔ |
Move vertically | ✔ | ✔ | ✗ | ✔ |
Turn right/left into a branch | ✔ | ✔ | ✔ | ✗ |
Turn up/down into a branch | ✔ | ✔ | ✗ | ✗ |
Narrow horizontal u-turn | ✔ | ✗ | ✔ | ✗ |
Narrow vertical u-turn | ✔ | ✗ | ✗ | ✗ |
Speed of 0.7 m/s or higher | ✔ | ✗ | ✔ | ✔ |
Move in an open plane | ✔ | ✗ | ✔ | ✔ |