The present disclosure provides a cleaning device, including a cleaning device body, a drive mechanism, a filtering mechanism, a liquid inlet portion, a liquid outlet portion, and a mode switching member. The drive mechanism is configured to generate a suction force to form a first water flow path with the liquid inlet portion, the filtering mechanism, and the liquid outlet portion. The mode switching member is configured to allow the cleaning device to be switched between a first motion state and a third motion state. Switching of the cleaning device between the first motion state and the third motion state includes switching of a second motion state. The cleaning device performs underwater cleaning in the first motion state, cleans a pool wall or a waterline in the second motion state, and performs water surface cleaning in the third motion state.

A biomimetic turtle device includes a trunk unit, a limb unit and a control unit. The control unit includes a water depth sensor which detects water depth where the biomimetic turtle device is, and a circuit module which receives the signal from the water depth sensor and determines if the biomimetic turtle device is at a target water depth position, wherein a driving mechanism or a weight adjusting mechanism is operated if the biomimetic turtle device is not at the target water depth position to vary the volume or weight of the trunk unit so as to adjust density of the trunk unit to thereby adjust a water depth position of the biomimetic turtle device.

A biomimetic turtle device includes a trunk unit, a limb unit and a control unit. The control unit includes a water depth sensor which detects water depth where the biomimetic turtle device is, and a circuit module which receives the signal from the water depth sensor and determines if the biomimetic turtle device is at a target water depth position, wherein a driving mechanism or a weight adjusting mechanism is operated if the biomimetic turtle device is not at the target water depth position to vary the volume or weight of the trunk unit so as to adjust density of the trunk unit to thereby adjust a water depth position of the biomimetic turtle device.

A marine seismic data acquisition system and method of conducting a marine seismic survey are disclosed. The system incorporates one or more surface vessels, and a plurality of autonomous nodes for acquiring seismic data at one or more seabed locations. Each node comprises a USBL, SSBL or SBL transducer and USBL, SSBL or SBL acoustic modem. A first acoustic positioning system is operable between one of the surface vessels and the nodes, the first acoustic positioning system being a USBL, SSBL or SBL system. Each node of the plurality of autonomous nodes has a USBL, SSBL or SBL beacon address, with respective groups of nodes having the same beacon address. The nodes are configured such that no two nodes with the same beacon address can actively communicate over an associated USBL, SSBL or SBL modem at the same time.

A marine seismic data acquisition system and method of conducting a marine seismic survey are disclosed. The system incorporates one or more surface vessels, and a plurality of autonomous nodes for acquiring seismic data at one or more seabed locations. Each node comprises a USBL, SSBL or SBL transducer and USBL, SSBL or SBL acoustic modem. A first acoustic positioning system is operable between one of the surface vessels and the nodes, the first acoustic positioning system being a USBL, SSBL or SBL system. Each node of the plurality of autonomous nodes has a USBL, SSBL or SBL beacon address, with respective groups of nodes having the same beacon address. The nodes are configured such that no two nodes with the same beacon address can actively communicate over an associated USBL, SSBL or SBL modem at the same time.