Abstract: A wearable air purification system having a wearable support configured to be supported on a user's head. The wearable support is attached to an air delivery mask which delivers a flow of air to an air delivery region. A motor for driving the flow of air to the air delivery region is mounted on the wearable support, or on the air delivery mask, and an air filter for purifying the flow of air is mounted on the wearable support, or on the air delivery mask. Each end of the air delivery mask is moveably connected to the wearable support so that the wearable support is able move with respect to the air delivery mask from a deployed position to a stowed position. The volume envelope of the wearable air purification system is larger in the deployed position than in the stowed position.

Abstract: A wearable air purifier including a headgear; an air purifier assembly, the air purifier assembly configured to generate a filtered airflow from an outlet aperture thereof; and a nozzle assembly connected to the headgear by a hinge assembly. The nozzle assembly includes an inlet aperture for receiving the filtered airflow from the outlet aperture of the air purifier assembly and an air outlet for emitting the filtered airflow from the nozzle assembly. The hinge assembly is configured such that the nozzle assembly is movable relative to the headgear between first and second configurations, filtered airflow is emitted from the air outlet in the first configuration and filtered airflow is not emitted from the air outlet in the second configuration.

Abstract: A method of deploying autonomous underwater vehicles (AUVs), the method comprising loading the AUVs into a deployment device; submerging the deployment device containing the AUVs after the AUVs have been loaded into the deployment device; towing the submerged deployment device containing the AUVs with a surface vessel; deploying the AUVs from the submerged deployment device as it is towed by the surface vessel; and operating a thruster of each AUV after it has been deployed so that it moves away from the submerged deployment device. A method of retrieving autonomous underwater vehicles (AUVs) is also disclosed, the method comprising towing a submerged retrieval device with a surface vessel; loading the AUVs into the submerged retrieval device as it is towed by the surface vessel; and after the AUVs have been loaded into the submerged retrieval device, lifting the submerged retrieval device containing the AUVs out of the water and onto the surface vessel.

Abstract: A method assesses the beam profile of a light beam of a non-contact tool setting apparatus, the apparatus including a transmitter for emitting the light beam and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The apparatus is mounted to a machine tool having a spindle that is moveable relative to the non-contact tool setting apparatus. The method includes loading an object having an edge into the spindle of the machine tool and using the machine tool to move the spindle relative to the apparatus so that the edge of the object passes through the light beam. The beam profile of the light beam is then determined using the beam intensity signal generated at a plurality of positions during the step (ii) of moving the edge of the object through the light beam.

Abstract: A method for tool measurement using a non-contact tool setting apparatus mounted to a machine tool, which includes a transmitter for emitting a light beam having a beam width and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The method is for measuring a tool having a nominal tool diameter less than the beam width so fully inserting the tool feature into the light beam would only partially occlude the beam. The method includes moving the tool through the beam thereby causing a change in the intensity signal and generating a trigger signal when the intensity signal crosses a trigger threshold. The tool size is derived using the trigger signal generated. Also, a step of applying a tool length correction that accounts for the nominal tool diameter of the tool being less than the beam width.

Abstract: An injector comprises at least one injection nozzle, a dosing system to provide a dosed flow of reducing agent to the at least one or each injection nozzle, and an injection line fluidically connecting the dosing system to the at least one or each injection nozzle. The injection line comprises an upstream pipe fluidically connected to the dosing system, at least one downstream pipe fluidically connected to a respective injection nozzle, and at least one anti-backflow device to avoid or minimize fluidic flow from the at least one or each downstream pipe toward the upstream pipe.

Abstract: A method of deploying autonomous underwater vehicles (AUVs), the method comprising loading the AUVs into a deployment device; submerging the deployment device containing the AUVs after the AUVs have been loaded into the deployment device; towing the submerged deployment device containing the AUVs with a surface vessel; deploying the AUVs from the submerged deployment device as it is towed by the surface vessel; and operating a thruster of each AUV after it has been deployed so that it moves away from the submerged deployment device. A method of retrieving autonomous underwater vehicles (AUVs) is also disclosed, the method comprising towing a submerged retrieval device with a surface vessel; loading the AUVs into the submerged retrieval device as it is towed by the surface vessel; and after the AUVs have been loaded into the submerged retrieval device, lifting the submerged retrieval device containing the AUVs out of the water and onto the surface vessel.

Abstract: A method of deploying autonomous underwater vehicles (AUVs), the method comprising loading the AUVs into a deployment device; submerging the deployment device containing the AUVs after the AUVs have been loaded into the deployment device; towing the submerged deployment device containing the AUVs with a surface vessel; deploying the AUVs from the submerged deployment device as it is towed by the surface vessel; and operating a thruster of each AUV after it has been deployed so that it moves away from the submerged deployment device. A method of retrieving autonomous underwater vehicles (AUVs) is also disclosed, the method comprising towing a submerged retrieval device with a surface vessel; loading the AUVs into the submerged retrieval device as it is towed by the surface vessel; and after the AUVs have been loaded into the submerged retrieval device, lifting the submerged retrieval device containing the AUVs out of the water and onto the surface vessel.

Abstract: A method for tool measurement using a non-contact tool setting apparatus mounted to a machine tool, which includes a transmitter for emitting a light beam having a beam width and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The method is for measuring a tool having a nominal tool diameter less than the beam width so fully inserting the tool feature into the light beam would only partially occlude the beam. The method includes moving the tool through the beam thereby causing a change in the intensity signal and generating a trigger signal when the intensity signal crosses a trigger threshold. The tool size is derived using the trigger signal generated. Also, a step of applying a tool length correction that accounts for the nominal tool diameter of the tool being less than the beam width.

Abstract: A method assesses the beam profile of a light beam of a non-contact tool setting apparatus, the apparatus including a transmitter for emitting the light beam and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The apparatus is mounted to a machine tool having a spindle that is moveable relative to the non-contact tool setting apparatus. The method includes loading an object having an edge into the spindle of the machine tool and using the machine tool to move the spindle relative to the apparatus so that the edge of the object passes through the light beam. The beam profile of the light beam is then determined using the beam intensity signal generated at a plurality of positions during the step (ii) of moving the edge of the object through the light beam.

Abstract: An injector comprises at least one injection nozzle, a dosing system to provide a dosed flow of reducing agent to the at least one or each injection nozzle, and an injection line fluidically connecting the dosing system to the at least one or each injection nozzle. The injection line comprises an upstream pipe fluidically connected to the dosing system, at least one downstream pipe fluidically connected to a respective injection nozzle, and at least one anti-backflow device to avoid or minimize fluidic flow from the at least one or each downstream pipe toward the upstream pipe.

Abstract: A method of obtaining data with a sensor of an autonomous underwater vehicle (AUV), the AUV comprising a bladder which contains a gas and is exposed to ambient water pressure. A downward thrust force is generated which causes the AUV to descend through a body of water, wherein the bladder contracts as the AUV descends due to an associated increase in the ambient water pressure, the contraction of the bladder causing the gas to compress and the AUV to become negatively buoyant. Next the AUV lands on a bed of the body of water. After the AUV has landed on the bed, the sensor is operated to obtain data with the AUV stationary and negatively buoyant and a weight of the AUV supported by the bed.

Abstract: An underwater vehicle comprising: port and starboard thrusters spaced apart in a port- starboard direction, each thruster being oriented to generate a thrust force in a fore-aft direction perpendicular to the port-starboard direction; a vertical thruster which is oriented to generate a thrust force substantially perpendicular to the fore-aft and port- starboard directions; port, starboard and vertical ducts which contain the port, starboard and vertical thrusters respectively, each duct providing a channel for water to flow through its respective thruster; and a moving mass which can be moved relative to the thrusters in the fore-aft direction to control a pitch of the underwater vehicle.

Abstract: A submersible device (2) for deploying or retrieving autonomous underwater vehicles (AUVs), the submersible device comprising: two or more platforms (130) arranged in a stack (3a, 3b), wherein each platform is configured to carry two or more of the AUVs; a port (300, 310); and a transfer mechanism (200) comprising a transfer device (210) arranged to load or unload the AUVs onto or from the platforms, and an actuator arranged to move the transfer device between the platforms and the port in order to transfer the AUVs between the platforms and the port.

Abstract: A method of obtaining data with a sensor of an autonomous underwater vehicle (AUV), the AUV comprising a bladder which contains a gas and is exposed to ambient water pressure. A downward thrust force is generated which causes the AUV to descend through a body of water, wherein the bladder contracts as the AUV descends due to an associated increase in the ambient water pressure, the contraction of the bladder causing the gas to compress and the AUV to become negatively buoyant. Next the AUV lands on a bed of the body of water. After the AUV has landed on the bed, the sensor is operated to obtain data with the AUV stationary and negatively buoyant and a weight of the AUV supported by the bed.

Abstract: A method of deploying autonomous underwater vehicles (AUVs), the method comprising loading the AUVs into a deployment device; submerging the deployment device containing the AUVs after the AUVs have been loaded into the deployment device; towing the submerged deployment device containing the AUVs with a surface vessel; deploying the AUVs from the submerged deployment device as it is towed by the surface vessel; and operating a thruster of each AUV after it has been deployed so that it moves away from the submerged deployment device. A method of retrieving autonomous underwater vehicles (AUVs) is also disclosed, the method comprising towing a submerged retrieval device with a surface vessel; loading the AUVs into the submerged retrieval device as it is towed by the surface vessel; and after the AUVs have been loaded into the submerged retrieval device, lifting the submerged retrieval device containing the AUVs out of the water and onto the surface vessel.

Abstract: A submersible device (2) for deploying or retrieving autonomous underwater vehicles (AUVs), the submersible device comprising: two or more platforms (130) arranged in a stack (3a, 3b), wherein each platform is configured to carry two or more of the AUVs; a port (300, 310); and a transfer mechanism (200) comprising a transfer device (210) arranged to load or unload the AUVs onto or from the platforms, and an actuator arranged to move the transfer device between the platforms and the port in order to transfer the AUVs between the platforms and the port.

Abstract: An underwater vehicle comprising: port and starboard thrusters spaced apart in a port-starboard direction, each thruster being oriented to generate a thrust force in a fore-aft direction perpendicular to the port-starboard direction; a vertical thruster which is oriented to generate a thrust force substantially perpendicular to the fore-aft and port-starboard directions; port, starboard and vertical ducts which contain the port, starboard and vertical thrusters respectively, each duct providing a channel for water to flow through its respective thruster; and a moving mass which can be moved relative to the thrusters in the fore-aft direction to control a pitch of the underwater vehicle.

Abstract: A frequency tuneable laser device includes a cavity mode selector and a cavity tuning arrangement. The cavity mode selector has a frequency response with a selection feature that is alignable in frequency with a selected cavity mode of the laser device. The cavity tuning arrangement includes a plurality of reflective elements arranged in optical series, and is used to adjust the effective optical path length of the laser cavity to move the cavity modes in frequency. The laser device further includes making the cavity mode selector and the cavity tuning arrangement perform a simultaneous coordinated movement such that respective frequencies of the selection feature and the selected cavity mode vary with substantially the same dependence on a parameter characterizing the simultaneous coordinated movement. For example, a periscope with a co-rotating etalon can be used to provide mode hop free tuning of the laser device.

Abstract: A frequency tuneable laser device includes a cavity mode selector and a cavity tuning arrangement. The cavity mode selector has a frequency response with a selection feature that is alignable in frequency with a selected cavity mode of the laser device. The cavity tuning arrangement includes a plurality of reflective elements arranged in optical series, and is used to adjust the effective optical path length of the laser cavity to move the cavity modes in frequency. The laser device further includes making the cavity mode selector and the cavity tuning arrangement perform a simultaneous coordinated movement such that respective frequencies of the selection feature and the selected cavity mode vary with substantially the same dependence on a parameter characterising the simultaneous coordinated movement. For example, a periscope with a co-rotating etalon can be used to provide mode hop free tuning of the laser device.