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Taking inspiration from nature the NEMOdeep vehicle described in this paper is being developed as a laboratory demonstrator to showcase potential technologies to achieve small deep diving autonomous underwater vehicles. The design of the vehicle is a hybrid of conventional AUV components with engineered analogues of marine animal organs. The internal structure is comprised of a spine, ribs and sternum, which support a hydrodynamic fairing or ‘skin’. The ‘brain’ and actuators are developed using pressure tolerant electronics, negating the need for pressure vessels. The pressure tolerant electronics are surrounded by light mineral oil which transmits the hydrostatic pressure uniformly to the components while also providing buoyancy. The internal fluid is more compressible than seawater and the batteries and internal structure are less compressible than seawater: a ‘Buoyancy/Compressibility’ organ is being developed to passively maintain neutral buoyancy over the 0 to 6000m depth range.

Modern unmanned underwater vehicles generally use one of two methods for manoeuvring; thrusters or control surfaces. These control methods each have a limited range of speeds over which they can operate efficiently. Manoeuvring control is often separate from the propulsion system, increasing vehicle weight and drag. By comparison, many animals possess only one set of propulsors which is used for both propulsion and manoeuvring. There are many types of marine animal locomotion, aquatic flight stands out for having both high speed and very good manoeuvrability and is the focus of the present research. The investigation uses a combination of animal video motion analysis, mathematical modelling and experimentation. Video motion analysis was used to provide data on the actual motion made by a penguin wing during swimming motion. Of particular interest is the yaw motion of the wing, however the ability to accurately capture this axis of motion was hindered by the video quality. The mathematical modelling concentrated on the Blade Element Theory (BET). The model was used to assess the loads generated by the motion of a wing section. In additional to the hydrodynamic lift and drag forces, the BET model also modelled added mass forces and Kramer effect. However, the result the model still under predicted the thrust coefficient suggesting the thrust is supplemented by other hydrodynamic effects. The BET model was also used for analysis of three axis actuation where it found the yaw motion will reduce thrust coefficient. Finally a three axis experiment has been designed with inspiration from the motion observed from swimming penguins and the experiment will be used to validate the forces from the mathematical model.

Intelligent Mobility Platform with Active Spoke System (IMPASS) is a novel wheel-leg hybrid robot that can walk in unstructured environments by stretching in or out three independently actuated spokes of each wheel. This form of novel locomotion has the potential to combine the efficiency of a wheeled robot and the mobility of a legged robot. A highly mobile robot such as IMPASS could prove very valuable in applications where the terrain is complex and dangerous, such as search and rescue, reconnaissance, or anti-terror response. This video presents the experiments and findings of a variety of straight-line walking, transitions, and turning gaits. With the 1- 1 and 2-2 straight walking gaits, the robot can move forward stably but with different constraints. Unlike other wheeled vehicles which use Arckerman steering or differential steering, IMPASS can implement novel turning gaits even though the left and right hubs rotate with the same angular velocity. Steady state turning gait is demonstrated with skew transitions. Additionally, a free form gait is demonstrated using joystick control with interesting observations.