US team develops robotic lake lander for planetary exploration

Dubbed TEX II, the vehicle could be used to explore the lakes of liquid hydrocarbon known to exist on Saturn’s largest moon, Titan.

TEX II is said to be highly modular and portable and was designed as a catamaran for enhanced stability, and to allow the various onboard sensors easy access to the surface and subsurface of the water, or other liquid, on which it is deployed.

It weighs about 100 pounds and its central raised deck can carry a 150-pound payload of computers, batteries and sensors. The twin hulls are 6ft long and set about 5ft apart.

Air-propellers mounted at the back of each hull are powered by electric motors that can switch rotational direction to drive TEX II backward or forward, which makes the craft highly agile.

The propellers are set as far apart as possible so they deliver maximum torque to the chassis during turning.

The shallow draft of the fortified Styrofoam hulls decreases perturbation in the water around TEX II, which minimises interference with subsurface telemetry from the onboard sensors. The entire chassis and sensor deck can be decoupled from the catamaran hulls and attached to an alternative propulsion system.

The Styrofoam hulls of TEX II are claimed to have a significant advantage over other hull types in that they can sustain hull damage without jeopardising buoyancy.

Robot hierachy

According to a statement, Fink envisions future planetary research being conducted by a hierarchy of intelligent, autonomous robots that could include satellites, airships or blimps, and a fleet of rovers and lake landers.

His vision is that an orbiting satellite would direct atmospheric blimps to scan potentially interesting areas of a planetary surface. The blimps would then order surface-based rovers and lake landers to investigate geological features in detail and collect samples in situ.

Fink wants them to investigate certain situations and environments, and then learn from those investigations so they can make increasingly intelligent choices about where to go and what to investigate next.

In its current configuration TEX II can be controlled from anywhere in the world via an internet connection and will soon be fully autonomous.

‘TEX II is ready to deploy on missions related to defence and security, such as harbour surveillance and clean-up operations of littoral munitions dumps and mines,’ Fink said. It is also ideal for search-and-rescue operations in oceans, lakes, and hazardous environments, as well as for environmental research projects.’

‘TEX II is currently fitted with onboard cameras and sonar that can penetrate up to 100m,’ Fink added. Other sensors could be added, he said, to detect pathogens, toxins, explosives, radiation, and so on.

Fink unveiled TEX II in a paper titled ‘Robotic lake lander test bed for autonomous surface and subsurface exploration of Titan lakes’, which he presented on 8 March at an aerospace conference organised by the Institute of Electrical and Electronics Engineers in Big Sky, Montana.