Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Controlling robots that search for Mars life

12.07.2006
As part of ESA's ambitious, long-term Aurora exploration programme, ExoMars will search for traces of life on Mars. The mission requires entirely new technologies for self-controlled robots, built-in autonomy and cutting-edge visual terrain sensors.

The fourth decade of this century could see Europe participating in a manned mission to Mars in what would be one of humanity's grandest space expeditions ever.

Aurora is ESA's programme aimed at the long-term robotic and human exploration of the Solar System, with Mars and the Moon as the main targets.

A human mission to the Red Planet would be a major, multi-year undertaking requiring fantastic, entirely new capabilities such as automated cargo vessels, prepositioned supplies and tools, and communication and navigation satellites in Mars orbit similar to Earth's current GPS systems.

Scientists and engineers are already working on ESA's first robotic 'precursor' mission, ExoMars, due for launch around 2011.

ExoMars will explore the biological environment on Mars in preparation for further robotic and, later, human activity. Data from the mission will also provide invaluable input for broader studies of exobiology – the search for life on other planets.

The main element of the mission is a wheeled, robotic rover vehicle, similar in concept to NASA's current Mars Rover mission, but having different scientific objectives and improved capabilities.

ExoMars: a wheeled rover delivered in a dramatic direct approach

The mission will likely consist of a carrier spacecraft, a descent module, some sort of landing system, and the surface rover, and the mission profile is likely to include a dramatic direct approach to Mars, with the carrier spacecraft discarded after the rover detaches itself for descent to the surface.

The rover will use solar arrays to generate electricity, and will travel over the rocky orange-red surface of Mars, transporting an up to 12-kilogram experimental payload including a first-ever lightweight drilling system, as well as a sampling and handling device, and a set of scientific instruments to search for signs of past or present life.

Due to distance time-lag and complexity, ExoMars will self-navigate using 'smart' electro-optics to visually sense and interpret the surrounding terrain and will be capable of operating autonomously using intelligent onboard software.

Automated control a major advance

This automated mode of operation is a major advance for ESA, long used to controlling spacecraft directly using human controllers. And not only will the rover's onboard control systems be new.

"ExoMars will require entirely new techniques and technology for several aspects of the Earth-based rover control system, not just an upgrade of what we have today," says Mike McKay, a senior spacecraft controller and Mars expert based at ESOC, ESA's Spacecraft Operations Centre, in Darmstadt, Germany.

ESA spacecraft have long had some ability to make independent decisions based on external influences. For example, onboard instruments will automatically shut down if solar radiation suddenly rises, or the spacecraft will automatically switch into a diagnostic 'safe mode' if anything goes wrong. But for the most part, lengthy instructions still must be pre-programmed by mission controllers on Earth and sent up for later, step-by-step, execution.

And ESA controllers have never before operated a mission that moved about on the surface of another body; Huygens – which touched down successfully on Titan in 2005 – was an atmospheric probe and not a lander, although it functioned briefly after reaching Titan's surface.

Robotic task: traverse kilometres of terrain in search of life

In one typical example of the rover's autonomous operation, ground controllers might radio up a high-level command telling it to drive to a scientifically interesting spot anywhere from 500 to 2000 metres away and conduct science operations, such as drilling beneath the surface to sample soil for life signs. But the vehicle would handle the details of the move on its own.

It would survey the ground with a 3D camera, create a digital terrain model, verify its present location, run internal simulations and then make an autonomous decision on the best path to follow, based on obstacles, the rover's current status and risk/resource considerations.

"Then it will drive itself to the target. We expect its target accuracy to be within one-half metre over a traverse of 20 metres," says Bob Chesson, head of the Human Spaceflight and Exploration Operations Department in ESA’s Operations directorate.

ExoMars profits from current robotic explorers

As the next generation of robot, ExoMars will profit from lessons learned from the current generation, including NASA's Mars Explorer Rover (MER) mission, including the need for improved locomotion ability, improved local terrain sensing – to avoid ground slippage – and the need for higher autonomy to transverse cluttered terrain.

Earlier missions, such as NASA's Sojourner rover in 1997, used an even less sophisticated approach, with Sojourner sensing its surrounding terrain, but then with all processing and path planning being done on Earth. "We're not shy in trying to learn from the experiences of our sister agencies," says Chesson.

Innovative ground control to enable autonomous functioning

For ExoMars, the controllers on Earth would most likely be located in a 'rover dedicated control room', similar in concept to the dedicated control rooms (DCR) that ESA now sets up for individual missions that orbit planets.

ESOC will serve as the overall mission operations control centre (MOCC), controlling the launch and early orbit phase (LEOP), the cruise to Mars, the separation and landing of the Descent Module and the Rover egress, with management of rover surface operations likely to be conducted from the Rover Operation Centre located at ALTEC, the Advanced Logistic Technology Engineering Center, in Turin, Italy.

"The design of the rover ground control system, or ground segment, depends on the scientific and operational goals of the rover, which are not yet final, so the ground system is still evolving," says Chesson. "In principle, the basic telemetry and telecommand functions would be essentially the same as now, but it will have significantly new capabilities to allow for the rover's autonomous functioning."

The ground control system will at least require computing facilities to enable high-level mission planning tools and to allow monitoring of the rover's digital terrain and 3D modelling, ground path and trajectory planning, on-ground simulation and tight integration with the payload control and scientific operations.

"Classic direct control methods just won't work when we operate on the surface of Mars in an unstructured environment and with a significant signal time delay, says Reinhold Bertrand," a planning engineer and robotics expert at ESOC. "ExoMars will require a change in culture; we have to 'let the child walk on its own' while we develop a truly interdisciplinary operations concept."

Jocelyne Landeau-Constantin | alfa
Further information:
http://www.esa.int
http://www.esa.int/spacecraftops/ESOC-Article-fullArticle_par-40_1151301927523.html

More articles from Physics and Astronomy:

nachricht First Juno science results supported by University of Leicester's Jupiter 'forecast'
26.05.2017 | University of Leicester

nachricht Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>