From the earth to the moon (Events Science stories)

Perhaps in this world no one is as weird as Bill Stone: Explore the deepest caves in the world to train and prepare for your journey into space.

Stone is not an astronaut, he is a cave explorer who has explored the deepest and most dangerous caves on Earth. He wanted to prove that the cave was the best training place for space exploration.

Robot DepthX

With NASA's $ 5 million support budget, Stone is developing a robot called DepthX, which could become the most advanced self-propelled underwater vehicle ever. DepthX is a cave exploration robot, capable of navigating and moving in tight conditions and many obstacles. DepthX's mission is in theory to look for life on Saturn's Europa moon. Even Stone didn't dare to believe in this almost impossible task.

This month, DepthX will be field tested for the first time, in the world's deepest cave Zacatón Cenote in Mexico. To achieve the ambition to conquer the universe, Stone needs to impress strongly with wealthy investors who are interested in the space universe. Therefore, this test must be monumental and successful. Moreover, at the age of 54, Stone didn't have much time left.

Let's compare DepthX with the two self-driving vehicles currently exploring Mars, Spirit and Opportunity, we will see the difficult task of the Stone group. Although they are very successful at collecting data and images, these two self-driving cars are still extremely sophisticated remote control vehicles. Ground control personnel will instruct Spirit and Opportunity to move based on the surrounding landscape images. DepthX meanwhile is a fully self-propelled vehicle. It will be released into a new environment, and have to figure out where it is, where to go and what to do.

Many different technologies are combined to create the DepthX self-propelled vehicle capable of mapping and detecting life. (Photo: Popsci)

Basically, DepthX is a giant sphere. Armed with 54 ultrasonic sensors, DepthX will collect data from thousands of ultrasonic waves every minute to create a detailed picture of the surrounding environment. DepthX not only draws a three-dimensional map of the surrounding landscape, but also determines its position in this environment, using an inertial guide, accelerometer, depth gauge and Other sensors for positioning. All of these devices constitute the Simultaneous Localization and Mapping (SLAM) unit.

This is the first test of three-dimensional SLAM. Autonomous vehicles today have a relatively narrow view and can only see ahead. DepthX is a cave exploration robot that can meet obstacles from any direction, so it has to have a comprehensive perspective.

Dream

From an early age, Stone dreamed of flying into space. In 1989, Stone entered the last 60 people out of the 10,000 applicants to join the NASA astronaut team.

In all physical, psychological and emotional tests, Stone ranks first. He was then called in for an interview before a board of former astronauts. When Guy Bluford asked him if he had any regrets in his life, Stone replied: "I want $ 2 billion to send a private expedition to the Moon."

During the past 10 years, Stone has become a scholar of the universe. His daily work is an auto technologist at the National Institute of Standards and Technology. In his spare time, he writes scientific articles such as life-support equipment, jet propulsion and spacecraft design. His technical genius and passion for space are well known. In 1982, he was invited to a congressional assembly to review existing space station projects, and then a federal government committee to design a private space station.

Equipped with 54 ultrasonic sensors, Bill Stone's self-propelled vehicle is a giant sphere that can create 3-D maps of the surrounding landscape. Maybe a similar robot will one day search for extraterrestrial life in the icy depths of Europa, a moon of Saturn.
Stone also wants to explore space: he is planning to lead a crew to the moon with private funding.

However, despite his erudite knowledge, Stone's opinion before the astronaut council showed pride and lack of restraint. Don Puddy, a senior specialist at the Johnson Space Center, told Stone: "It is unlikely that NASA will ever return to the Moon."

Stone felt every hope and dream for many years collapse. He was laid off and did not get upset. He said the agency's expedition department lacked the courage. With the help of a number of scientists at NASA, he himself sought to contribute to the discovery of strange lands.

Planet Europa

Since the Voyage 1 spacecraft orbited Jupiter in 1979, the home

From the deep pit to the sky

Shackleton crater is more than 1km deep, and horizontally more than 10km, mostly immersed in eternal darkness. Meteors often collide with the Moon and in Shackleton's deep bottom can accumulate thick layers of ice.

In the universe, ice is more precious than gold. Scientists can thaw to get drinking water, extract oxygen to breathe and use oxygen in combination with hydrogen as fuel for rockets. Stone wants to go further. According to his calculations, it is possible to transport ice from the Moon to space stations outside Earth's orbit for sale.

The biggest obstacle of space travel is that it takes a huge amount of fuel to escape the gravity of the Earth. But if a fuel station on the Moon could be set up, the cost of sending space ships could be reduced by 75%. Stone estimates that in just a few years, a base on the Moon could make $ 1 billion in revenue a year.

To equip his cave expeditions, Stone has gathered groups of comrades more than 100 people and has found millions of dollars in funding. In order to survive many weeks in dangerous, strange, and often airless environments, Stone has to face challenges similar to those of astronauts and has made equipment. Complicated support for expedition work.

Because underground caves are often submerged, Stone designed a vaporizer that can recycle exhaled carbonic gas for reuse so that divers can live more than 24 hours underwater. This type of vapor can completely be adjusted for use in outer space. There are caves that do not have any water at all. Stone is making a device that can recycle urine into potable water, which is very useful when landing on Shackleton for the first time.

In the cave as well as on the Moon, cannot rely on outside help. The explorer has to manage himself. The things Stone gathered from cave expeditions did not represent what he would do but how he would do this.

Although NASA rejected all his suggestions, Stone was not discouraged. He hopes private investors will be willing to shell out funding for his project. His chances are actually lower than that of winning the Powerball American lottery, but he still hopes that one day, it will be enough to send a crew of 12-18 people to the Moon to build a base.

NASA hopes to use a robot similar to DepthX to explore Europa, an icy moon of Saturn. Astronomers have long suspected that the icy moon of Europa has liquid water - and potentially an extraterrestrial life. A robot like DepthX can be launched into space aboard a probing ship, landing on the icy surface of Europa in a bullet-shaped base station capable of generating heat, which will then be dropped into the lane. icy, mysterious water below. One or more such robots will be smart enough to determine the direction to maximize the chance of detecting life.

DepthX tests the flexibility of a fully autonomous underwater vehicle that can move in tight spaces like caves. Once completed, DepthX does not need remote control or pre-programming, it will assess the surroundings in real time using the 54 ultrasonic sensors (A) provided by the ultrasonic transmitters ( B) control, together with an inertial guide, accelerometer and depth gauge. A Doppler (C) speed recorder monitors the movement speed of vehicles. This information is transferred to computers (D and E), from which the robot will draw a 3-D map of its surroundings and determine the next direction. To avoid blind spots, sensors are placed throughout the surface of this circular omnidirectional robot.

When the direction is determined, DepthX will move in by using 6 thrusters (F) to move, hover and find the correct way. The system follows the principle of redundancy - there are two vertical thrusters and four horizontal thrusters. If one engine does not work, the other will replace it. A floating computer (G) controls the valve, pump and compressed air system to push water out of the system. The aim is to achieve balanced buoyancy and to avoid wasting propulsion energy. Two battery towers (H) (also on the principle of redundancy, in case of a failure of the tower), are made of lithium-ion battery blocks with energy that can run 30 electric cars.