Proposal
Back to TopOverview and Goals
What are the goals of your rover?
Through meticulous design, the rover will be able to persevere through the uninhabitable weather and harsh conditions of the unforgiving lunar surface to overcome any task we throw at it. Seeing as this is the case, we've set expectations high and goals even higher. One these goals is the sending of the very first e-mail from the moon's very surface. Another of which is the task of being able to take pictures. Not normal pictures, however. The pictures taken would be of the moon's many ocular spectacles, such as ice, landscape, and artifacts from previous missions. To capture these various sights for viewers on Earth, the rover itself must be able to travel great distances, possibly up to 5000km.
How exactly would your rover accomplish said goals?
The rover will accomplish tasks with ease, due to advanced technological components. In this sense, it will utilize an on-board computer to store and compute data. This on-board computer will be on the durable 7075 aluminum frame. The frame itself is moved by thick Caterpillar tracks made of steel alloy turned by an electric motor. This motor, as well as all other electronic components on the rover, powered by a lithium-ion battery. Amongst the many other components are the camera, sensors, computer, navigation system, and multiple essentials. With all these bits and pieces working together, an unstoppable task-accomplishing machine that we can proudly call our rover is formed.
Back to TopInternal Components
The rover will have a 32-bit RAD 6000 microprocessor. The processor is powerful enough to process the data and is also resistant to radiation. The rover will have a 823 GB solid-state drive from BiTMICRO to store data. Compared to a conventional hard drive drive, a solid state drive is much more robust and efficient.
What are some issues about placing such electronic parts on the moon?
During the lunar day directly under the sun, much of the heat may be taken in. The harsh temperatures and radiation in space can easily interfere with the delicate electronic parts of the rover. Temperatures on the Moon's surface rises as high as 127 degrees Celsius and as low as -173 degrees Celsius [1]. This huge temperature difference requires a heat rejection and generation system in order to maintain the internal components at a constant and safe temperature. Just like humans, the rover needs to maintain a sort of homeostasis.
How will you resolve these issues pertaining to the temperature of electronic parts?
All of the electronics will be placed in a gold-painted box surrounding with aerogel, an amazing insulator. The gold paint also prevents heat to escape while the aerogel traps the heat inside, due to its high density [2]. To resolve all issues specifically pertaining to overheat, a propulsion system would be deployed to reject excess heat. This pump is capable of shuttling 150 watts of waste heat from the rover. Its working fluid is CFC-12m similar to freon used in older automobile AC. During the ice-cold lunar nights when temperatures are below 0 degrees Celsius, 4 Radioisotope Heating Units will be used to maintain the working temperatures of the electronic parts. These constant 1-watt heaters work through the decay of a low-grade isotope. Heat ejected from the computer can also provide warmth for the rover. To regulate it all, thermal switches and thermostats also will be used to turn on and off the heater according to the temperature.
Back to TopLanding
What is the surface of the moon like?
According to the book From Blue Moons to Black Holes the moon makes a complete revolution around the Earth in twenty-nine and a half days [3]. The World Book Encyclopedia states that the areas of the moon that are darker are known as Maria, because they looked similar to oceans. The Maria are composed of smooth rocks which came from cooled volcanic lava. The temperatures on the equator of the moon range from extreme highs of 127 degrees Celcius and extreme lows of -173 degrees Celcius. The temperature at the the north pole of the moon has a low extreme of 240 degrees Celcius [1].
Where on the moon will your rover land?
The most ideal landing location for the rover is Mare Imbrium, known as the Sea of Rains. The surface of this landing spot is covered with smooth rocks. It is also geographically close to the the north pole of the moon, where ice is. Since one of the rover's objectives is to photograph lunar ice, this location will be an ideal place to land. In addition, the rover will not need to endure the extreme high temperature of the equator, instead it will be able to survive the intense cold via the heating system. The time of landing will be when the near side of the moon faces the sun. This will allow the lunar rover to save its energy supply for the heating system until it reaches the northern part of the Moon.
How will it land at the location you've chosen?
The rover will be launched from the Earth in a capsule, and land via "direct ascent" so that the rover can come out upright. Also, a cushioning material within the capsule will allow the rover to reach the moon intact.
Back to TopMotor System
First and foremost, the rover has to have something that will move it. We hope to accommodate this facet by having treads, or continuous caterpillar tracks, that consist of many rigid units that are joined together by chain links. Treads will assist in distributing the weight of the rover over a larger surface area than wheels [7]. The rover will also incorporate a transmission with a 2:1 gear ratio that will increase the torque and decrease the speed of the robot. A transmission is a box of gears that can either increase speed while decreasing torque, increase torque while decreasing speed, or simply just changing the direction of the force applied [4]. An electric motor will provide the kinetic energy that is needed to move the treads. An electric motor will turn electric energy from a battery into mechanical energy that will rotate a drive shaft. DC Brushless electric motors have a shaft with an electromagnet in the middle, along with two magnets on the side. When electricity is applied to the electromagnet, the stationary magnets deflect the poles on the electromagnet and create motion [6]. The motor we will be using is the BEI Kimco DIP30-10-WEB1 DC Brushless Motor. This motor runs at 151.25 meters per second without any load, creates 36gram-meters of torque, and uses 17.5 watts of power to run at peak torque, and is roughly 311.84 grams. We will incorporate six of these in the overall rover design; four for the main treads, and two for the outrigger treads [8].
How dangerous would it be to place a rover on the moon? What are the dangers?
The moon is an incredibly hazardous place to put a defenseless rover on. The terrain itself will create the biggest challenge for the rover's motor system. The moon is littered with cracks and crevices that could prove lethal should the rover get stuck in one. The moon also has many craters from the constant collisions with objects in space that would create steep slopes and small hills and mounds. There will also be numerous small and large rocks on the moon that a rover could possibly hit and break one of its instruments on.
How will you overcome these mobility issues? What will you use and why?
However, our rover will be able to overcome all of these problems. Incorporating caterpillar tracks will allow our rover to cross over small cracks and craters in the ground without having a wheel getting caught. Tracks will be able to traverse over steep slopes as well as small obstacles. The rover's on board sensors will allow it to avoid larger obstacles. In addition, treads have better mobility than wheels with tires because they absorb shock better, smooth out rough terrain, and glide over small obstacles [7]. The modular chain links will be made from manganese steel alloy because of its high tensile strength and resistance to abrasion [5]. The drive sprockets and the axle will be composed of carbon nanotubes because of its rigidity. In our rover, we hope to utilize dual treads. By dual treads, we are referring to a tread system where there are two main treads of either side of the robot, and two smaller treads on the outside that will act as outriggers to balance the robot, as well as hands that will allow the robot to crawl over objects. An electric motor would be more suitable for the situation on the moon because an engine that uses combustion would not work since there is no oxygen in space [6]. The transmission that will be used for our rover will increase mechanical advantage, allowing the rover to climb steep hills and control its movement more precisely. Gears made of steel alloy will prevent the teeth from wearing down.
See an example of the motor system in action here.
Back to TopNavigation
One important aspect of the robot is, of course, its navigation systems, or how it is going to get around on the moon. The rover will employ a system based on cameras, lasers, and sensors to avoid obstacles and plot out the safest and most efficient path to its destination. The instruments it will be using to help with navigation are the gyroscope and the accelerometer; they will be used to determine the tilt of the rover.
What are problems the problems an automated rover can face when trying to navigate from one point to another?
Knowing where you need to go is very important. Whether you are trying to find your way to Las Vegas, or whether you are traversing the moon, navigation is a very important factor in any expedition. On the moon, you donˇ¦t have roads, signs or friendly locals to help you find your way. You also can't afford to tip over or fall down because the lack of gravity makes it nearly impossible to right yourself once you are on down. In addition to that, the terrain on the moon is quite unfriendly so you can't program the robot to take a preprogrammed route because you will almost certainly run into a problem. Problems such as falling into deep craters, bumping into large rocks, or wasting precious energy by taking unnecessary turns are always present on the moon.
How will you go about solving these problems? Why or how would your solution work?
Despite these drawbacks, the rover should have no trouble overcoming them. With the additional cameras strategically placed on the sides and front of the rover, the rover will be able to map out the landscape in a radius of roughly 3 meters around it. Using this information, along with software that calculates its inertia, it will then be able to travel to the predestined path without colliding with objects that would be unseen without the cameras [9][4]. To evaluate the situation, the rover will make frequent pauses that are approximately ten seconds apart from each other. When stopping, the rover will map out the area into an x, y, z coordinate graph. It will take the vertexes of the points to generate a map. It will use this map to navigate the terrain fluently and to send maps back to earth. The software used to calculate the roverˇ¦s inertia, along with other instruments, will also be used to keep the rover upright and balanced. With this knowledge, the rover will be able to reposition itself to avoid flipping over [11][12].
The navigation systems on the moon rover will ensure that it will be able to do its job, without having to worry about losing its way. The rover will use dual treads, have a transmission and motor, and use advanced instruments and cameras in order to plot its course and avoid obstacles. With its navigation set and done, our rover will be one step closer to completing its objective.
Back to TopPower
In order to survive the harsh conditions of space, necessary precautions must be made. A major factor for a successful mission is the rover's source of power. Without power, none of the components would be able to function properly and most importantly, there would be a loss of connection between the control room on Earth and the rover located on the Moon. With all of the internal and external components combined, the calculated energy usage of the rover is around 600 watts. The motor system uses 105 watts of power. The internal computer system uses 100 watts. The four heaters sum up to be 4 watts. Cameras equal 350 watts of usage and the rover's communication system use 40 watts of power.
How is your rover powered? Why have you chosen this source of power?
To power all the electrical components, lithium-ion batteries have been installed into the rover. This type of battery was chosen because it usually lasts from twenty-four to thirty-six months and only has a 5% loss of power each month. Under extreme temperatures, the batteries will lose charge quickly; however, with our solution, the batteries will be under a controlled temperature, eliminating the problem. These batteries have around 1200 recharge cycles. Although the rover is not planned to stay on the moon for such a lengthy amount of time, lithium-ion batteries are a safe and reliable decision because they can last much longer than the rover is planned to be in use. For every kilogram of battery, it is able to supply 1800-watts. The rover will have 20kg of lithium-ion batteries, which is will be enough to power the rover half a lunar day and still has extra power for backup.
The rover's battery will be recharged using solar panels. The rover's second source of power would be solar panels alongside with the lithium-ion batteries. The solar panels are installed and positioned on the rover in a strategic manner for it to receive the most energy. The moon rover will use the Sun as its source of power by converting the sunlight directly into electricity, a technology called Photovoltaics (PV)[13]. In Photovoltaics, solar cells or solar photovoltaic arrays are used. They are connected to the batteries that will serve as a storage area for the excess energy after the panels have been completely charged. Two 50-watt solar panels directly installed onto the rovers will be used to power the rover. The total surface area of the two solar panels will be approximately 100 meters squared [14]. The surface area of the solar panels are almost the same size as the rover itself so it can gather as much sunlight as possible. The crystalline silicon solar cells on these panels are positioned in an aluminum frame and connected with conductive ribbons to form many strings of solar cells. These strings are then all strewn together to form one large solar panel. They are covered with a sheet of glass to protect the cells from the harmful affects in the surrounding environment. Usually, the glass is tempered and low-iron. Approximately less than 5% of the sunlight is reflected off the glass but the glass is an essential component for a properly working and efficient source of electricity [15].
Back to TopCommunication
Communication will be a vital component for the rover. An antenna was chosen because of its versatility. It has great potential for receiving and transmitting data from our base back to the rover. However, an antenna alone will not be powerful enough to transmit the signal. In order to facilitate this facet, we will incorporate a DSN Satellite to boost the signal. There will be an on board wireless modem that will modulate and demodulate the radio waves that the antenna sends. In order to get the radio waves back to earth, the rover will have two different types of antennas. The first type of antenna will be a high gain antenna. This antenna is a directional antenna that has a built in motor that will move it around to point at the satellite.The second type will be a low gain antenna. This antenna will be omni-directional and can deliver information at a very slow rate. It will be used as a back up should the high gain antenna fail. The high gain antenna will be a circular disk with a diameter similar to that of a compact disk that uses 30 watts of power and will have a mass of around 70 grams. The low gain antennae will consist of a vertical rod that will use 10 watts of power and have a mass of around 30 grams.
What are current problems with space communication?
Communication between the rover and the moon may not seem like such a difficult task, but there are many problems that could occur on the moon. First of all, the moon is fairly far away from the earth. In addition, the earth's atmosphere will dissipate some of the signals. Also, our signals could get lost within the many signals that are being send out throughout the world. This happens when the frequency of another signal is too great and cuts through the connection between our satellite and the rover.
How will your rover resolve these problems?
In order to solve the problem over distance, we will use a deep space satellite. Data from the rover will be modulated by the modem and then sent up to the satellite, and then back to earth receivers. This will also eliminate the issues pertaining to the earth's atmosphere. The antenna that the rover will use is small but powerful. It can send data at a rate of 12,000 to 32,000 bits per second. Data, such as pictures of ice on the moon, will be sent back to earth. The solution for the signal dissipation issue is a special signal the rover will give out; which is a certain frequency of the electromagnetic spectrum. This frequency will go at speeds of which it will simply avoid dissipation by other frequencies [16][17].
Back to TopCamera
One of the rover's main objectives is to take high quality photographs of the Moon and map out the lunar surface. The rover will be using high definition panoramic cameras along with navigational cameras. The panoramic camera will be placed on top of a sturdy base strategically positioned on the rover in order to have a full view of the surrounding environment. Also, located on the top side of the rover are three cameras that will aide the rover with its navigation [18]. Altogether, these cameras will use up approximately 350 watts.
What must your rover's camera be able to do?
Taking high quality pictures on the Moon could prove difficult because of the lack of light on the moon. It will also be necessary for the rover to have varied shots of different places in order to gain a detailed view of the moon for future navigational purposes. The rover must also take a picture of itself due to contest rules and regulations. All three of these tasks and problems will be quite difficult to overcome, but they are not impossible.
How will your rover overcome these problems?
To unravel the concern of quality, a high definition panoramic camera will be put to use. It will produce one to two meter resolution images [19]. Since light is needed for one to see an object, the rover will always be on the bright side of things. In this case, it will be the bright side of the Moon. The base of the camera will be similar to that of a human arm, almost like a gimbal structure [20]. In this sense, it will be able to retract and turn up to 90 degrees. The camera itself is able to rotate 360 degrees. This will give the camera a wide-range of views on a certain object or a certain area. This also allows them to be able to adjust themselves to an angle that will allow a lovely self-portrait.
What other tasks can your cameras accomplish?
The navigational cameras are able to use the available visible light to generate three-dimensional, black and white panoramic images into a three dimensional map of the lunar terrain. These cameras serve as a safety precaution to prevent accidental crashes and unneeded traveling. Each navigational camera has a vision span of 45 degrees and since they are located on the front of the rover, there is full coverage of the path ahead. The rover is able to safely perform its assigned tasks on the Moon such as travel 5000 meters to a plotted point with the help of all these cameras.
Back to TopModels
Labeled Illustration
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Top Skeletal View
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Side Skeletal View
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Front Skeletal View
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Isometric Skeletal View
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eDrawing File
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MilkShape Source File (same as eDrawing file)
Requires the free MilkShape Program to view
Back to TopAnimation
Motor System Demonstration #1 (requires Adobe Flash Player)
Camera / Motor System Demonstration #2 (requires Adobe Flash Player)
Back to TopBibliography
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