PAYLOAD CONCEPT PROPOSAL. FREE FALL West Point High School

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1 PAYLOAD CONCEPT PROPOSAL FREE FALL West Point High School

2 1.0 INTRODUCTION Europa s plumes where first discovered by the Hubble Telescope in December The plumes have only been observed when Europa is at its farthest point away from Jupiter and when the plumes reach a height of about 22 km. With the plumes having been recently discovered there is not much more information known about these glaciers like plumes. Our team has taken on the challenge of uncovering some of these mysteries and will be voyaging to the South Pole where they are located. FREE FALL (Free Roaming of Europa s External Frontier And Lunar Landscape) was the name chosen for our team since our payload will be falling through the plumes. Our logo We are not falling. We are flying with style, which was derived from a quote in the Disney movie Toy Story. Our whole project will follow this theme. Our final design STARCOMMAND will be accompanying a U.A.H. designed orbiter on NASA s Europa Jupiter System Mission on a 1.9 year cruise to Jupiter where there will be a 700-day wrap around Jupiter then a 30-day orbit of Europa. 2.0 SCIENCE OBJECTIVE AND INSTRUMENTATION FREE FALL had many options of science objectives since STARCOMMAND will be the first payload to date to be sent to collect data there. Our payload will store three instruments to collect data directly, but it will indirectly give us much more information about the plumes. Our science objective is to determine the temperature, force, and pressure of the plumes. For temperature we will house a thermocouple that will continuously measure from deployment until impact. Pressure will be tested by using a pressure inducer. Four accelerometers placed evenly throughout our probes will determine the force and may also help us to determine what materials are being blown out of the plumes. Perhaps something beyond ice and water are being expelled from the plumes. It is known that Europa s plumes have only been spotted when Europa is farthest away from Jupiter. The theory for this is that there are cracks in Europa s ice-covered surface that release materials and that Jupiter s gravity causes these cracks to close when Europa is close and expand when it is farther away. To test if these plumes are completely closed or just too small, our four probes will be dropped at different intervals of Europa s rotation. The data STARCOMMAND collects will be a breakthrough since no probe has been sent through the plumes to date. Science Objective Pressure Temperature Force of Plume Table 1. Science Traceability Matrix Measurement Measurement Objective Requirement Determine the pressure Continuous above the surface and Measurement inside the plume. Record the temperature from the orbiter to impact. Determine the force of the materials being expelled from the plume. Continuous Measurement Continuous Measurement Instrument Selected Pressure Transducer Thermocouple Accelerometer Page 1

3 Table 2. Instrument Requirements Instrument Mass (kg) Power (W) Data Rate (Mbps) Lifetime Frequency Duration Colibry s RS9019.B Accelerometer Inertial Measurement Unit Continuous Continuous 0.06 <1 <5.12 Continuous Continuous Table 3. Support Equipment Table Component Mass (kg) Power (W) Other Technical Specifications Transmitter kg 1.7 W Up to 1200 bps uplink 96 x mm Antenna kg.02 W Power Consumption: 20 mw Space Batteries kg NA Size: Varies On-Board Computer kg.4 W 400 mw 96 x 90 x 12.4 mm 3.0 PAYLOAD DESIGN REQUIREMENTS Each team in this project was given certain requirements that we had to follow. Our payload should not exceed 10 kg in mass, measure over 44 x 24 x 28 cm while stowed in the U.A.H. orbiter, it should survive Europa s environment, and cause no harm to the main spacecraft. We will deploy from the spacecraft by using the helium provided to us by U.A.H. The functional requirements that STARCOMMAND must comply to are that: it must take data using our instruments, collect data, transmit it back to the orbiter using a transmitter, and provide power to our probes using batteries. 4.0 ALTERNATIVE CONCEPTS To come up with alternative solutions, FREE FALL divided into two groups. Our chief engineer and design team made up group one, and the project manager with the CEA team made up group two. Each team designed a concept that would meet all of the requirements and restraints. We then began our decision analysis to compare both concepts and design a final concept that would best fit the needs for our mission to be successful. The theme of Toy Story was used in the naming of the concepts deriving from Infinity and Beyond from Buzz s famous quote To infinity and beyond. Page 2

4 Alternative Concept 1: Infinity was created by the chief engineer and design team. It will consist of four Frisbee-shaped probes that will hold the functional instruments including an antenna, transmitter, and batteries. To achieve our science objective, there will be four accelerometers placed evenly throughout each probe and also a thermocouple and pressure inducer. To house the probes, we came up with a nerfgun shaped deplorer. Helium will pump through the housing unit and shoot the probe out. The probes will be deployed at a 90 degree angle opposite the orbiter. A spin to the probes will stabilize them as they descend through the plumes. See Figure 1 below. Figure 1. Group 1 Concept- Infinity Alternative Concept 2: Beyond was created by the project manager and the CEA team. Like Infinity, Beyond will be four Frisbee shaped probes. It will house a transmitter, antenna, batteries, accelerometers, a thermocouple, and pressure inducer. The difference in Beyond is how it will be deployed. The four probes will be deployed using helium but will be shot straight down into the plumes. See Figure 2 below. Figure 2. Group 2 Concept- Beyond 4.0 DECISION ANALYSIS Figures of Merits (FOMS) were an important part of FREE FALL, determining which concept would best achieve the science objective. We, as a team, picked many factors that were important for our concepts to completely be successful. The weight of each factor represents how important each figure of merit was, Page 3

5 with 1 being least, 3 having a higher significance, and 9 being the most important. Some of these include the importance of proper deployment and the accuracy of the probes hitting their target a plume and falling through. Each concept was then ranked on how well it would achieve the science objective. Infinity clearly out performed Beyond with a 333 over 130. See Table 4 below. Table 4. Payload Decision Analysis Figure of Merit Weight Group 1 Infinity Group 2 Beyond Durability Deployment Accuracy Mass Design Complexity Likelihood of Success ConOps Complexity Protection of Instruments Science Objective Science/Mass Ratio Total ENGINEERING ANALYSIS In our engineering analysis, we had six steps to figure out the total lifetime of our payload. First we determined the mass of our launcher to be 5.3 kilograms. We then determined that the mass of our four projectiles was 3.7 kilograms. With these figures we were able to calculate the pressure needed to leave the barrel, 2 P.S.I. We then determined the orbital velocity of projectiles to be kilometers per hour. Traveling at this speed, our projectiles will travel kilometers in the X-direction (left to right). Our transmitter is able to transmit data at a speed of bps. With this information we were able to determine the total lifetime of our payload to be six minutes and thirty seconds. See flow chart below. Figure 3 Flow Chart Page 4

6 6.0 FINAL DESIGN Infinity was the obvious design that worked for our science object. It had all the strengths we needed to perform the task we had chosen. We took this concept and made it our final design for the Europa Jupiter System mission. We renamed the payload STARCOMMAND, but it will function just the same as Infinity. After deploying by means of helium from the orbiter, our probes will fall into the plumes at a 90 degree angle in the opposite direction of the orbiter at an estimated speed of 536 km per hr. The Frisbee shape and spin of the probes will help them stay in their calculated path to the plumes without tumbling over. The four probes will be deployed at four different locations in Europa s rotation; one when Europa is farthest from Jupiter, the next when it is closest to Jupiter, and the other two when it is at its median of distance between the first two points. Once deployed, a thermocouple will measure the temperature until impact of the probes. This could be useful information on whether life could possibly be sustained here. A pressure inducer will test the pressure that is being placed on the probe. Four accelerometers inside the probe will determine the probes location and as it falls through the plume will show if the probe is affected by any debris hitting it. This data will be recorded and sent back to the orbiter continuously using an antenna and transmitter. Batteries will be provided on each probe to power these instruments. Each probe will have a lifetime of 6 minutes and 30 seconds. Figure 4. Payload Final Design STARCOMMANDER follows all requirements requested by U.A.H. Its mass stayed below the 10 kg limit with a total of 9.09 kg and volume not exceeding 44 x 24 x 28. It will not harm the orbiter when it deploys and will survive the environment will completing its science objective and transmitting the data back to the orbiter. Page 5

7 Table 4. Final Design Mass Table Function Mass (kg) Deploy 5.30 Measure 0.10 Collect Data 0.09 Provide Power 0.20 Send Data 0.10 House/Contain Payload 3.40 Total: 9.20 Table 5. Payload Design Compliance Requirement Payload Design No more than 10 kg of mass 9.20 kg Fit within 44cm x 24 cm x 28 cm when stowed 41 x 18 x 28 cm Survive environment Yes No harm to the spacecraft Yes 8.0 COMMUNITY ENGAGEMENT ACTIVITY SUMMARY The Community Engagement Activity or CEA is a great opportunity for the teams on the Europa Jupiter System Mission to show the community about our project, our science objective, and how we plan on reaching our goals. This is a chance for the creative members of our team to come up with a fun and hands-on project to get the community intrigued with what our teams are doing. Each person that was present to the CEA s was asked to complete a survey that would be collected and analyzed by the teams. Each team was given a goal of reaching five hundred surveys. CEA #1: Mentos Expansion Our first CEA was held on October 24, 2014 at West Point Middle School auditorium where we presented to fifth, sixth, seventh, and eighth graders. All five teams had tables set up that small groups of each grade would go to. FREE FALL s table was set up so that students could come by our table and hear a presentation on Europa s plumes and our science objective. They also got to see a prototype of our actual payload. We then provided an experiment of the plumes on Europa by a Mentos explosion. We wanted to teach how Jupiter s gravity affects the plumes. We simulated this by dropping Mentos into a diet coke that shot the soda ten feet into the air. To show what scientists believe the plumes are like on the other side of its rotation, we used regular coke that barely went one foot over the bottle. The students really seemed to enjoy this experiment. We received 545 surveys from this CEA. Page 6

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9 CEA #2: Parent s Night For our next CEA we will be hosting a Parents Night on December 4, Parents Night will be held at West Point High School Auditorium. We will describe the InSPIRESS process and explain each of our payloads to our friends, families, and community. We will be using our posters to display our past CEA and our final concept. We will give a twenty-minute presentation then open the floor for ten minutes of questions. We will be using this night to not only explain the InSPIRESS process but to also help prepare us for our final presentation. Page 8