WOMBAT
Ergonomic 3d printed toilet that through coaxial rings and the principle of electrostatics contains human waste.
OVERVIEW
Design of an innovative space toilet concept for low-mass, compact toilets that reduces the current state-of-the-art toilet mass by more than half and reduces the volume by more than a quarter, also allows astronauts to urinate and defecate in both lunar gravity and microgravity.
Context
Project for NASA's Lunar Loo Challenge in collaboration with HeroX for NASA's Asrtemis 2024 mission.
My Skills
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UX Research
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User Testing
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Interaction Design
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Electronics
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Participatory-Design
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Partner Management
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3D Modelling
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Rendering
Team
Deliverable
Time
-
Paola Ruiz
(UX Researcher & Product Designer)
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Carlos Rojas
(Electrical Engineer & Avionics Specialist)
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Rafael Rivera
(Mechatronics Engineer & Aerodynamics Specialist)
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Qualitative UX Research
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Synthesis & Documentation
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Initial Concept Sketches
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Test Experiments Outcomes
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Documentation
Summer &
Autumn 2020
WOMBAT
Ergonomic 3d printed toilet that through coaxial rings and the principle of electrostatics contains human waste.
OVERVIEW
Design of an innovative space toilet concept for low-mass, compact toilets that reduces the current state-of-the-art toilet mass by more than half and reduces the volume by more than a quarter, also allows astronauts to urinate and defecate in both lunar gravity and microgravity.
Context
Project for NASA's Lunar Loo Challenge in collaboration with HeroX for NASA's Asrtemis 2024 mission.
My Skills
-
UX Research
-
User Testing
-
Interaction Design
-
Electronics
-
Participatory-Design
-
Partner Management
-
3D Modelling
-
Rendering
Team
Deliverable
Time
-
Paola Ruiz
(UX Researcher & Product Designer)
-
Carlos Rojas
(Electrical Engineer & Avionics Specialist)
-
Rafael Rivera
(Mechatronics Engineer & Aerodynamics Specialist)
-
Qualitative UX Research
-
Synthesis & Documentation
-
Initial Concept Sketches
-
Test Experiments Outcomes
-
Documentation
Summer &
Autumn 2020
TITAN
Radio controlled aircraft, designed to simulate colonization on Mars, with a variety of payload being released mid-flight.
OVERVIEW
Design of an innovative radio-controlled aircraft. the goal of this undertaking was to gather engineering knowledge and skill, master new techniques and information and apply these to the successful design and fabrication of an aircraft which matches the requirements set by SAE for its Aero Design Competition.
Context
Project for SAE Aero Design East Competition, Lakeland 2020, with school association UNAM Aero Design
My Skills
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UX Research
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Mechanical Design
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Aerodynamics Design
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Avionics
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Project Management involving adjusted deadlines and scope
Team
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Itan Romo
(Avionics Specialist)
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Andrea López
(Industrial Designer)
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José Ángel Chávez
(Mechatronics Engineer & Aerodynamics Specialist)
Deliverable
Time
-
Qualitative Research
-
Documentation
-
Initial Concept Sketches
-
Test Experiments Outcomes
-
Documentation
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Tangible aircraft
August 2019 - March 2020
THE CHALLENGE
SAE Aero Design includes a competitions that challenges participating teams to conceive, design, fabricate, and test a radio controlled aircraft that can take off, land, and optimally meet the mission requirements. This exercise allows students to apply knowledge gained in the classroom in a real work environment. To help develop the students’ written and oral communication skills, a sizable percentage of each team’s score is devoted to the design report and oral presentation required in the competition.
RESEARCH
There are several different variables that involve designing and creating an aircraft, in order to build the aircraft we needed to perform several activities.
A research in materials and a brainstorm to manufacture efficiently ,while keeping the overall cost in mind, were performed. We applied cost optimization in a business-focused way, taking into account spending and cost reduction, while maximizing the business value of our aircraft.
The first parameter to consider, after SAE’s motor restriction, was the speed driven by the propeller at maximum efficiency (pitch), which must be at least twice the speed of the loss of the aircraft.
A detailed and iterative process was made, where it was sought to have an efficient structure and the lowest weight. For this, the idea of a Pratt structure was taken along the entire fuselage, both on the side walls and on the upper and lower rear, we implemented an autopilot system for the gliders, we also developed a program with a microcontroller that processes the data and this data is displayed in a graphical interface.
DISCRIMINATORS
Since we were not a representative team from the US and we need to transport the whole aircraft, we decided to use a wing that could be divided into two parts. Not having full time access to a landing track made it harder to perform the tests of the aircraft and do not having aeronautical specialized professors which could serve as mentors was another disadvantage.
PROTOTYPING
Since we were not a representative team from the US and we need to transport the whole aircraft, we decided to use a wing that could be divided into two parts. Not having full time access to a landing track made it harder to perform the tests of the aircraft and do not having aeronautical specialized professors which could serve as mentors was another disadvantage.
Sketches and components
I was in charge of the wing and the tail design, they were designed keeping in mind the mission requirements, the overall cost and the manufacturing complexity. A decision matrix was made to choose the best wing and tail configuration. The matrix considered relevant design features set in different priorities, like its weight, a non-complex manufacturing and other aerodynamic properties were some of the considered features in the analysis. In our trade off analysis, a high wing with an H empennage was selected for the plane configuration.
The most important structure factors to consider were the functionality, performance and a non complex manufacturing procedure and assemblies; Also is the reason to use truss along the fuselage. Among the Pratt, Warren and Howe truss options, an analysis was performed, resulting Pratt truss to be the most reliable choice due to its arrangement with diagonal elements in tension and the vertical fragments under compression.
Aircraft side view
In order to get a better visualization for possible solutions to the requirements of the aircraft, 2D diagram was displayed from a 3D formation as shown, easing the process to develop the envelope of the aircraft and the placement of Pratt truss elements.
2D Aircraft Truss
To run a structural analysis, many load cases were highlighted, considering the takeoff and landing of a fully loaded aircraft as the most crucial one. Taking into consideration the possible inaccuracy of the calculus caused by simplifications, the cases in which the loads of the airplane are surpassing the expected ones and the forces and support reactions interacting with the truss, we decided to enforce a security factor equal to 1.5. The method of nodes and sections was used, drawing line elements and obtaining their forces through a free body diagram of the airplane with the landing gear data previously obtained in order to maintain the equilibrium.The results were endorsed through a 2D and a 3D analysis on ANSYS
Aircraft materials were decided to be the prime resource to build the prototype, highlighting among them balsa wood and plywood. Laser cut, gauges, inventories and blue prints of some parts in 1:1 scale were used to regulate and restrict certain factors to warrant the aircraft’s quality in its manufacture. These tools also contributed as a guide for a faster process, while preventing errors during its execution.
The main innovation was 3D printing of custom parts, that not fulfill very specific needs of the aircraft, but that can't be found in the current market, such as the nose gear joints and the cargo system release.
3D printing parts of the cargo release system
To make an ideal component selection for the data acquisition system, the requirements were prioritized in two groups: mandatory and desired; the mandatory are the requirements in SAE Aero Design rules, and the desired are optional but useful. After a trade analysis, we choose the BMP280 barometer to read altitude data, MPU9250 to measure the angle of rotation in each axis, GPS Neo Ublox 7M and in order to establish communication between the airplane and the ground station, a couple of Xbee S3B 900 Pro were chosen, because its compliance with SAE requirements while its ease of programming. We decided to use a microcontroller to establish communication with the sensors and to process all the information without delays.
Telemetry system block diagram
Regarding the glider selection we chose a delta-wing configuration, allowing to control the glider using just ailerons, reducing weight removing the empennage and its respective servomotors. Styrofoam was selected for the glider material because of its low density. The airfoil selected was a selig SD7062 which is a freestanding airfoil which is required for the CDA in order to glide balanced without using stabilizer. Thus, the cabin lays upon the wing, saving the weight of a fuselage. (Azcárate 2015)
The aircraft microcontroller selection was based on the number of servos that needed to be controlled and the serial ports that it requires to send and receive information. Four PWM ports, two serial ports and a processor capable of obtaining data from sensors in order to send information without delay were required, finally an Arduino Mega was selected.
REFLECTIONS
My favorite part of the creating this project was seeing our plane fly. Just seeing all our hard work in the past six months pay off in building and designing the aircraft. This was for me a real-life engineering challenge. In this competition, we had to perform trade studies and make compromises to arrive at a design solution that will optimally meet the mission requirements while still conforming to the configuration limitations. We designed and built the aircraft from scratch.
I am extremely proud of the effort of our Aero Design team members. They never gave up and taught me the importance of team work and leadership.
