AACRE Research Showcase
Anna Mattinger
Before AACRE [Stanford Engineering’s Aeronautics and Astronautics Community Research Experience], print(‘hello world’) was most of my Python repertoire, I’d only just finished Calculus, and I’d never heard of UWBs, the Ultra WideBand tracking sensors that have since dominated my waking thoughts. If you hadn’t heard about them either, that’ll change: UWB is in vogue, showing up in the development of new smartphones, cars, medical tech, and other devices, largely as an improvement over GPS, Bluetooth, and Wifi.
I joined the Stanford NAVLab, and one of Professor Grace Gao’s projects at the cutting-edge of sensor fusion, the goal of which is autonomous tandem drifting [with cars—i.e., fast, furious, just what it sounds like!]. Aside from being intrinsically rad, this represents a milestone that has never been reached before—a system fast, accurate, and precise enough that cars skidding around a racetrack can reliably avoid collisions. A highly dynamic edge case like this isn’t just fun, but has wider applicability when it comes to creating autonomous navigation systems that we can trust to function in unexpected scenarios.
During my first week—primarily doing literature review on error characterization—it took ten google searches to even begin to understand one sentence of an abstract. By the end of the first month I had, among other things; written reports on papers I’d worked hard on understanding; made a GitHub repository of unit tests I’d written from scratch to clean and analyze data; done in-person test driving in a Frankensteined vehicle to collect location and motion data; attended technical webinars; built rapport with my advisor and mentors; and profoundly expanded my technical vocabulary. The program rewards, and demands, being self-motivated over having prerequisite knowledge. There is an abundance of both support and freedom, pliable ceilings, and tons of room for customization—I’ve leveled up more this one summer than over last year’s full-time STEM course load. AACRE offers so much more than a looks-good-on-paper opportunity.
Nazih (Ned) Bitar
When I joined the Aeronautics & Astronautics Community Research Experience (AACREs) program, I worked with Professor Mac Schwager in the Multi-robot Systems Lab (MSL). I had plenty of experience building and racing multi-rotor platforms, specifically quad-rotors – but I didn’t know just how many new skills I would learn with MSL to help drones avoid crashing.
As drones fly they need to dodge buildings, trees, and even people to avoid smashing themselves to pieces. Working with Professor Schwager we explored how to help drones ‘see’ and ‘think’ to avoid collisions. I paired up with a graduate student of the MSL Lab, Adam Caccavale, and we worked to develop software that helps drones navigate safely using Visual-Inertial Odometry (VIO). It sounds like a simple task, but the issue is that racing drones design follows a very bare-bones philosophy - they are designed to be ultra light-weight and fast. I had to find a way to extract data from the drone. My day-to-day tasks varied throughout the project, and my first day consisted of just trouble-shooting and diagnosing issues to get the quad-rotor off the ground; installing new rotors that would produce enough thrust to lift the drone and the camera, and designing and 3D printing a custom frame to hold the camera steady. Finding the VIO package was the easy part, but getting it to work was the biggest challenge - it required me to learn many things I was not familiar with before; installed and using Linux, a ROS (Robotic Operating System), and C++, and Python. After two weeks of dead-ends and failures, including a hard-drive failure, I finally succeeded, and was able to compile a ‘ROS Bag’ using a test set of data, to help the drone understand what it was ‘seeing’.
During my time in the AACREs program, I found that research is like a black box – until you explore the data, you don’t know what you are going to learn. By exploring how to help drones ‘see’ with a camera, and ‘think’ to avoid crashing, I also discovered how to code in Python, 3D print parts, and even rebuild a hard drive’s lost data – and that’s just all part of a day’s work to help drones crash less.
Nadin Souki
Before AACRE [Stanford Engineering’s Aeronautics and Astronautics Community Research Experience], print(‘hello world’) was most of my Python repertoire, I’d only just finished Calculus, and I’d never heard of UWBs, the Ultra WideBand tracking sensors that have since dominated my waking thoughts. If you hadn’t heard about them either, that’ll change: UWB is in vogue, showing up in the development of new smartphones, cars, medical tech, and other devices, largely as an improvement over GPS, Bluetooth, and Wifi.
I joined the Stanford NAVLab, and one of Professor Grace Gao’s projects at the cutting-edge of sensor fusion, the goal of which is autonomous tandem drifting [with cars—i.e., fast, furious, just what it sounds like!]. Aside from being intrinsically rad, this represents a milestone that has never been reached before—a system fast, accurate, and precise enough that cars skidding around a racetrack can reliably avoid collisions. A highly dynamic edge case like this isn’t just fun, but has wider applicability when it comes to creating autonomous navigation systems that we can trust to function in unexpected scenarios.
During my first week—primarily doing literature review on error characterization—it took ten google searches to even begin to understand one sentence of an abstract. By the end of the first month I had, among other things; written reports on papers I’d worked hard on understanding; made a GitHub repository of unit tests I’d written from scratch to clean and analyze data; done in-person test driving in a Frankensteined vehicle to collect location and motion data; attended technical webinars; built rapport with my advisor and mentors; and profoundly expanded my technical vocabulary. The program rewards, and demands, being self-motivated over having prerequisite knowledge. There is an abundance of both support and freedom, pliable ceilings, and tons of room for customization—I’ve leveled up more this one summer than over last year’s full-time STEM course load. AACRE offers so much more than a looks-good-on-paper opportunity.
Gabriel (Gabe) Larot
For me, the exciting part about electric propulsion is that it offers interesting advantages to future space travel compared to traditional chemical propulsion engines. Electric propulsion is more efficient than chemical engines, as using electrical energy to move spacecraft in space requires much less energy to produce the same amount of velocity. This is an important weight-saving idea when each kg costs around to get up above Earth!
Before I joined the AACRE program, during my seven years of duty with the United States Navy I understood the feats of engineering involved in moving giant ships and their armament equipment. My fascination with the design and energy use of crafts led me to focus my work on propulsion in space, and I joined Professor Ken Hara in the Plasma Dynamics Modeling Laboratory to explore electric propulsion used by Hall thrusters.
Hall thrusters utilize electric and magnetic fields to accelerate charged particles. Chemical propulsion engines are much less efficient, but smaller electric propulsion engines can produce continuous force for very long periods of time and are more sustainable. This makes them particularly good for missions requiring vast distances and lengthy missions. Electric propulsion engines are currently being developed, and it’s important to understand and model how these engines would work before we begin to build them.
My work with the Plasma Dynamics Modeling Laboratory this summer has been to research the effects of electric field oscillations on particle trajectories. By programming software to simulate a set of individual particle trajectories, I was able to study possible casualties of electron transport across the magnetic fields. Although electrons and Xenon plasma are generally trapped within the confines of the radial area of the Hall thruster by the applied magnetic field, the exact causality of anomalous electron transport continues to elude scientists, so it was a tough but very satisfying research topic! After weeks of creating programs, running simulations, and gathering data, I was finally able to analyze the electrons that were most perturbed by the plasma waves. This helps us understand how electric propulsion engines will work, and hopefully one day my results could be used to further the advancement of simulations that identify anomalous electron transport across magnetic fields.
During my time with the AACRE program I’ve learned a lot of new skills, but best of all, I got to be a part of the research that may lead us to more sustainable spacecraft, and ultimately, to be able to explore more of our universe.
Brandon Bullock
Beyond the three familiar states of matter we know as solids, liquids, and gasses exists a fourth state called plasma where charged particles push and pull against one another in a breathtaking display of energy and motion that fuels stars. Plasma also has the potential to revolutionize our planet with applications ranging from nuclear fusion to plasma propulsion for spacecraft. However, to unlock this potential we need to bridge theoretical behavior with the practical control of plasma. This is where computational modeling comes in, serving as the virtual laboratory where we can simulate extreme plasma conditions and find otherwise unattainable insights.
During the AACRE Program (Aeronautics & Astronautics Community Research Experience), I joined Stanford’s , led by Professor Ken Hara, and developed simulations modeling how charged particles behave when subjected to different electromagnetic forces. Because of the varied forces and particle types within plasma, modeling entire plasma systems is too computationally expensive - who wants to sit and wait for years for a program to finish running? But simulating just one part, a single charged particle, enables us to build predictive models of how they move in different situations, and these models can be used to simplify larger simulations allowing us to discover and optimize real world plasma applications.
At the start of summer, I knew nothing about plasma, by the end I had worked with my graduate mentors Vedanth Sharma and Adnan Mansour to conduct literature reviews, on electromagnetic theory and numerical plasma modeling methods; learn MATLAB and C++, where I wrote hundreds of lines of code to model charged particles in varying electric and magnetic fields; use excel to analyze the millions of data points each simulated particle created, eventually creating mini-programs built into my model to streamline regression analysis; and used Sherlock, Stanford’s supercomputer, to model thousands of plasma particles. Through the AACRE program, I've witnessed how those rare moments of discovery, despite the missteps and failures, have a remarkable ability to fill you with inspiration. And with the skills I’ve developed showing me what I’m capable of accomplishing, I feel empowered to pursue my own moments of discovery.
Ricardo Manzanares-Diaz
There are millions of planets orbiting far-away stars outside of our own solar system, and we need to find out what they look like and what they might be made of - but taking pictures of these planets is not as easy as pointing a space telescope at it and telling the planet to “say cheese!”. There are many challenges we have to overcome; especially the bright light from the stars that these exoplanets orbit. Imagine looking up at the sky and trying to take a picture of an airplane near the Sun. Seems like a simple enough task, but you’d notice that the Sun’s bright light gets in the way - the glare is too much to be able to take a picture of the airplane, unless you cover the Sun’s light. By putting your thumb up to block out the light from the Sun, you are able to see the plane more clearly and take your picture. To bring things back to scale, the airplane is an exoplanet, the Sun is the star that the exoplanet is orbiting millions of miles outside our solar system, and your thumb is a large structure in space meant to block out the star’s light - a ‘starshade’.
At the Morphing Space Structures Laboratory, Professor Manan Arya works on starshades, remarkable structures that use origami to start out in a folded configuration and unfurl in space, ‘blossoming’ into a light-blocking shade that can reach a diameter of 85 feet. These starshades can block any incoming light from stars that exoplanets orbit. The pedals and the gaps between them allow space telescopes to point between them and take a picture of the exoplanets, without the light getting in the way. To take this back to our hand-airplane analogy, we can spread out our fingers slightly, and the gaps between allow for the camera to take a good picture.
Making sure a starshade unfolds correctly is a challenge - when the starshade unfolds, the rods that help keep the center structure intact during transport break off and are extracted. This leaves holes that can compromise the starshade’s effectiveness. Working with Professor Manan Arya in the Morphing Space Structures Lab, I helped figure out how these bolt ‘passthrough’ holes will close themselves up, automatically, reliably, and without leaving any gaps for light to ruin the space telescope's picture. Using OnShape and Fusion360, I created CAD sketches of passthrough designs to see how they would work, before prototyping them using paper mockups. I also 3D printed fixtures that would hold the passthroughs out of PLA plastic, figuring out the printing parameters and revisions to ensure stability for the passthroughs. Then I iterated my designs and made them out of metal, cutting out the blades from thin blue tempered steel. Once I had a working prototype, I used mechanical testing to determine the minimal force needed for the blades to smoothly close and stay in good condition. Making sure the passthroughs worked every time was a priority, as there are no spare parts or repairs in space!
Balancing the internship, work, school, and life has been challenging over the last 10 weeks of AACRE, but the connections, experiences, and feelings of progress made it worthwhile. I cannot wait to see the next steps of evolution for origami in space and how it will help humanity. When I first decided to major in Aerospace Engineering, I did not know whether I wanted to focus on airplanes or space structures. As I apply to transfer to University to study for a Bachelors, I’m excited for the next opportunity to work with space structures. The AACRE program has not only allowed me to acquire experience and skills, but also the confidence necessary to operate in this daunting yet fascinating field.