Active Reserach Projects:
(Updated January 2021)
We are investigating non-pharmaceutical countermeasures to mental performance decrements experienced in spaceflight. We are currently evaluating stochastic resonance, which is a phenomenon in nonlinear systems where noise can increase the throughput of a signal. Previous studies have suggested that stochastic resonance improves perception within one sensory modality (e.g. auditory white noise improves auditory perception) or across separate sensory modalities (e.g. auditory white noise improves visual perception). This creates the potential to improve neural function and reduce mental workload in a non-invasive way. We aim to investigate the utility of this phenomenon and its applications to perception and higher-order mental processing.
Collaborators: Torin Clark
Undergraduates: Sasha Kryuchkov, Anna Jonsen, Maya Greenstein, Daniel Gutierrez, Abby Durell, Cody Watson, Michael Schlittenhart
Ph.D. - Jamie Voros*
Undergraduates - Maria Callas, Ponder Stine, James Rizkallah
Funding: This work is supported by the Translational Research Institute for Space Health through NASA NNX16AO69A under award number T0402.
Participant participating in a BrainStim experiment where white noise is added to stimulous into order to increase a visual theshold.
Acute Effects of Pressure and Posture on the Eye
Dr. Anderson led a study during her postdoc at the Geisel School of Medicine at Dartmouth College to investigate how posture as well as lower body positive and negative pressure affect the eye. These acute effects are relevant to the development of SANS because the same mechanisms that may lead to ocular findings in space, fluid shifts, hydrostatic gradients, and tissue weight, can be decoupled and studied on the ground through posture and pressure. We are finalizing analyses of the optical biometer and optical coherence tomography measurements made during this study to elucidate the effect of these three mechanisms on the eye. We hope to contribute to a knowledge of the effects of microgravity on the eye to inform SANS etiology theories as well as SANS countermeasures.
Collaborators: Dr. Jay Buckey, Geisel School of Medicine, Dartmouth College, Abigail Fellows, Geisel School of Medicine, Dartmouth College, Olivia Lantz, Geisel School of Medicine, Dartmouth College,
Ph.D.: Mike Van Akin
Funding: Grant CA03401 from the National Space Biomedical Research Institute through NCC 9–58, NASA EPSCoR Cooperative Agreement NNX13AD35A, National Science Foundation Graduate Research Fellowship
Development of a Lower Body Positive and Negative Pressure Device
A lower body positive and negative pressure device (LBPP/LBNP) seals the lower half of the body in quasi-airtight space, allowing a differential pressure between the upper and lower bodies to be introduced. This allows researchers to investigate the effects of fluid shifts on the body and to investigate the use of LBNP as a countermeasure to the physiological deconditioning that occurs in microgravity. We are adapting the CU Human Research Lab’s glovebox to be configurable to an LBPP/LBNP state. This includes the development of the lower body interface with the chamber, pressure vessel wall modifications, and the first positive pressure testing for the chamber.
Ph.D.: Mike Van Akin
Undergraduate: Anissa Becerra
Funding: National Science Foundation Graduate Research Fellowship, Undergraduate Research Opportunities Program
Wearable Inertial Sensors for Human Motion Capture Inside Spacesuits
A high incidence of injury is currently observed among crewmembers during extravehicular activity (EVA) and while training for EVA. Although it is known that this is a result of adverse mechanical interactions between the human and the spacesuit, designing spacesuits that more safely accommodate the wearer proves challenging due to the inability to observe the motion of the wearer relative to the suit. The current project investigates the use of inertial measurement units (IMUs) to observe human motion inside the suit and seeks to develop a wearable sensor system complete with self-contained power and data-handling. Contrary to past work in this area, this project seeks to achieve accurate joint kinematics estimation without the use of magnetometers, which have been shown to be unreliable due to the presence of time-varying magnetic disturbances inside spacesuits and in indoor environments in general. Instead, the project investigates techniques for improving attitude estimation with only inertial sensors using a variety of techniques including IMU arrays, bandpass filter linear acceleration modeling, and two-speed integration of attitude kinematics. The current project also investigates methods for quantifying and improving the performance of wearable sensor systems in the areas of comfort, mobility, and durability, each of which has hindered the application of such sensors inside the spacesuit in the past. The techniques developed in this work will provide spacesuit designers with unprecedented insight into human-spacesuit interactions, which could facilitate the design of spacesuits that safely enable longer and more frequent EVAs, as required by future human exploration mission architectures.
Ph.D.: Young-Young Shen
Undergraduates: Andres Villani-Davila, Justin Miller, Jiabin Lin, Shaylah Wood
Funding: NASA Quantifying and Preventing EVA Injury in Exploration Environments Grant NNX17AB11G (2017)
Interial sensors mounted on arm with space glove attachment.
Implementation of Dynamic Body Shape Models to Improve Spacesuit Boot Fit
Current spacesuit boots have fit issues leading to contact injuries and mismatched kinematics during gait. Many of these fit issues are dynamic: occurring while the foot is moving. As future missions target planetary destinations, such as the Moon or Mars, it will be important to have a spacesuit boot that is properly fitted, comfortable, and moves in coordination with the spacesuit operator. Spacesuit components are currently designed using linear anthropometric measurements and static body shape models. We hypothesize that by designing a boot around the changes in foot shape during gait, the boot will be better fit to the operator’s foot. Dynamic foot shape data was collected from a custom 4D foot scanner developed for this project. A dynamic parametric statistical foot shape model was constructed to predict foot shape from anthropometry and kinematic inputs. This dynamic foot shape model will be integrated into a new planetary spacesuit boot design, constructed, and tested for fit and mobility.
Collaborators: BOA Technologies
Ph.D: Abhishektha Boppana
Undergraduates: Steven Priddy
Funding: NSF GRFP
Dynamic foot scan captured during heel-off withour customed 4D scanner
Monitoring Behavioal Health in Operational Environments
Project Overview: Behavioral health problems are among the highest risks for astronauts on long-duration space exploration missions. These high-performing individuals are expected to maintain psychological health and cognitive performance while being exposed to an isolated, confined, and extreme (ICE) environment that delivers constant psychological stressors for extended durations. In this work, we are investigating different methods of monitoring these individuals within three main areas: 1) survey instruments, 2) wearable textile-integrated physiological sensors, and 3) automated stress-detection algorithms based on physiological signals. We have developed and tested different types of textile electrodes for heart monitoring, including the woven electrodes pictured below (developed in collaboration with Prof. Laura Devendorf). Recently, we found a silver lining of the pandemic and conducted a survey-based study to better understand the impact of prior experience and training on participants’ abilities to cope with isolation and confinement. Currently, we are working on methods of detecting acute stress using novel parts of the electrocardiogram (ECG) and electrodermal activity (EDA, i.e., sweat response) signals for operational use. With this research we aim to improve our understanding of the stressors of long-duration spaceflight and their impact on behavioral health while connecting our findings to areas of need within the Earth-bound population such as veterans of war, researchers at the Earth’s poles, prisoners, and others working in high-stress operational environments.
Collaborators: Dr. Andrea K Webb, Draper, Prof. Laura Devendorf, Unstable Design Lab, ATLAS
PhD: Katya Arquilla
Undergraduates: Sarah Leary (B.S., Aero)
Funding: Draper Fellowship
Right: Swatch of fabric with woven electrodes coming of the TC2 automated loom
Left: Close-up of a woven electrode with integrated silver-coated thread.
Real-time Unobtrusive Monitoring of Trust, Workload, and Situation Awareness through Psychophysiological and Embedded Measures
As humans venture farther from Earth, the spaces they inhabit will increasingly rely on autonomous systems to keep them alive, happy, healthy, and productive. Current mission architectures, such as that of the ISS, are able to rely heavily on frequent resupply missions and near-constant ground support; however, next-generation architectures will require efficient teaming between human crews and largely autonomous habitats. An intimate understanding of factors like crew trust in autonomy, workload, and situation awareness (TWSA) will lay the groundwork for robust deep-space human-habitat teaming. Current gold-standard measures of TWSA are often very subjective in nature and require the administering of obtrusive questionnaires. Additionally, humans’ psychophysiological responses have long been studied as a proxy for TWSA, yet much of this work has been constrained to the laboratory environment and has tended to monitor only one facet of TWSA at a time. Our research aims to develop a novel methodology for monitoring and discriminating TWSA cognitive states, given a lean and unobtrusive psychophysiological data stream. We have begun this process by developing an immersive and contextualized piloting task inside our HL-20 DreamChaser mockup, where we can manipulate and measure TWSA. Psychophysiological measures collected include electrocardiogram (ECG), respiration rate, electrodermal analysis (EDA), and eye tracking. Moreover, we have developed embedded measures that leverage specific aspects of task performance to infer TWSA cognitive states. These techniques have larger implications for the field of human-computer interaction as a whole and will be increasingly relevant for aerospace and more as autonomous systems become more ubiquitous.
Masters: Johnny Zhang
Undergraduates: Evie Clare
Funding: NASA Habitats Optimized for Missions of Exploration Space Technology Research Institute
Subject partcipating in HOME experiment
Hybrid Spacesuit Design for Martian Surface Exploration
This research aims to explore and develop a novel spacesuit architecture in order to advance the effort of exploring the Martian surface. The suit concept would incorporate novel uses of developed materials for an advance material layup specifically designed for Martian surface exploration as well an exploration of a suit concept that comprise of both mechanical counter pressure (MCP) and gas pressure (GP) systems to achieve a more dynamic pressure system that utilizes advantageous aspects of each design, as well as offers redundancies for additional safety. As we set our sights towards Mars, extravehicular activity (EVA) will continue to be fundamental to human space exploration and will be one of the driving objectives of such a mission. Improvements and adaptations to current EVA spacesuits are imperative in order to enable our astronauts to successfully perform tasks on the Martian surface without risk of injury from the spacesuit or the environment. During the Apollo era, injuries from gas pressurized suits were common and well documented with many astronauts experiencing shoulder, hand, and neck injuries from the extra space, lack of fit, and stiffness of the GP spacesuits. Those missions were only a fraction of the duration of a future Mars mission. We continue to see these injuries and limitations today with our astronauts performing tasks on satellites and ISS. In addition, the metabolic work needed to move and perform tasks in the current spacesuit put astronauts at risk of over exertion and fatigue, because of the bulk and mobility restriction. This could lead to an increase in potentially catastrophic errors and place astronauts at risk. Because of the unique challenges of the Martian surface and the increased duration that explorers will be spending in the suits, current designs will be a limiting factor in the success of surface exploration and the main cause of injuries for the crew. Through a capstone demonstration of a hybrid EVA glove, we will show improvements in dexterity, pressure, and comfort in comparison to the current glove design.
Schematic of the hybrid spacesuit concept.
In-Suit Wearable Sensing System
Gas pressurized space suits cause injuries and significantly increase metabolic expenditure. It is challenging to quantify how the person moves relative to the suit, which is the genesis of EVA-related injuries. Many techniques of assessing suit performance cannot evaluate suited human biomechanics because they measure performance from the outside of the suit, characterizing the human and space suit as a whole. We are developing wearable sensing systems for use inside the space suit that integrate pressure sensing, joint angle measurement, and physiologic monitoring. Our emphasis is on modular sensor systems that can be used in different regions of the body over a wide range of anthropometries
Virtual Reality for Space Vehicle Mock-up Design
Space vehicle design is critical to maximize crew efficiency, comfort, and equipment storage. Designers utilize mock-ups early in the design phase to experiment with ideas, but high-fidelity mock ups can be costly and time consuming to produce. Therefore, many design decisions have been set in place by the time a high-fidelity mock-up is created. Engineering drawings allow early assessment of vehicle design, but do not allow experimental evaluation of physical presence of people interacting with the system. Further, when testing mock-ups in 1G, our perspective is limited by our orientation and by interacting with the vehicle in 1G. This limitation is removed in microgravity, where astronauts interact with the vehicle or habitat in ways not possible on Earth. To enable efficient and rapid mock-up of vehicle concepts, we are investigating the use virtual reality earlier in the design process to achieve improved system design.
Distortion Product Otoacoustic Emission Mapping
This project assessed distortion product otoacoustic emissions (DPOAE) as a non-invasive measure of intracranial pressure changes. DPOAEs are created in the inner ear when outer hair cells are stimulated by sound. Changes in intracranial pressure have been shown to cause changes in DPOAEs. The long-term interaction between intracranial pressure and the eye may cause visual acuity changes in spaceflight. Unfortunately, there is no noninvasive, easy-to-perform, on-orbit measure of ICP to test this hypothesis. The technique used here, DPOAE level/phase mapping, collects DPOAE data at multiple sites throughout the cochlea and so provides a comprehensive picture of cochlear responses to ICP changes.
Intraocular Pressure in Artificial Gravity
The purpose of this study is to investigate the effects of artificial gravity (AG) as applied via a human centrifuge on the pressure within the eye. This pressure is known as intraocular pressure (IOP). Astronauts are returning from long duration spaceflight with visual acuity and structural changes to the eye, but the cause has yet to be determined. AG offers a comprehensive countermeasure that may be preventative of these problems, even if the mechanism is not determined. We are investigating AG as a potential countermeasure in conjunction with Prof. Torin Clark’s research team.
*student of Dr. Torin Clark
** student of Dr. Dave Klaus
*** student of Dr. Jim Nabity