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Status and Future of the EDEN ISS Mobile Test Facility
Abstract
Within the EDEN ISS project an international consortium designed and built a (semi-)closed loop greenhouse, called the Mobile Test Facility, to investigate and validate techniques for plant cultivation in future bioregenerative life support systems. At the end of 2017 the Mobile Test Facility, consisting of two modified 20 foot shipping containers, was transported to the German Neumayer Station III in the Antarctic for testing in a space-analogue environment. Following arrival in the Antarctic in January 2018, and initial system checkout activities, the Mobile Test Facility began its first operational phase in February 2018. Although the EDEN ISS project foresaw only one year of operations and the project has officially concluded, the Mobile Test Facility remains in the Antarctic, operating at least until the end of 2020 and possibly beyond. This paper describes initial results and lessons learned from the 2018 and 2019 operations of the Mobile Test Facility, and presents an overview of the intended activities for 2020 and beyond.
... Within the EDEN ISS project, a greenhouse facility was built in Antarctica to test key technologies for use in future planetary surface greenhouses under extreme environmental and logistical conditions (Zabel et al., 2016;Schubert et al., 2018;Vrakking et al., 2020b). The greenhouse, called Mobile Test Facility (MTF), was installed near the Neumayer III Antarctic Research Station (NM III, 70 • 40´S, 8 • 16´W), which is operated by the Alfred-Wegener-Institute for Polar and Marine Research (AWI) (Gernandt et al., 2007;Wesche et al., 2016). ...
... Using predefined procedures for maintaining the systems in an operable condition, such as exchanging filters or refilling tanks, but also for sowing, tending and harvesting the plants, or for cleaning of the greenhouse, these teams operated the MTF with the main focus to produce fresh food for consumption by the wintering crew. This enabled the possibility to investigate how a space analogue greenhouse can be operated in collaboration between a remote team, the RST, and a relatively untrained OOT in Antarctica as well as to examine the related CT, WL and operation processes (Vrakking et al., 2020b). ...
... As depicted in Fig. 2 the cultivation of plants in the greenhouse started in winter season 2019 approximately three months after the SMT 2018/2019 left the NM III. This was done because DLR wanted to investigate the option of restarting the systems of the MTF from the MCC after a hibernation phase lasting more than 2.5 months (Vrakking et al., 2020a;Vrakking et al., 2020b), which ended on 06.05.2019 with first activities of the on-site operators inside the facility. The startup of all the systems in the MTF after the hibernation phase was on 16.05.2019 ...
The goal of the EDEN ISS project is to research technologies for future greenhouses as a substantial part of
planetary surface habitats. In this paper, we investigate crew time and workload needed to operate the space
analogue EDEN ISS greenhouse on-site and remotely from the Mission Control Center. Within the almost three
years of operation in Antarctica, different vegetable crops were cultivated, which yielded an edible biomass of
646 kg during the experiment phase 2018 and 2019.
Operating in such a remote environment, analogue to future planetary missions, both greenhouse systems and
remote support capabilities must be carefully developed and assessed to guarantee a reliable and efficient
workflow. The investigation of crew time and workload is crucial to optimize processes within the operation of
the greenhouse. For the Antarctic winter seasons, 2019 and 2020, as well as the summer season 2019/2020, the
workload of the EDEN ISS greenhouse operators was assessed using the NASA Task Load Index. In addition, crew
time was measured for the winter season 2019.
The participants consisted of on-site operators, who worked inside the EDEN ISS greenhouse in Antarctica and
the DLR remote support team, who worked in the Mission Control Center at the DLR Institute of Space Systems in
Bremen (Germany).
The crew time results show that crew time for the whole experiment phase 2019 required by the on-site
operator team 2019 is approximately four times higher than the crew time of the corresponding remote support team without considering planning activities for the next mission. The total crew time for the experiment
phase 2019 amounts to 694.5 CM-h or 6.31 CM-h/kg. With the measurements of the experiment phase 2019 it
was possible to develop a methodology for crew time categorization for the remote support activities, which
facilitates the analysis and increases the comparability of crew time values. In addition, the development of
weekly and monthly crew time demand over the experiment phase is presented.
The workload investigations indicate that the highest workload is perceived by the remote support team
2019 + 2020, followed by the summer maintenance team 2019/2020. The on-site operator team 2019 and onsite operator team 2020 showed the lowest values. The values presented in this paper indicate the need to
minimize crew time as well as workload demands of the operators involved in the operation of future planetary
surface greenhouses.
... Following the official end of the project, operation of the greenhouse facility was continued through a partnership between the German Aerospace Center (DLR) and the Alfred-Wegener-Institute (AWI). The EDEN ISS project background, design of the MTF, the initial set-up phase, and data and operation information from the 2018 through 2020 seasons have been published previously 1,2,3,4,5,6,7,8 . ...
THE EDEN ISS greenhouse is a space-analogue test facility near the German Neumayer Station III (NM-III) in Antarctica. The greenhouse design, construction, and test phase began in 2015, and the facility was shipped to NM-III in January 2018. From 2018 until early 2022, the greenhouse was in continuous operation during every winter-over period, with the 2021 season being the latest to be completed. The purpose of the facility is to enable multidisciplinary research on topics related to plant cultivation on future human space exploration missions. Research on food quality and safety, plant health monitoring, microbiology, system validation, human factors, horticultural sciences, and resource demand was conducted. During the 2021 season, research and operation of the EDEN ISS greenhouse was done as part of a DLR-NASA collaboration with an American on-site operator. Part of this collaboration was testing new crops like chili pepper, broccoli, cauliflower, and beans, which had never been grown inside EDEN ISS. These crops were complemented by a variety of lettuces, mustard greens, herbs, tomatoes, cucumbers, radishes, and kohlrabi. In total, approximately 315 kg of fresh produce was harvested during the 2021 season, which was supplied to the NM-III wintering crew. Frozen and dried plant subsamples were collected and transferred back to Europe and the United States for further investigation. Additional samples were taken from the nutrient delivery subsystem and from surfaces inside the EDEN ISS facility in order to continue the microbiological research activities from previous years. Another research focus was capturing crew time for all activities inside the MTF and select support activities inside NM-III to increase the understanding of work time demand for future food production systems in space. DLR and NASA also continued the numerous outreach activities of the past years. This paper summarizes both the research and the outreach activities during the latest operational season of the EDEN ISS Antarctic greenhouse in 2021.
... Table 1 Subdivision of plant growth related tasks for crew time recording. This is adapted from Stromgren et al. (2018) (Schubert et al., 2018;Vrakking et al., 2020). ...
Crew time requirements for human space exploration missions is as critical as mass, energy, and volume requirements. However, it has only been sporadically recorded in past analog and space missions for plant cultivation. In this retrospective study on crew time data collected in various analog facilities and on the Veggie hardware on ISS, we propose a methodology for efficient categorizing and reporting of crew time in space plant growth systems. Crew time is difficult to capture in operational environments, and this study intends to harmonize these efforts among different locations. This article also provides a current database for required crew time in several plant growth hardware and facilities, on the ISS, and on Earth. These data could serve mission planners, as a baseline to establish standardized activities and extrapolate crew time needed to operate future plant growth units. Finally, we discuss how crew time needed for plant cultivation will change in future exploration missions, based on choices made for plant species, watering systems, level of automation, and use of virtual assistants, among others. Crew time will need to be accounted for as a decisive factor to design future space greenhouse modules.
... 1). The production reached on August 2018 26 Kg of biomass and a yearly production of 268 kg (Fig.3, Vrakking et al., 2020). ...
The EDEN ISS project is the first European bio-regenerative system tested in Antarctica. The habitability impact on the crew emerged in term of both psychological and nutritional benefit, making an important contribution to the advancement of international research on bio-regenerative systems both for the exploration of the Universe and for Earth applications. Particularly, during the Crew 2018 and 2019 mission, the psychological and physiological impact of the plants on their well-being was assessed as positive by all crew members as also foreseen by the biophilia concept and presented in this paper. The investigation will be also be proposed at stations like Concordia in order to have a comparison crew without a greenhouse.
Digital Twins as a virtual entity of a physical system open up a variety of new opportunities. Their development on the other hand can be very challenging especially for complex systems. The EDEN ISS Mobile Test Facility with its Future Exploration Greenhouse belongs to those more sophisticated setups. During its operations since 2018 a great volume of data is collected which is including more than 200 sensors and a wide crew documentation. In this paper the development of a Digital Twin is approached by utilizing this data for machine learning. Specifically, a Neural Network is developed that recreates the same changes on the features of the dataset as the physical system did in the past. In the event of success the Neural Network is holding a general representation of the physical system and also future or virtual changes can be simulated. In particular, time series forecasting is chosen to perform the prediction making by taking the past 24 hours as input and returning the following 24 hours as an output, both in a 5 minute step resolution. The development starts by the preparation of the dataset, where individual data tables are merged, missing data is interpolated and constant or corrupted features are identified and removed. The general structure of the Digital Twin is divided into 3 sub-models to address categorical differences of the features. The first distinction is made according to the documentation style between the sensor data and the crew data, which is containing the information about the plants. A further differentiation is done inside the sensor data between time controlled variables and environment controlled variables whether the values are regulated by a time schedule or not. Those 3 sub-models are named time controlled model, environment controlled model and plant model. The identification of time controlled variables is carried out by sorting over the error term of a model that assumes a 24 hour periodic repetition. The remaining ones from this identification make up the environment controlled variables. The first sub-model, the time controlled model is developed by applying a whole group of models on this subset and selecting the model with the highest precision by the error term they created. The previous mentioned repetition model was selected which offered a very small error in prediction. The second sub-model, the environment controlled model is generally following the same approach. A smaller set of Neural Networks is applied on the new structure and again the best performing model is chosen for further investigation. The LSTM-model is offering the lowest error in prediction here and is expanded and regulated for a second training. Besides further improvement, this model is still ending up on a high level of error when averaged over all features. These errors in prediction vary greatly on the individual variables and range from decent precision up to a deterioration over the baseline. The development of the third and final sub-model, the plant model resulted to be unsuccessful. The insufficient amount and resolution of the plant data is missing the requirements for the intended objective of bringing the plants biomass in correlation with system values. In conclusion, the development of a Digital Twin for the EDEN ISS system is prototypically achieved, while the approach of building a Digital Twin without the system being designed for it encountered heavy limitations.
What a year, what a year! Who would have thought this?! The year 2020 marked the beginning of a global pandemic that impacted all areas of social- and professional life. Beginning of mid-March, DLR went into a complete lock-down, followed only by partial reopening during summer, entering a soft lock-down again in winter 2020. Although these extreme circumstances were not favourable, the operation of the EDEN ISS facility in Antarctica continued successfully, and multiple new research projects were initiated by the group throughout the year. Most notable is the collaborative science mission of NASA and DLR to jointly operate the EDEN ISS greenhouse. In December 2020, NASA scientist Jess Bunchek travelled to Antarctica. She operates the facility for the isolation campaign in 2021. A multifaceted research programme was worked out between NASA and the EDEN group, which includes e.g. cultivar testing, and crew time measurements. The year 2020 also marked a milestone for the EDEN group, by outlining the research and development goals for the next decade. The DLR roadmap for the development of bio-regenerative life support systems was officially published. The plan foresees the development of a 1:1 life support module by the year 2025 that will allow to test key cultivation technologies already on space-rated system design level. This will push the courageous ambition to have a flight-ready design by 2030 for a possible Moon deployment scenario.
The future of human space exploration is aimed at long-term missions to Moon and Mars. Currently, plans are elaborated by NASA, ESA, CNSA and others for a return to the lunar environment within the next decade as an intermediate step towards the goal of reaching the surface of Mars. For sustenance and crew comfort the crew of such long-duration missions should be provided with fresh food on the lunar or Martian surface. Due to the associated power demand, the required resources and technological complexity, this is a major challenge for this kind of missions. To continuously provide fresh food without the need for cargo transfer from Earth towards Moon or Mars an on-site greenhouse system is required, producing the fresh food in situ. The associated effort and cost for all resources to be transported to the base of operation prohibit any waste of resources, requiring a system operating in a (nearly) closed loop. Developing and validating a prototype for an effective and efficient greenhouse, labeled future exploration greenhouse (FEG) for space exploration has been the goal of the EDEN ISS project, funded by the EU, in the past 4 years. This paper shows the results of a design elaboration of the FEG into a greenhouse for planetary deployment on Moon or Mars. Guided by lessons learned from operating the FEG in Antarctica for one year and based on assumptions concerning the mission scenario, e.g. assuming an existing base infrastructure on-site, the presented design incorporates a plant growth area which is more than a factor of two larger than the prototype. The total mass of the cylindrical system, including equipment required during launch, transfer and landing, is about 19 mT, fitting into a Falcon 9 launcher. The versatile design is compatible with a wide variety of mission scenarios, e.g. ESA’s Moon Village, and currently public mission plans.
The EDEN ISS greenhouse, integrated in two joined containers, is a confined mobile test facility in Antarctica for the development and optimization of new plant cultivation techniques for future space programs. The EDEN ISS greenhouse was used successfully from February to November 2018 for fresh food production for the overwintering crew at the Antarctic Neumayer III station. During the 9 months of operation, samples from the different plants, from the nutrition solution of the aeroponic planting system, and from diverse surfaces within the three different compartments of the container were taken [future exploration greenhouse (FEG), service section (SS), and cold porch (CP)]. Quantity as well as diversity of microorganisms was examined by cultivation. In case of the plant samples, microbial quantities were in a range from 102 to 104 colony forming units per gram plant material. Compared to plants purchased from a German grocery, the produce hosted orders of magnitude more microorganisms than the EDEN ISS plants. The EDEN ISS plant samples contained mainly fungi and a few bacteria. No classical food associated pathogenic microorganism, like Escherichia and Salmonella, could be found. Probably due to the used cultivation approach, Archaea were not found in the samples. The bioburden in the nutrition solutions increased constantly over time but never reached critical values like 102–103 cfu per 100 mL in irrigation water as it is stated, e.g., for commercial European plant productions. The surface samples revealed high differences in the microbial burden between the greenhouse part of the container and the SS and CP part. However, the numbers of organisms (bacteria and fungi) found in the planted greenhouse were still not critical. The microbial loaded surfaces showed strong temporal as well as spatial fluctuations. In samples of the nutrition solution and the surface, the amount of bacteria exceeded the amount of fungi by many times. For identification, 16S rRNA gene sequencing was performed for the isolated prokaryotic organisms. Phylogenetic analyses revealed that the most abundant bacterial phyla were Firmicutes and Actinobacteria. These phyla include plant- and human-associated bacterial species. In general, it could be shown that it is possible to produce edible fresh food in a remote environment and this food is safe for consumption from a microbiological point of view.
The EDEN ISS project has the objective to test key technologies and processes for higher plant cultivation with a focus on their application to long duration spaceflight. A mobile plant production facility was designed and constructed by an international consortium and deployed to the German Antarctic Neumayer Station III. Future astronaut crews, even if well-trained and provided with detailed procedures, cannot be expected to have the competencies needed to deal with all situations that will arise during a mission. Future space crews, as they are today, will be supported by expert backrooms on the ground. For future space-based greenhouses, monitoring the crops and the plant growth system increases system reliability and decreases the crew time required to maintain them. The EDEN ISS greenhouse incorporates a Plant Health Monitoring System to provide remote support for plant status assessment and early detection of plant stress or disease. The EDEN ISS greenhouse has the capability to automatically capture and distribute images from its suite of 32 high-definition color cameras. Collected images are transferred over a satellite link to the EDEN ISS Mission Control Center in Bremen and to project participants worldwide. Upon reception, automatic processing software analyzes the images for anomalies, evaluates crop performance, and predicts the days remaining until harvest of each crop tray. If anomalies or sub-optimal performance is detected, the image analysis system generates automatic warnings to the agronomist team who then discuss, communicate, or implement countermeasure options. A select number of Dual Wavelength Spectral Imagers have also been integrated into the facility for plant health monitoring to detect potential plant stress before it can be seen on the images taken by the high-definition color cameras. These imagers and processing approaches are derived from traditional space-based imaging techniques but permit new discoveries to be made in a facility like the EDEN ISS greenhouse in which, essentially, every photon of input and output can be controlled and studied. This paper presents a description of the EDEN ISS Plant Health Monitoring System, basic image analyses, and a summary of the results from the initial year of Antarctic operations.
The EDEN ISS project partners deployed a space greenhouse analogue at the Neumayer Station III in Antarctica in January 2018. The greenhouse is incorporated in two interconnected 20 foot shipping containers and positioned around 400 meters away from the research station. All subsystems required for plant cultivation are inside this so called Mobile Test Facility. The cultivation area of around 12.5 m² is arranged in a shelf-like structure in one of the containers, while the other container houses the subsystems and a small working area. Between February and November 2018 one of the authors was the only on-site operator of the greenhouse. In that time it was his responsibility to cultivate various plants and to execute numerous experiments. One of the experiments was the determination of the crewtime required for plant cultivation. A formula to calculate the crewtime use inside a space greenhouse has been developed. This paper also presents crewtime values for various activities related to the operation of a space greenhouse. The focus is on the tasks related to plant cultivation such as sowing, pruning, harvesting and cleaning. Crewtime has been measured independently for different crop species, because each crop species requires different tasks to be performed during cultivation. Additionally, the task schedule and related crewtime of complete workdays have been documented at several occasions during the nine months of operation of the EDEN ISS greenhouse in Antarctica.
The international EDEN ISS project aims to investigate and validate techniques for plant cultivation in future bioregenerative life support systems. To this end the EDEN ISS project partners aim to design and build the Mobile Test Facility, which consists of two modified 20 foot shipping containers. One of these shipping containers is designated the Service Section and houses the bulk of the subsystem components, such as the Air Management System and Nutrient Delivery System, as well as a rack-sized plant cultivation system, which uses a standard International Space Station payload form factor. The subsystems within the Service Section ensure that the approximately 12.5 m² of cultivation area in the second container, the Future Exploration Greenhouse, have the proper environmental conditions, nutrients and illumination for optimal crop growth. The EDEN ISS project concluded its main design phase with a Critical Design Review in March 2016, thereafter proceeded into the hardware development and procurement phase of the project. This paper describes the final design of the Service Section at the start of the assembly, integration and testing phase, which will run until the complete Mobile Test Facility is shipped to Antarctica, where it arrives in December 2017, for a 12 month space analogue mission.
The Future Exploration Greenhouse (FEG) is the heart of the international EDEN ISS project, which aims to investigate and validate techniques for plant cultivation in future bio-regenerative life support systems. The EDEN ISS project partners designed and built the Mobile Test Facility (MTF), which consists of two modified 20 foot shipping containers. The FEG is integrated into one of these containers. It has a shelf-like plant cultivation system with up to four levels for growing plants and it has a cultivation area of roughly 12.5 m². The FEG is designed to accommodate different plant species ranging from leafy greens (e.g. lettuce, spinach) to tall growing plants (e.g. tomato, cucumber). The plants grow in customized trays which hold the plants in position and contain the plants' roots. The trays can be connected to one of the two nutrient solution supply lines, each line providing a different nutrient mix. All plants grow in the same atmosphere and water-cooled LED lamps provide the light energy for photosynthesis. The FEG design has evolved from early designs in 2014 over the preliminary design by the end of 2015 to the final design which is described in this paper. Following assembly, integration and testing, the complete MTF will be shipped in October 2017 to Antarctica, where it will arrive in December 2017 and undergo a 12 month space analogue mission.
Plant cultivation in large-scale closed environments is challenging and several key technologies necessary for space-based plant production are not yet space-qualified or remain in early stages of development. The EDEN ISS project foresees development and demonstration of higher plant cultivation technologies, suitable for future deployment on the International Space Station and from a long-term perspective, within Moon and Mars habitats. The EDEN ISS consortium will design and test essential plant cultivation technologies using an International Standard Payload Rack form factor cultivation system for potential testing on-board the International Space Station. Furthermore, a Future Exploration Greenhouse will be designed with respect to future planetary bio-regenerative life support system deployments. The technologies will be tested in a laboratory environment as well as at the highly-isolated German Antarctic Neumayer Station III. A small and mobile container-sized test facility will be built in order to provide realistic mass flow relationships. In addition to technology development and validation, food safety and plant handling procedures will be developed. This paper describes the goals and objectives of EDEN ISS and the different project phases and milestones. Furthermore, the project consortium will be introduced and the role of each partner within the project is explained.
The EDEN-ISS is a greenhouse project at the Neumayer Station III in Antarctica. For the first time, this greenhouse supplied the station with fresh food and enabled research regarding sustainable and autonomous food production from Earth to Space. To investigate the plants’ impact on the crew (biophilia), a debriefing, questionnaires, and behavioral observation were used. The results show that the crew was satisfied with the consumption of fresh vegetables, which are usually not available in Antarctica. All (9 of 9 crew members) also agreed on the positive psychological and physiological impact of the plants on their well-being. The investigation will be repeated with the next crew of the Neumayer Station III and will also be proposed for comparison at stations like Concordia.
Plant cultivation in large-scale closed environments is challenging and several key technologies necessary for space-based plant production are not yet space-qualified or remain in early stages of development. The Horizon2020 EDEN ISS project aims at development and demonstration of higher plant cultivation technologies, suitable for near term deployment on the International Space Station (ISS) and from a long-term perspective, within Moon and Mars habitats. The EDEN ISS consortium, as part of the performed activities, has designed a plant cultivation system to have form, fit and function of an European Drawer Rack 2 (EDR II) payload, with a modularity that would allow its incremental installation in the ISS homonimous rack, occupying from one-quarter rack to the full system. The construction phase is started, and the developed system will be tested in a laboratory environment as well as at the highly-isolated German Antarctic Neumayer Station III, in a container-sized test facility to provide realistic mass flow relationships and interaction with a crewed environment. This paper describes the goals and system general design status of EDEN ISS ISPR plant growth facility.
Biomass Production of the EDEN ISS Space Greenhouse in Antarctica during the 2018 Experiment Phase
- P Zabel
Zabel, P., et al., "Biomass Production of the EDEN ISS Space Greenhouse in Antarctica during the 2018 Experiment
Phase," Frontiers in Plant Science, Vol. 11, Art. 656, May 2020, doi: 10.3389/fpls.2020.00656
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