The Agricultural Camera (AgCam) takes frequent images, in visible and infrared light, of vegetated areas on Earth; primarily crops, rangeland, grasslands, forests, and wetlands in the northern Great Plains and Rocky Mountain regions of the United States. Requesting parties (e.g., farmers, ranchers, foresters, natural resource managers, tribal officials, and educators) directly receive images within 2 days of requests, which helps them improve environmental stewardship. Students and faculty at the University of North Dakota, Grand Forks, ND, chiefly built and operate the AgCam.Principal Investigator(s)
University of North Dakota, Grand Forks, ND, United States
National Aeronautics and Space Administration (NASA)Sponsoring Organization
NASA Education (EDU)Research Benefits
Information PendingISS Expedition Duration:
March 2009 - March 2010Expeditions Assigned
19/20,21/22Previous ISS Missions
ISS Expedition 19/20 was the first attempt to operate AgCam.
Agricultural Camera (AgCam) is a multispectral camera destined for use on the ISS as a payload of the Window Observational Research Facility (WORF). Primary AgCam system components include an Imaging System Assembly, a Base Mount Pointing Assembly, a Power/Data Controller, associated cabling and support items, and a NASA-supplied A31p Laptop and power supply.
Current Earth remote sensor platforms typically collect data too infrequently for rapidly changing short-season northern crops, which are frequently under cloud cover, or deliver data with too much latency for effective in-season decision support. Those sensor platforms that can meet the preceding needs have spatial resolutions that are too coarse for evaluation of in-field variability. AgCam enables users the selection of specific geographical areas of interest and the ability to request acollection of AgCam imagery in both red and near-infrared bandpasses at medium-high spatial resolution. The AgCam sensor can point up to 30 degrees off-nadir, enabling frequent (i.e., multiweek to multiday) imaging of a requested area, dramatically improving chances of obtaining cloud-free images. Collected images will downlink to the ground for processing and then deliver to the requesting end users within 1 to 2 days of image collection.
Farmers using variable-rate application and other precision agriculture techniques will be able to dynamically delineate management zones as the crop vegetation canopy changes during the growing season; this can result in more effective use of fertilizer and other chemical inputs and reduce negative environmental effects. Further, crop canopy reflectance in AgCam spectral bands correlates to nitrogen concentrations in the plant biomass; knowledge of variations in plant nitrogen across fields can help improve in-season nitrogen application decisions. Ranchers can also benefit from AgCam, by evaluating rangelands livestock carrying capacity. This knowledge can help ranchers avoid ecosystem damage due to overgrazing and erosion. Rapid delivery of imagery for these and other applications will enable management decisions during current season's operations.
The Base Mount Pointing Assembly provides a solid mounting to the internal WORF payload support shelf, incorporating a slide mechanism to facilitate crew setup and activation. An integral gearbox and controller points the lens assembly up to 30 degrees cross-track. Inside the Power/Data Controller, frame grabber cards within a PC expander bus collect imagery from the cameras and forward it to AgCam software, which runs in a standard ISS A31p Laptop that connects via a PCMCIA cable. A built-in power converter individually powers on the controller and cameras.
Within the Imaging System Assembly, an Isolation System Mount uses a tuned passive visco-elastic system to provide the vibration isolation and absorption needed to prevent excessive jitter in the AgCam images. A single 300 mm lens and optical beam splitter supply light to two digital line-scan cameras, each with its own filter: red (630 to 690 nm) and near infrared (780 to 890 nm). Healthy vegetation is highly absorptive in this red band (R) and highly reflective in the near-infrared band (NIR); combining them via ground data processing into a Normalized Difference Vegetation Index (NDVI), where NDVI = (NIR - R)/(NIR + R), yields a highly responsive indicator to reductions in plant health, whether from reduced chlorophyll production (i.e., increases R reflectance) or from heat/drought stress-induced stomata closure (i.e., decreases NIR reflectance).
Nominally, ground uplink provides command for payload operations. Commands store in an onboard command queue and execute based on ISS-supplied system time. Collected imagery downlinks via the low-rate payload Local Area Network (LAN). Alternative operations allow for crew-initiated imagery collection using crew interface software running on the WORF laptop.
AgCam is a space-related research project that provides direct benefits from space to the general public. Increasing the relevance of space-related research activities in the daily lives of the general public will benefit all ISS applications, whether for space or Earth applications. By using AgCam data in support of precision agriculture activities, the public will receive benefits synergistically from three different space systems: (1) Earth-observing from the ISS, (2) in-field navigation from the Global Positioning System (GPS), and (3) data delivery via satellite communications. With respect to the educational aspect of the AgCam project, using students to develop and operate AgCam helps train the next generation of scientists and engineers that will work on future space-based applications.Earth Applications
Anticipated benefits from AgCam data and information products imagery include nitrogen application maps for efficient fertilizer use, agriculture management zone decision support systems for nutrient and invasive species management, and rangeland management tools to improve livestock allocation and evaluation. The rapid responsiveness of AgCam imagery may also aid in disaster management applications, such as flood monitoring and wildland fire mapping.
To image the Earth, AgCam requires the ISS to be in Local-Vertical-Local-Horizontal (LVLH) orientation, and requires the US Laboratory Window external shutter to be open. Typically, imaging operations occur only when the ISS is over the northern central region of the United States, though imagery can be collected throughout all ISS orbits whenever the Earth surface below is in daylight. Frequency and location of imaging is highly dynamic, driven by needs of a wide variety of end user research partners, but is much more extensive during the growing season of the northern plains (April - October). At peak times, 2-4 images per orbit for 4 consecutive orbits are anticipated; several hours of powered operations immediately following collection is required to complete image downlink.Operational Protocols
Prior to arrival and installation of the WORF, adaptive AgCam components enable installation of AgCam directly onto the U.S. lab window frame. Crewmembers install AgCam components, including an A31p Laptop and other GFE equipment, into the internal volume of the WORF. Nominal operations of AgCam do not require crew support, after setup and activation of AgCam, other than manual opening and closing of the Lab Window external shutter per standard flight rules. From within the AgCam Science Operations Center at the University of North Dakota, operators receive AgCam imagery requests from an extensive network of end-user research participants. Operators then convert these requests into specific sets of commands for uplink to AgCam. Through coordination with NASA for WORF rack operations, image acquisition and other AgCam operational commands are uplinked to the AgCam payload software, which takes images over specific areas of the Earth. The resulting imagery data downlinks and transfer to the University of North Dakota for processing and quick delivery to image requestors. As a contingency plan, AgCam crew interface software is installed on the WORF Rack laptop. This allows crewmembers to initiate AgCam image collection based on their own or NASA's needs, without opening the WORF internal volume hatch cover. If necessary, the Earth Knowledge Acquired by Middle School Students (EarthKAM ) investigation can simultaneously operate from within the WORF volume with AgCam.
Agricultural Camera (AgCam name used historically from 2005 - 2010, later version known as ISSAC) was originally installed onboard the ISS over the US Lab Window in May 2009. This was prior to the launch and installation of the Window Observational Research Facility (WORF).
On May 31, 2009, during the first execution of the AgCam TAKE_IMAGE command (which initiates image acquisition), an in-flight anomaly occurred. The ISS crewmember re-secured a loose cable connection, yet the anomaly continued to occur. The anomaly manifested itself as an intermittently random failure to successfully take images. Over the next five months an extensive troubleshooting and failure analysis effort was undertaken. Troubleshooting efforts reached the conclusion that the intermittent random failure was isolated to an internal electronics hardware problem within one AgCam component, the Power/Data Controller (PDC). Crewmembers deactivated and stowed the AgCam payload on November 13, 2009 (Olsen 2009).
An upgraded sensor has since been developed that both eliminated the interface problem and significantly improved the science performance of the system by adding a third band to increase its spectral resolution. The remainder of the onboard and ground equipment functioned well and has been re-used in the new investigation, which is known as the International Space Station Agricultural Camera (ISSAC). Olsen D. Agricultural Camera Increment 19/20 Post-Flight Report, Nov 18, 2009.