Spinal Elongation and its Effects on Seated Height in a Microgravity Environment (Spinal Elongation) - 07.29.14
ISS Science for Everyone
Science Objectives for Everyone
The Spinal Elongation and its Effects on Seated Height in a Microgravity Environment (Spinal Elongation) study provides quantitative data as to the amount of change that occurs in the seated height due to spinal elongation in microgravity.
Science Results for Everyone
Johnson Space Center, Human Research Program, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Human Exploration and Operations Mission Directorate (HEOMD)
ISS Expedition Duration
March 2009 - September 2011
Previous ISS Missions
This will be the first mission for Spinal Elongation.
- Spinal elongation due to microgravity is an important consideration for the seated height dimension. Past research has demonstrated that crewmembers tend to increase in stature by up to 3 percent, which has driven current requirements to allow for such growth in dimensions such as stature and seated height.
- The Spinal Elongation and its Effects on Seated Height in a Microgravity Environment (Spinal Elongation) study will provide Crew Exploration Vehicle (CEV) designers the accurate anthropometry (measurement of the size and proportions of the human body) data needed in order to ensure that the vehicle accommodates the full range of crewmembers. Seated height measurements are of particular interest due to the nature of seat layout within the vehicle.
- The criticality of this measurement is such that changes in seated height on the order of magnitude of inches have significant impacts on the level of crew accommodation available.
The Spinal Elongation and its Effects on Seated Height in a Microgravity Environment (Spinal Elongation) investigation provides quantitative data about the amount of change that occurs in the seated height due to spinal elongation in space. Spinal elongation has been observed to occur in crewmembers during space flight, but has only previously been recorded in the standing position. The seated height data in microgravity is considered necessary to correctly identify the seated height projections of the crew in the Orion configuration. The projections of seated height will provide data on the proper positioning of the seats within the vehicle, adequate clearance for seat stroke in high acceleration impacts, fit in seats, correct placements of seats with respect to each other and the vehicle and the proper orientation to displays and controls. Additionally, data concerning the effects of spinal elongation on seated height would aid in the design of suit components, habitation requirements and tool specifications of future long-duration space expeditions.
Changes in seated height due to spinal growth will be assessed based on measurement with an anthropometer (instrument for measuring the human trunk and limbs) as well as scaling of objects of known sizes in photographs of seated crewmembers. These methodologies, which have been tested in the laboratory and the Space Shuttle cockpit trainer, were selected as the most accurate means available during flight. Measurements will be taken at pre-defined intervals during flight for each crewmember.
The process will involve manual measurements as well as setting up a camera mount according to instructions. For each set of measurements, the crewmember will restrain him/herself into the commander seat while another crewmember assists by measuring the distance from the top of the seat to the top of the subject’s head and taking a photograph using pre-defined camera settings.
This seated height data in microgravity is considered necessary to correctly identify the seated height projections of the crew in the Orion configuration. Correct projections of seated height should lead to proper positioning of the seats within the vehicle; adequate clearance for seat stroke in high acceleration impacts; providing proper fit in seats; proper placement of seats with respect to each other and the vehicle; and proper orientation to displays and controls. Additionally, data concerning the effects of spinal elongation on seated height would aid in the design of suit components, habitation requirements and tool specifications.
This study will provide information on spinal elongation and compression for people who suffer from back pain on Earth.
This study requires twenty-three subjects from both long-duration International Space Station subjects and short-duration Space Shuttle subjects. One preflight baseline data collection session will take place at any time after informed consent is obtained from the subject. At least one measurement is to be taken on orbit after the subject has been in orbit for 48 hours. Measurements taken later in the mission are highly desired. More than one session per subject is also highly desired to improve the science data. These measurements consist of photographs and data from the anthropometer. A postflight baseline data collection session will take place at any point within thirty days of landing.
During the flight, the commander seat will be placed in entry configuration, and the test operator will remove the seat pan cushion, parachute, and head rest from the seat. Camera settings will be configured according to a set of provided instructions, standardizing settings such as aperture and focus. The test operator will position the camera using a multi-bracket assembly installed on a camera shoe near the pilot seat. The camera position will be adjusted such that it is orthogonal to the commander seat by adjusting the multi-use bracket and using the pilot seat as a reference point, also ensuring that the subject’s entire profile is captured in the frame. The pilot seat’s seatback, set at the same angle as the commander seat’s seatback, may be used as a guide to position the camera orthogonal to the subject. The test operator will retrieve and assemble the anthropometer, affixing the base to the top of the commander seat. The base will ensure that the anthropometer is in the proper standard location, extending along the line of the seatback upward and behind the subject’s head. The position will be consistent between trials due to the design of the anthropometer’s base. The subject, wearing light-weight clothing, will be seated in the commander seat. The test operator will assist the subject in adjusting the lap belt to ensure that positive contact is made between the subject and the seat pan. The subject will sit with his/her back and neck straight, with the shoulders resting against the seat back, and gaze directly ahead at a reference object. Training before flights should assist with consistency for this posture. The anthropometer will be used to measure the distance from the top of the seat to the top of the subject’s head, the measurement will be recorded in the procedure log, and a photograph will be taken of the subject. The crewmember will exit the seat, and will repeat to gather the second set of data points. Each session involves two values recorded in procedure log and two photographs taken.
My How You’ve Grown
Operational sketch of Spinal elongation operations.
+ View Larger Image