Out of Space


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Industrial Engineer- Volume 43 Number 2

Using RFID, simulation and other IE methods to control inventory for NASA

In 2004, astronauts onboard the International Space Station (ISS) nearly had to their outpost because consumables replenishment was uncertain. Researchers at the RFID Supply Chain Lab (RFSCL) in the University of Nebraska’s Department of Industrial Engineering decided to tackle this problem. After this accident occurred, space missions were postponed due to investigation. Astronauts aboard the ISS were instructed to reduce their daily calorie intake by approximately 300 calories.

A high level of inventory accuracy is critical for NASA astronauts to survive in space. After the inventory issues, NASA had to re-evaluate inventory control policies to ensure that future astronauts would not be forced to eat less when inventory is not available. Astronauts onboard the ISS use manual auditing and barcode scanning to track perishable inventory, which presents a challenge because periodic inventory audits are labor intensive, time consuming, and many provide inaccurate measures. Currently, researches are investigating “automated inventories”, which allow for inventory audits to occur remotely without the need for human inventories.

The EOQ is the number of units an organization should add to inventory with each order minimizing the total costs of inventory. The researches seek to use traditional EOQ techniques to support NASA inventory. Currently, NASA uses manual counting and barcode techniques to track items such as crew clothing, office supplies and hygienic supplies at the bag level, but not at the item level. The research team is investigating the use of RFID technologies to eliminate the manual tasks associated with the aforementioned techniques. Planned results include an RFID systems that allows for “crew-free” automated inventories that require astronauts minimal time and labor to reduce excessive. RFID technologies were considered expensive and limited, but as the tags, readers and the associated equipment costs continue to decrease, a growing number of organizations have begun to explore the feasibility of using RFID systems. RFID can also be integrated with real-time location systems (RTLS) to identify and locate items. RFID technology works through electromagnetic communication between a reader (interrogator) and a tag (transponder).

Several steps were conducted in order to determine an RFID-based EOQ model that would allow for more accurate replenishment scheduling. The model develop for NASA consumable food planning policy consists of the following five-steps approach:

  1. Calculate the calories consumed by astronauts.
  2. Construct a simulation model that determines the annual amount of food consumed by (astronauts food consumption about the ISS, simulation was used to estimate the ISS’’s annual demand for food).
  3. Determine safety stock values.
  4. Integrate the annual demand and the costs into an EOQ model to determine the optimal quantity.
  5. Run a sensitivity analysis that varies demand and cost. Using RFID to automate inventory counts and location of inventory. NASA recently installed and RFID system at its Langley Research Center in Langley, VA, to take inventory of important data center and lab assets such as servers and switches.


Astrid Hanny Apsari (1401110715)

Gamma Febriyandi (1501195043)

Hikmah Yulia (1501186083)

Kelvin Thanaka (1501185944)

Ryan Reinaldo (1501185894)