More than 40 large, human-made, uncontrolled objects reenter Earth's atmosphere every year, with 10 - 40 percent of that object's mass actually striking the ground. While most of this debris falls harmlessly in the ocean or uninhabited areas, there is a measurable risk to people and property, especially in cases where a failure results in reentry in an unintended manner. Lacking an ability to collect first-hand data during a reentry, our knowledge of how reentry and breakup occur is limited. Better data is needed to improve the prediction models of the reentry safety, scientific research, and spacecraft design communities. Learn more ►
RED-Data addresses the need for collection of better reentry data. RED-Data is a basketball ball sized device, weighing approximately 8 kg, encased in a heat shield that rides with a host vehicle to space, records detailed data during a reentry event, and sends that data to a PC via the Iridium satellite network before hitting the ground.
- Offers significantly improved quality of data at lower cost than currently employed radar and air observation methods
- Reduces time and effort required to reconstruct reentry details after the event
- Enables calibration of prediction models for more accurate safety calculations
- Facilitates "design for demise" efforts for expendable launch vehicle stages and spacecraft, whereby launch vehicle stages and spacecraft are intentionally designed to more fully disintegrate during reentry
- Facilitates design for safe reentry and recovery for reusable crew and cargo spacecraft
Typical instruments of a RED-Data unit include the following. The instrument set may be customized according to customer needs.
|2-g three axis accelerometers||Detects reentry to activate the device|
|200-g three axis accelerometers||Measures accelerations during reentry|
|Rate gyro||Measures angular rates about three axes|
|Pressure sensors||Measures pressure internal to the device|
|GPS receiver||Captures altitude, velocity, and time|
|Temperature Sensors||Embedded at several locations on the heat shield|
|Dimensions||36 cm diameter X 28 cm high|
|Heat Shield||Conformal Ablative TPS|
RED-Data is an elegant solution for gathering reentry data, combining well understood aerospace with innovative packaging. The RED-Data unit consists of an electronics assembly packaged in an aeroshell and heat shield. The unit is mated to a host vehicle through use of a copper housing. During reentry of the host vehicle, the RED-Data is released from its housing by the high heating environment.
Cost of the electronics assembly is reduced through use of off-the-shelf components, and by leveraging the existing Iridium communication and GPS networks. Low-g accelerometers are used to fully activate RED-Data when reentry is sensed, thereby minimizing power requirements.
The aeroshell is a 45 degree sphere-cone shape pioneered at NASA for the Mars Microprobe (Deep Space 2) mission by Dr. Robert Mitcheltree and Terminal Velocity CTO Dr. Robert Braun. The shape is specifically designed to fall in a predictable and stable orientation, which allows the internal communications devices of RED-Data to point skyward toward the supporting satellite networks.
The heat shield for RED-Data is fabricated using a conformal ablative thermal protection material. This material was invented and tested at NASA Ames Research Center for high temperature planetary entry applications. TVA has a non-reimbursable space act agreement with NASA Ames for collaboration and use of this technology.
RED-Data traces its heritage to the ReEntry Breakup Recorder (ReBR) developed at The Aerospace Corporation. The ReBR was first successfully test flown on March 29, 2011 aboard a Japanese H-II Transfer Vehicle (HTV). The HTV mission is to deliver cargo to the International Space Station. It then is intentionally deorbited and destroyed as it reenters the Earth's atmosphere. ReBR rode along with the HTV-2 during reentry, successfully completing all of its data collection and transmission objectives. Two more ReBR units were subsequently sucessfully test flown aboard another HTV and the European Autonomous Transfer Vehicle (ATV).
TVA's RED-Data product benefits tremendously from the excellent engineering conducted at the Aerospace Corporation to demonstrate the concept of reentry breakup data collection. Recognizing the value of this heritage, TVA has exclusively licensed the ReBR technology from the Aerospace Corporation, and it serves as the basis for RED-Data.