# Presentation: 821022

## Earth Science Vision:Platform  Challenges

***Earth Science Vision:******Platform  Challenges***

- Speaker:  	Loren Lemmerman
- Contributors: 	Kul Bhasin, GRC
- 		John Bristow, GSFC
- 		Robert Connerton,GSFC
- 		Kevin Delin, JPL
- 		Fred Hadeagh, JPL
- 		Michael Lou, JPL
- 		Michael Pasciuto, GSFC

**lemmerman:**
***Key points:***
***Acknowledge contributors***
***Point out that this is really an overview to give some insight as to priorities for platform investments.***
***Then point out what a platform really is:  the system that provides support, comm and maintenance for instruments***

## Current EOS Vantage Points 

**Science Processing Center **

**Science Processing Center **

***Current EOS Vantage Points ***

*** ******Current EOS Vantage Points ***
***LEO Orbits  (typically 705 km)***
***GEO orbits ***

**lemmerman:**
***What you were told yesterday is that there is a  new approach being planned in ESE that contrasts significantly from today’s situation, represented here.***
***Whereas today, each mission exists primarily as an independent activity, ...  ***

## Future EOS Vantage Points 

***Future EOS Vantage Points ***

*** ******Future ESE mission will be integrated and will leverage multiple  vantage points ***
***Submersible***
***In Situ***
***Aircraft***
***Balloons***
***LEO Orbits***
***MEO***
***GEO orbits***
***Lunar***
***Libration points ***

**Science Processing Center **

**lemmerman:**
***...******in the future, observations will  be done by systems which are co-dependent.   This cartoon is an attempt to represent that codependency, and shows some of the variability anticipated.***

## Platform Challenges are Multi-dimensional

***New orbits ***
***Greater pointing accuracy Large structures ***
***Formation Flying***
***Station keeping***
***Precision control***
***Sensor Web challenges***
***Space-based***
***Airborne based***
***Surface based***
***Subsurface based***
***Micro s/c***
***Autonomy***

**lemmerman:**
**The ese vision is already being supported by significant new advancements in sensor technology**
**What is required is commensurate capability in the platforms supporting these advanced sensors **
***There are three distinct dimensions of the platform challenge:***
***1.  We will be flying many more constellations of s/c to accomplish a challenging measurement.  This type of formation flying typically demands precision control on the platform elements.***
***2.  We are also talking about observing from new  orbits.  This creates a totally new set of requirements, different from the precision formation flying.***
***3.  Finally there is the rather new concept of integrated sensing systems consisting of surface / airborne/ and space assets working together as an integrated sensing system.***
***What I will do, given the time constraints,  is to give examples of challenges in each of these areas.***

## High Orbit Platform Challenges

***GEO ***
***Driven by physics, large apertures are required***
***Large Lightweight Power Systems***
***Precision Pointing Knowledge***
***Precision orbit control***
***L2 (Occultation)***
***Absolute pointing of 1 arc-sec***
***Knowledge to .25 arc-sec***
***Jitter <.5 arc-sec/sec***

*Today: 12 m  dia*

*Future : 30 m  dia*

**lemmerman:**
***I mention these in passing .  Much more information on GEO SAR will be given later in papers this morning***

## Formation Flying

***Formation Flying***

***Formation flying implications***
***Autonomy ***
***Advanced GN&C ***
***Precision metrology***
***Challenge***
***achieve and then maintain a geometrical configuration (a virtual structure) without human intervention***
***Provide precision metrology in the nanometer range ***
***Example***
***For Gravity Field Mapping (EX-5/Grace Follow-on), position knowledge in the order of 100 nanometers will be required.  ***

**lemmerman:**
- Challenges in formation flying are represented here.

## Sensor Web Integration

**lemmerman:**
***Here is a bit more data on the sensor web concept.***
***The idea is that each type of observation is best suited to some specific type of observation area.  Sensor webs help to map to those strengths.***
***1.  You already have heard about plans for s/c to act in some communal sense.***
***2.  The objective is to allow airborne assets to examine specific areas identified by s/c in more depth, ***
***3.and then to  rapidly deploy a surface system to examine a portion of the airborne scanned area in even more detail and over a longer time period.***

## Sensor Web IT/Comm Technology Needs 

_***ESE Vision Feature***_
***Global Coverage  ***
***Low data latency***
***Retargeting ‘0n-the-fly’***

_***Platform advancements required***_
***Multiple Collaborating Assets***
***Formation flying for sparse apertures and rapid data delivery***
***Information and command links to suborbital sensors***
***Autonomous operations for affordability***
***Flexible communication systems***
***High Rate Communications***
***IP Based data distribution***
***Demand access-like communication***
***On-board data processing***
***Science Feature identification***
***Dynamic replanning ***
***Goal Driven Commanding***

**lemmerman:**
- To allow all those collaborations to happen, there are a number of technologies required dealing with on board processing, data extraction, autonomy, etc, and the demands are highly specialized, depending on the specific platform in question.

## Sensor Web Communications

## Challenges Summarized

**Communications**** ****- Ultra-high bandwidth**
**Seamless s/c to ground.  Essentially zero latency**
**GN&C**** ****- Precision autonomous control (nanometer scale)**
**Wave-front control across platforms for distributed instruments**
**Large, lightweight  Structures**** ****- 30-50 m class mw apertures**
**Sensor Web ****- Large scale self-maintaining architectures**
**C&DH**** ****- On-board processing for object /event recognition, data compression, instrument control,autonomy**
**Propulsion ****- Micro propulsion for precision station-keeping**