DRAFT – Wed



DRAFT – Wed. 9/29 2:02 a.m.

4. Statement of Justification

The work proposed herein addresses several issues critical to and unique to OExS. This work pertains especially to several key aspects of Spiral 2, human lunar return by 2020.

The enabling technology we propose is software-defined radio (SDR). This is a communications hardware/software platform in which the radio frequency (RF) signal is generated or received directly by a digital signal processor (DSP), so that the translation to/from baseband is defined in software. This provides the capability to change modulation and encoding on the fly, with consequent capability to perform sophisticated tradeoffs impossible or prohibitively expensive with a conventional RF front-end. An SDR transceiver can, in principle, communicate with virtually any other type of transceiver, so that evolving technology no longer renders older equipment obsolete, and newer encoding and modulation techniques can be implemented without replacing hardware.

The application of software defined radio (SDR) to space telecommunications directly addresses the issues of affordability and sustainability, which are identified as the first key objective in the H&RT Formulation Plan. Software-defined radio also provides flexibility, as well as reusability, modularity, and reconfigurability, all of which are key strategic technical challenges identified in Section 6.4 of the Formulation Plan. This is identified in the BAA in Appendix A, Section 1.3 as being of interest to the Communications, Computing, Electronics and Imaging (CCEI) Element, specifically in the Space Communications and Networking Theme. A stated goal is " ... to achieve sustainable, scalable, fully accessible and fully reliable and secure communications and networking infrastructure within the solar system for multiple robotic and human assets wherever they are deployed. " Furthermore, one of the technologies specifically named is "software radio based technologies for flexible, energy efficient, multi access applications."

We propose to apply SDR specifically to robotic / human networks, which may contain members physically widely separated. This results in "limited human oversight due to distance," which is a challenge identified in the Formulation Plan as "unique to NASA" (Ref. Section 7.2.7). In the BAA, this is identified in Appendix A, Section 1.4, which describes the interest on the part of the Software, Intelligent Systems, and Modeling (SISM) Element in the areas of Autonomy and Intelligence and Multi-Agent Teaming, specifically " multi-robotic teams constructing planetary or orbital facilities."

5. Proposal Abstract

Project Description

The scope and aim of the proposed project is to develop a simulated interplanetary exploration environment in which a laboratory-based heterogeneous colony of cooperative robots interact, enabled by software radio. Communication latency will be introduced artificially to mimic time delays consistent with interplanetary missions. Members of the colony will be use a variety of communication modes in order to simulate a realistic scenario useful to NASA in which communicating entities most likely will not be equipped with identical transceivers.

We propose to build on our current expertise in the areas of software radio and cooperative robotics to develop a cooperative autonomous assembly and exploration system in support of NASA exploration goals in the H&RT program. It is envisioned that the communication infrastructure based on software radio will enable "plug and play" functionality, so that insertion or deletion of specific communicating entities into the communication scheme will be transparent.

The specific H&RT Formulation (Section 6.4.2) Strategic Technical Challenges addressed by this proposal are:

1. Robotic Networks

2. Modularity

3. Autonomy

4. Margins and Redundancy

5. Data-Rich Virtual Presence

Project Goals:

Goal 1: Establish an interactive network (colony) of at least three and potentially as many as twenty robots equipped with software radio communications capability

Goal 2: Identify key features and protocol necessary to mimic the interplanetary exploration environment from a communications standpoint as realistically as possible.

Goal 3: Use the testbed to develop and refine algorithms necessary to eventually accomplish specific tasks, such as assembly of mechanical parts, spacecraft docking, surface exploration, and others as suggested by NASA sponsors.

H&RT Goals and Objectives Supported:

1. Space Backbone Networks and Space Wide Area Networks (Communications, Computing, Electronics, and Imaging - CCEI). This project will enable the interaction of numerous autonomous entities over both short distances and interplanetary distances.

2. Multi-Agent Teaming (Software, Intelligent Systems, and Modeling - SISM). This project will enable multiple entities to cooperate on tasks over distances ranging from short range (a few meters) to interplanetary.

Technology Maturation Approach, Challenges, and Teaming

This project will begin at a TRL of 2 (Concept formulation) and end at TRL 4 (Laboratory breadboard). The development of the proposed robot colony will begin with a paper study to identify the key components required in consultation with the team members and NASA sponsors. Key expected obstacles include:

(1) Identifying the operating frequency band(s) and modulation methods most suited to the target application

(2) Implementing the necessary electronics in the limited size, weight, and cost constraints necessary for the laboratory testbed environment.

(3) Adapting existing protocols to accommodate latencies varying from microseconds to hours due to the need to interact over distances ranging from a few meters to interplanetary distances.

Technology Maturation:

The most likely road to technology maturation is through the Advanced Space Operations Technology (ASO) program element, although there is considerable potential through the Lunar and Planetary Surface Operations (LPSO) program element as well. In particular, the proposed research can contribute to ASO in the areas of in-space assembly, autonomy, reconfigurability, and data-rich virtual presence, and can contribute to LPSO in the areas of intelligent and agile surface mobility systems, surface manufacturing and construction systems, and surface environmental management.

Teaming:

The project will be directed by Dr. Thaddeus Roppel (Lead, Auburn University Sensor Fusion Laboratory). Dr. Roppel and Dr. Agrawal (Co-Lead, Wireless Research Center, Auburn University) will be primarily involved with software radio implementation, including firmware and software development. Dr. Wilson (Co-Lead, U. of Washington) will contribute expertise from the area of distributed architecture implementation, both software and hardware, as well as robotic systems. Dr. Bradley (Co-Lead, NASA LaRC) will contribute in the area of robotics, telerobotics, NASA goals, and NASA policies and procedures.

Impact on Future Exploration Systems

Exploration systems of the future will undoubtedly involve multiple vehicles fanning out over planet surfaces, together with numerous manned and unmanned entities in orbit or in transit between planets. In any conceivable scenario, it will be of the utmost importance for each entity to have the ability to communicate with all or a subset of the others with high reliability. Furthermore, tasks such as exploration, assembly, and inspection will need to be accomplished through cooperation and will require highly flexible "plug and play" communication systems as proposed here.

6. Project Description

a. Description of the proposed technology project including specific goals and objectives by phase and contract period.

The proposed project is the development of a simulated interplanetary exploration environment in which a laboratory-based heterogeneous colony of cooperative robots interact, enabled by software-defined radio (SDR). Communication latency will be introduced artificially to mimic time delays consistent with interplanetary missions. Members of the colony will use a variety of communication modes in order to simulate a realistic set of scenarios useful to NASA.

Relationship between the proposed work and the research emphases defined in the BAA (Appendix A)

$COMPLETE TABLE HERE

|PROPOSED TASKS |BAA Research Emphases |Relationship |

| | | |

| | | |

Phase 1:

In Phase 1 (12 months), we intend to design and build at least 4 prototype SDR boards (allowing for some design flexibility at the hardware level) using COTS components and install them on one fixed and two mobile robots or small rovers, as well as at a master station with human interface. We plan to implement a relatively simple digital modulation scheme, most likely $JAEGER at low bit rate $JAEGER. We will conduct several types of experiments and demonstrations, including variable-delay control loops, intelligent real-time adjustment of communication parameters, and translation- using an SDR to bridge a link between two other colony members using different protocols.

Phase 1 Goals:

1. Demonstrate, through a small-scale effort, the benefits of software-defined radio applied to human and robotic networks.

2. Demonstrate the capability of our team to organize and manage the proposed work effectively, and to deliver the promised work product.

3. Lay the groundwork for the Phase 2 effort.

Phase 1 Objectives:

1. Have in place an operational four-node human / robotic network communicating with software-defined radio.

2. Have in place a working demonstration of two simple, NASA-relevant cooperative activities within the colony which could not be achieved effectively without employing SDR: (i) intelligent real-time adjustment of communication parameters to overcome channel degradation, and (ii) translation- using an SDR to bridge a link between two other colony members using different protocols.

3. Have a design for new DSP boards for Phase 2, Year 1 essentially finished.

Phase 2:

In Phase 2 (36 months), we intend to enlarge the human-robotic network from Phase 1 to include at least 2 human-interface nodes, 2 stationary robotic nodes, and 3 mobile robotic nodes (the latter to be delivered by team member Langley Research Center). This will provide a reasonable level of complexity to investigate the scenarios of interest, while not being excessively expensive to construct or maintain. Improved SDR boards designed during Phase 1 will be fabricated and installed at each node. We will establish a design cycle for SDR boards to take advantage of new DSP technology as it becomes available. We anticipate obtaining new DSP's near the start of each contract year, and redesigning the SDR to take advantage of their increased throughput.

The complexity of the tasks to be demonstrated will increase each year in Phase 2. A final year task which can serve as a point of discussion would be cooperative assembly of a structure under remote (large time delay), minimal human guidance.

Phase 2 Goals:

1. Demonstrate the benefits and optimal usage of software-defined radio applied to human and robotic networks.

2. Establish a permanent testbed for experiments in software defined radio – enabled cooperative robotics which would be available for the benefit of NASA and the general use of the scientific and technical community.

Phase 2 Objectives:

1. Have in place an operational seven-node human / robotic network communicating with software-defined radio.

2. Have in place a working demonstration of cooperative assembly of a structure under remote (large time delay), minimal human guidance.

3. Have in place a working demonstration of a servicing operation in which a rover on a planet surface is to be serviced by a newer, SDR-equipped machine. The scenario requires the two to communicate, and requires some remote human intervention.

b. Description of the technology development/maturation approach, including, specific technical challenges that you expect to encounter, and technology metrics.

The most likely road to technology maturation is through the Advanced Space Operations Technology (ASO) program element, although there is considerable potential through the Lunar and Planetary Surface Operations (LPSO) program element as well. In particular, the proposed research can contribute to ASO in the areas of in-space assembly, autonomy, reconfigurability, and data-rich virtual presence, and can contribute to LPSO in the areas of intelligent and agile surface mobility systems, surface manufacturing and construction systems, and surface environmental management.

SDR Technical Challenges:

• For SDR, the primary challenge is to obtain the fastest possible analog-to-digital (A/D) conversion to directly convert the received RF signal to baseband. Since we intend to use off-the-shelf DSP's, we shall depend to a great extent upon "Moore's Law" (the observed doubling of many technology metrics approximately every 18 months) to yield faster DSP's.

• A related SDR design technical challenge is to manage the large number of samples that result from the direct down-conversion, especially for more complex modulation and encoding schemes. This is typically addressed in SDR design by employing FPGA's or ASIC's for improved throughput.

For Cooperative Robotics, we identify three main technical challenges:

• How is the timing of each node's actions related to each other node (synchronization)?

• How is latency to be handled?

• How can the internal behavior of the network be understood in a way that allows the designer to intelligently make improvements?

Technology Metrics: Acceptance criteria for assessing progress/accomplishment for key milestones

|KEY MILESTONES |Approx. Contract |Abbrev. on Gantt |Technology Metrics |

| |Month |Chart | |

|Phase 1 | | | |

|2-node human / robotic network communicating |6 |2N-10 |Communication bit rate of 10 kbits |

|with software-defined radio. | | |second |

|4-node human / robotic network communicating |12 |4N-50 |Communication bit rate of 50 kbits |

|with software-defined radio. | | |second |

| | | | |

|Demonstrate translation- using an SDR-equipped| | | |

|robot (R2) to bridge a link between two other | |Demo |R1 and R3 enabled to communicate at an |

|colony members (R1 and R3) which have | |Trans |effective bit rate of 10 kbits/sec. |

|different communication protocols from each | | | |

|other. | | | |

|Phase 2 | | | |

|Cycle 2 SDR boards designed |18 |Design-2 |100 kbits/s |

|Three (3) LaRC Mobile robots operational |24 |3MR-50 |Capable of transceiving using SDR at 50 |

| | | |kbits/sec and fully controlled motion |

|4-node human / robotic network communicating |30 |4N-100 |Communication bit rate of 100 kbits |

|with software-defined radio. | | |second |

| | | | |

|Cycle 3 SDR boards designed | | | |

| | |Design-3 |200 kbits w/ advanced modulation and |

| | | |encoding |

|Demonstration of robotic cooperative assembly |36 |Demo Assem |Structure consisting of ten 30 cm long, |

|of a structure with human guidance. Human | | |1 cm diam. alum. rods constructed in 1 |

|selects structure, two robots assemble it, | | |hour. |

|third robot brings parts. | | | |

|Demonstration of a servicing operation in |42 |Demo Service |Operation completed successfully 4 out |

|which a rover on a planet surface (R1) is to | | |of 5 tries. |

|be serviced by a newer, SDR-equipped machine | | | |

|(R2). The scenario requires the two to | | | |

|communicate, and requires some remote human | | | |

|(H) intervention. | | | |

|7-node human / robotic network communicating |48 |7N-200 |Communication bit rate of 200 kbits |

|with software-defined radio. | | |second |

c. A description of the impact of the proposed technology to future exploration systems, including specific benefits to exploration, and overall long-term use (e.g. future systems live Crew Exploration Vehicles, lunar rovers, lunar-planetary bases, etc)

Exploration systems of the future will undoubtedly involve multiple vehicles fanning out over planet surfaces, together with numerous manned and unmanned entities in orbit or in transit between planets. In any conceivable scenario, it will be of the utmost importance for each entity to have the ability to communicate with all or a subset of the others with high reliability. Furthermore, tasks such as exploration, assembly, and inspection will need to be accomplished through cooperation and will require highly flexible "plug and play" communication systems as proposed here. The proposed work provides a demonstrative, prototype infrastructure for sustainable missions of the type described in the Formulation Plan. It also provides for reconfigurability and adaptability to new environments and unforseen circumstances.

7. Statement of Work (SOW)

This section provides a Statement of Work (SOW) segregated by Phase 1 and Phase 2 (yearly). The following sections are included: (7.1) Scope (7.2) Objectives (7.3) SOW tasks organized in a Work Breakdown Structure (WBS), (7.4) Program Schedule & Milestones, (7.5) Acceptance criteria (e.g. key technology metrics) for assessing progress/accomplishment for key milestones, and (7.6) deliverables, which shall are defined and described under the applicable task/WBS portion of the SOW.

7.1 Scope

The scope and aim of the proposed project is to develop a simulated interplanetary exploration environment in which a laboratory-based heterogeneous colony of cooperative robots interact, enabled by software radio. Communication latency will be introduced artificially to mimic time delays consistent with interplanetary missions. Members of the colony will be use a variety of communication modes in order to simulate a realistic scenario useful to NASA in which communicating entities most likely will not be equipped with identical transceivers. The project will begin at technology readiness level (TRL) 2 and end at TRL 4, as defined in the BAA (ref. Fig. 1).

7.2 Objectives

Phase 1 Objectives:

1. Have in place an operational four-node human / robotic network communicating with software-defined radio.

2. Have in place a working demonstration of two simple, NASA-relevant cooperative activities within the colony which could not be achieved effectively without employing SDR: (i) intelligent real-time adjustment of communication parameters to overcome channel degradation, and (ii) translation- using an SDR to bridge a link between two other colony members using different protocols.

3. Have a design for new DSP boards for Phase 2, Year 1 essentially finished.

Phase 2 Objectives:

1. Have in place an operational seven-node human / robotic network communicating with software-defined radio.

2. Have in place a working demonstration of cooperative assembly of a structure under remote (large time delay), minimal human guidance.

3. Have in place a working demonstration of a servicing operation in which a rover on a planet surface is to be serviced by a newer, SDR-equipped machine. The scenario requires the two to communicate, and requires some remote human intervention.

7.3 Work Breakdown Structure (WBS)

The WBS for this project is as follows (identical for Phase 1 and Phase 2):

Level 1 – Project

Level 2: Work Products A – E

A. Software-defined radio (SDR)

B. Cooperative telerobotics software environment (CTSE)

C. Human and robotic physical nodes (HRN)

D. System monitoring software environment (SMSE)

E. Project management, project reports and documentation (PRD)

The Level 2 Work Products A – E are described in detail in the following subsections.

7.3.1 Work Product A: Software-defined radio (SDR)

The software-defined radio work product will consist of a printed wiring board (PWB) containing a digital signal processor (exact model to be determined as part of investigation), several RF components, e.g., bandpass filter, power amplifier, as determined in the design effort, and baseband electronics such as buffer amplifier(s) and power management. The design will be a collaboration between Auburn University (Dr. Roppel, Dr. Jaeger) and commercial partner CoachComm (Mr. Turkington), with some input from LaRC (Mr. Arthur Bradley at LaRC has considerable RF design experience).

Task A, Phase 1

The initial design for Phase 1 will target a throughput of 10 kbits/s with a conventional modulation scheme such as quadrature phase-shift keying (QPSK). This will provide for a rapid turnaround to permit the Phase 1 milestones and demonstrations to be achieved, and to demonstrate proof of concept.

Task A, Phase 2

The Phase 2 effort in this area will principally be to periodically redesign the SDR to take advantage of expected increasing throughput off-the-shelf DSP's. Redesigns will be initiated at approximately 18 months and 30 months into the overall contract period (6 months and 18 months into Phase 2). This re-design will have two thrusts: operation at higher RF frequencies and higher bit rates, and increased mode complexity. The exact RF modes to be considered will be determined as part of the investigation, but may include direct-sequence or frequency-hopping spread spectrum (DSSS, FHSS) among many other possibilities.

An additional paper study will develop a roadmap for applications beyond the 4-year term of the proposal based on further anticipated improvements in COTS DSP hardware.

7.3.2 Work Product B: Cooperative telerobotics software environment (CTSE)

This will be primarily the responsibility of team member Vanderbilt University Center for Intelligent Systems (Kaz Kawamura, Mitch Wilkes). Auburn University will contribute by helping to integrate the software into the robot and human nodes.

Task B, Phase 1

During Phase 1, we will implement a software module that can reside on each node (human or robot) to enable cooperative behavior. This is intended to be general in nature to enable the implementation of a wide variety of interesting scenarios. Example scenario: Human operator desires to teleoperate Robot 1, but communication hardware is incompatible. Robot 2 is equipped with SDR that can "translate" by alternating between the human node's communication mode and Robot 1's communication mode in real time under software control. There are time delays TD1 from human to Robot 1 and TD2 between Robot 1 and Robot 2.

Using existing code as much as possible, we will implement software modules to facilitate cooperative behavior and support high level human commands. Modules will reside on each node, both human or robot centered nodes. Where appropriate these modules will support human robot interaction through graphical user interfaces. Initially the modules will support teleoperation of the robot by a remote human user. In Phase 2 this capability will be expanded.

Task B, Phase 2

We will develop a software environment with sufficient flexibility to allow a variety of cooperation scenarios to be investigated. These may include "virtual presence" applications, collaborative assembly of structures, and coordinated sensing with heterogeneous robot sensor platforms, among others. Additionally, as mentioned in the Phase 1 description, we will add some ability for the robot to act with limited autonomy, yet remain under the supervision of a remote human user. This mode, often called teleassistance, is very practical in the presence of large communication delays. Such delays can make direct teleoperation very difficult and frustrating for the user. Giving the robot limited autonomy to perform basic simple tasks enables the user to direct the actions of the robot in terms of these simple tasks. This type of problem decomposition is more robust in the presence of communication delays.

Hardware needs for phase 2: Virtual reality (VR) or heads-up display, force feedback actuators, cameras, thermal imaging cameras, powerful computing nodes.

We will develop a software environment with sufficient flexibility to allow a variety of cooperation scenarios to be investigated. These may include "virtual presence" applications, collaborative assembly of structures, and coordinated sensing with heterogeneous robot sensor platforms, among others. Additionally, as mentioned in the Phase 1 description, we will add some ability for the robot to act with limited autonomy, yet remain under the supervision of a remote human user. This mode, often called teleassistance, is very practical in the presence of large communication delays. Such delays can make direct teleoperation very difficult and frustrating for the user. Giving the robot limited autonomy to perform basic simple tasks enables the user to direct the actions of the robot in terms of these simple tasks. This type of problem decomposition is more robust in the presence of communication delays.

Hardware needs for phase 2: Virtual reality (VR) or heads-up display, force feedback actuators, cameras, thermal imaging cameras, powerful computing nodes.

7.3.3 Work Product C: Human and robotic physical nodes (HRN)

The construction of the physical network nodes (colony member hardware) will be primarily performed at Auburn University in Phase 1, but represents a significant part of the effort by LaRC during Phase 2.

Task C, Phase 1

Auburn University and LaRC will construct three stationary robot nodes and one human-interface node each designed to interface with the SDR designed in Task A. The stationary robot nodes will have, at a minimum, one gripper arm, a color video /still digital camera on a rotating mount, and an ultrasonic range / presence sensor. The human-interface node will be a computer workstation capable of running the software developed in Tasks B and D. This workstation will also be modified and equipped as required to interface to the SDR developed in Task A.

During Phase 1, LaRC will also design the mobile robots to be constructed in Phase 2.

Task C, Phase 2

During the first year of Phase 2, team member LaRC (Robotics and Intelligent Machines Laboratory - Dr. Arthur Bradley) will build three mobile robots to be used as subsequent mobile network nodes equipped with SDR from Task A. During years 2 and 3, these robots will be refined and outfitted with various sensors and actuators, which may include infrared cameras, tactile feedback, and magnetometers among many other possibilities. The design details will depend largely on results of ongoing investigation.

During Phase 2, Auburn University will focus on improving the stationary robot nodes constructed in Phase 1, with the goal of making them as agile and responsive as possible.

7.3.4 Work Product D: System monitoring software environment (SMSE)

Task D, Phase 1

Task D, Phase 2

7.3.5 Project management, project reports and documentation (PRD)

Task E, Phase 1

Task E, Phase 2

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