THanks for your inputs...
Blake
At 01:59 AM 12/2/98 -0800, Tom Anderson wrote:
>Stefan and David -- Blake is writing a proposal to DARPA
>to fund a vertically integrated demonstration of haptic
>(force feedback) interfaces, for the software
>control BAA (08). There are technical issues with respect
>to software control, but the part he'd like help with is
>the real time interactive UI over the net.
>
>Here's my take on the research issues, please add your views.
>I'm no expert in QoS, but one of our target apps for Detour
>is latency-sensitive games, and that's up Blake's alley.
>
>1. with dedicated links and programmable routers, easy to
>provide strict real time guarantees (in a previous life I published
>some work a while back that you can do guarantees given static
>schedules and loosely synchronized clocks at the routers).
>
>2. internet today is hit and miss. If you're running over a wildly
>underutilized link such as Internet2, easy. If you're running on
>one of our prototypical lossy Internet links, no chance -- there's
>too big a tail to latencies and drops.
>
>3. it's not clear to me that the current approach that the Internet
>router vendors will work. Is it enough in general to have priorities
>for switch scheduling and buffer allocation? The ATM experience said no.
>But I don't know if this has been proven one way or the other.
>It would be great to be able to claim that the industry approach won't work.
>
>4. One problem with priorities is that it confounds two issues --
>how important something is with what kind of service it needs.
>In general, I suspect it's like the old results about CPU scheduling --
>you improve average performance by doing short jobs first. The short
>jobs are simple web surfing; the long jobs are the real time ones.
>There's been some interesting work in various places that look at
>deferring real time work, to allow best effort to go first as long
>as it doesn't interfere with meeting deadlines.
>
>5. on a virtual network (layered on top of the physical Internet)
>things become interesting
>
> -- we can monitor performance of individual routes, and change
> FEC to compensate for drop rates and delay variations.
> this is equivalent to the issue where you have a wireless
> device switch zones (e.g., by entering a building), thereby
> getting better or worse performance
>
> -- we can change the virtual route to avoid dynamic problem areas
> (presumably reducing the tail, provided the variability in the
> network occurs more slowly than the control loop -- eg., 1 RTT)
>
> -- we can adapt at the application level. If the network reports
> that the performance it can provide has changed, then the app
> can potentially compensate by making the control stiffer (I'm
> making this up, but it sounds plausible).
>
> -- we can reduce loss rates and queuing variations by shaping
> and/or rerouting other traffic (e.g., traffic produced by a Detour
> congestion gateway will cause less variation in performance for
> other traffic because its impact will be smoother)
>
>tom
>------
>X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.5 (32)
>Date: Tue, 01 Dec 1998 10:05:27 -0800
>To: wmcneely@espresso.rt.cs.boeing.com, pbuttolo@ford.com,
> steve@isdl.ee.washington.edu, rjadams@u.washington.edu,
> tom@cs.washington.edu, moreyra@cris.com
>From: Blake Hannaford <blake2@rcs.ee.washington.edu>
>Subject: DARPA Pre-Pro Draft
>Mime-Version: 1.0
>Content-Type: text/plain; charset="us-ascii"
>Status: RO
>
>Please give me any comments you have on this next-to-final
>draft by end of day Wed.
>
>Thanks!
>
>Blake
>
> High Performance Networked-Control for Shared Haptic Interaction
> and Telerobot Control
>
> White Paper for DARPA BAA #99-08
>
> University of Washington
> Boeing Company
> Ford Motor Company
> Air Force Institute of Technology
>
>
> Prof. Blake Hannaford
> Department of Electrical Engineering
> University of Washington
> Seattle, WA 98195-2500
> http://rcs.ee.washington.edu/BRL
> 1-206-543-2197(voice)
> 1-206-543-3842(fax)
>
>1. Objective
>
>This project proposes to create an internet-based distributed control
>system for haptic interaction and telerobotic control. Haptic
>interaction allows users to touch and physically interact with computer
>models or remote objects. The proposed system will seamlessly interface
>a variety of commercial and research haptic devices, telerobots, and
>advanced CAD-based real-time simulations, into a distributed network
>based on existing and newly created public standard prototcols.
>
>
>2. Team
>
>University of Washington.
> Prof. Blake Hannaford, (PI)
> Prof. Tom Anderson (Co-I)
>
>Air Force Institute of Technology
> Prof. Richard Adams (Co-I)
> (position begins Sept 99)
>
>Boeing Information Support Services
> Dr. William McNeely
> Dr. James Troy
> Dr. Steven Venema (full time at Boeing 2/1/99)
>
>Ford Corporate Research Labs
> Dr. Pietro Buttolo
> Dr. Paul Stewart
>
>Haptic Technologies Inc (Seattle)
> Manuel Moreyra, President
>
>This team has worked together for the past several years on various
>small projects funded primarily by the industry group. Together, we are
>seeking a combination of resources necessary to create a shared vision
>of better design and remote control capabilities through advanced
>software enabled networked control systems.
>
>The proposed vision cannot be realized without significant advances in
>the state of the art of control, distributed software, networking, and
>human-computer-interaction. We believe that the time is ripe for
>a breakthrough in these areas through leveraging of commodity computing
>power and open software protocols. We propose to coordinate our efforts
>by focusing on the realization of a proptotype advanced networked CAD
>system.
>
>3. Technical Innovations
>
>Our project would aim to create the following technical
>innovations:
>
>Open protocols for interconnection of haptic devices, real-time
>dynamic simulations, and robots.
>
>[Networking Innovations ... ANDERSON]
>
>Stable and high performance distributed controllers for bi-directional
>interaction between humans, dynamic virtual worlds, and telerobots
>mediated by advanced haptic devices.
>
>Advanced manipulator control laws which leverage minimal cost computing
>power to intelligently and robustly control slave robots and haptic
>devices in the region of kinematic singularities.
>
>4. Testbed Implementation
>
>The team would implement a testbed system over the internet supporting
>seamless interaction between the following elements:
>
>Advanced human operator control station (UW)
>
>Telerobot Cell (UW)
>
>Advanced Networking testbed (UW)
>
>Realtime Airframe CAD model (Boeing)
>
>Realtime Car interior CAD model (Ford)
>
>CAVE Virtual Environment and Robot testbed (AFIT)
>
>The advanced networking testbed would allow us to test new network
>routing strategies which we cannot yet implement in the real
>internet.
>
>5. Technical Rationale
>
>Haptic interaction is a key centerpiece of emerging human-centered
>computing and control. Human reaction time to haptic stimuli (about
>150ms) is about half of that of visual stimuli (about 300ms). Haptic
>interaction provides better and more intutive human control of both
>virtual worlds, and remote physical worlds (via telerobots). Intense
>industrial interest is emerging in haptic technolgies for evalution of
>designs and CAD models. The benefits of haptic human-computer-
>interaction are expected to be even grater in distributed networked
>interactions in which, for example, designers around the world
>collaborated on a haptically and visually rendered CAD model. However
>key technical barriers remain. Chief among these is stable and high
>performance haptic control in a network characterized by stochasitcally
>varying time delay.
>
>The proposed project will develop low level software, network protocols,
>and device control laws to break down this barrier and enable these new
>applications. We will create a working prototype network in which a user
>at each of the team locations will be able to physically interact with
>models at all of the locations. Two of the locations (UW and AFIT) will
>also have telerobots to which any user can connect.
>
>All the sites will have advanced 6 degree of freedom haptic display
>devices. Specific results expected from the project are:
>
>5.1 New Control Capability: Stable, high performance bi-lateral control
>over local and wide-area networks with large scale detailed CAD models.
>
>5.2 Open Control Environment: Testbed implementation will be
>demonstrated over internet. Socket level connection protocol will be
>defined and made public.
>
>5.3 Evaluation and Experimentation Strategies:
> 5.3.1 Collect Internet packet latency stats.
> 5.3.2 Test interaction between operator stations at all
>locations with all "servers" (i.e. robots and models). Rate all
>interactions in terms of stability and perceptual quality.
> 5.3.3 Formally evaluate
> o stability/gain trade-offs.
> o Human operator surface feature descrimination ability.
> o Completion time of an assembly and maintenance task.
>
>
>------------------------------------------------------------------------
>Prof. Blake Hannaford, Dept. of Electrical Engineering
>University of Washington, Seattle, Wa USA 98195-2500.
>Ph: 1-206-543-2197 Fax: 1-206-543-3842
>Faculty Openings: http://www.ee.washington.edu/jobs/chronfac.html
>------------------------------------------------------------------------
>
>
>
------------------------------------------------------------------------
Prof. Blake Hannaford, Dept. of Electrical Engineering
University of Washington, Seattle, Wa USA 98195-2500.
Ph: 1-206-543-2197 Fax: 1-206-543-3842
Faculty Openings: http://www.ee.washington.edu/jobs/chronfac.html
------------------------------------------------------------------------