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HUMAN MACHINE COOPERATIVE TELEROBOTICS
The remediation and deactivation and decommissioning (D&D) of nuclear waste storage tanks using telerobotics is one of the most challenging tasks faced in environmental cleanup. Since a number of tanks have reached the end of their design life and some of them have leaks, the unstructured, uncertain and radioactive environment makes the work inefficient and expensive. However, the execution time of teleoperation consumes ten to hundred times that of direct contact with an associated loss in quality. Thus, a considerable effort has been expended to improve the quality and efficiency of telerobotics by incorporating into teleoperation and robotic control functions such as planning, trajectory generation, vision, and 3-D modeling. One example is the Robot Task Space Analyzer (RTSA), which has been developed at the Robotics and Electromechanical Systems Laboratory (REMSL) at the University of Tennessee in support of the D&D robotic work at the Oak Ridge National Laboratory and the National Energy Technology Laboratory. This system builds 3-D models of the area of interest in task space through automatic image processing and/or human interactive manual modeling. The RTSA generates a task plan file, which describes the execution of a task including manipulator and tooling motions. The high level controller of the manipulator interprets the task plan file and executes the task automatically. Thus, if the environment is not highly unstructured, a tooling task, which interacts with environment, will be executed in the autonomous mode. Therefore, the RTSA not only increases the system efficiency, but also improves the system reliability because the operator will act as backstop for safe operation after the 3-D models and task plan files are generated. However, unstructured conditions of environment and tasks necessitate that the telerobot operates in the teleoperation mode for successful execution of task. The inefficiency in the teleoperation mode led to the research described as Human Machine Cooperative Telerobotics (HMCTR). The HMCTR combines the telerobot with robotic control techniques to improve the system efficiency and reliability in teleoperation mode. In this topical report, the control strategy, configuration and experimental results of Human Machines Cooperative Telerobotics (HMCTR), which modifies and limits the commands of human operator to follow the predefined constraints in the teleoperation mode, is described. The current implementation is a laboratory-scale system that will be incorporated into an engineering-scale system at the Oak Ridge National Laboratory in the future
Evidence for the Decay
We present a search for the ``wrong-sign'' decay D0 -> K+ pi- pi+ pi- using 9
fb-1 of e+e- collisions on and just below the Upsilon(4S) resonance. This decay
can occur either through a doubly Cabibbo-suppressed process or through mixing
to a D0bar followed by a Cabibbo-favored process. Our result for the
time-integrated wrong-sign rate relative to the decay D0 -> K- pi+ pi- pi+ is
(0.0041 +0.0012-0.0011(stat.) +-0.0004(syst.))x(1.07 +-0.10)(phase space),
which has a statistical significance of 3.9 standard deviations.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Hadronic Mass Moments in Inclusive Semileptonic B Meson Decays
We have measured the first and second moments of the hadronic mass-squared
distribution in B -> X_c l nu, for P(lepton) > 1.5 GeV/c. We find <M_X^2 -
M_D[Bar]^2> = 0.251 +- 0.066 GeV^2, )^2 > = 0.576 +- 0.170
GeV^4, where M_D[Bar] is the spin-averaged D meson mass.
From that first moment and the first moment of the photon energy spectrum in
b -> s gamma, we find the HQET parameter lambda_1 (MS[Bar], to order 1/M^3 and
beta_0 alpha_s^2) to be -0.24 +- 0.11 GeV^2. Using these first moments and the
B semileptonic width, and assuming parton-hadron duality, we obtain |V_cb| =
0.0404 +- 0.0013.Comment: 11 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Observation of the Charmed Baryon at CLEO
The CLEO experiment at the CESR collider has used 13.7 fb of data to
search for the production of the (css-ground state) in
collisions at {\rm GeV}. The modes used to
study the are ,
, , , and
. We observe a signal of 40.49.0(stat) events
at a mass of 2694.62.6(stat)1.9(syst) {\rm MeV/}, for all modes
combined.Comment: 10 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Observation of and
We have studied two-body charmless hadronic decays of mesons into the
final states phi K and phi K^*. Using 9.7 million pairs collected
with the CLEO II detector, we observe the decays B- -> phi K- and B0 -> phi K*0
with the following branching fractions: BR(B- -> phi K-)=(5.5 +2.1-1.8 +- 0.6)
x 10^{-6} and BR(B0 -> phi K*0)=(11.5 +4.5-3.7 +1.8-1.7) x 10^{-6}. We also see
evidence for the decays B0 -> phi K0 and B- -> phi K*-. However, since the
statistical significance is not overwhelming for these modes we determine upper
limits of <12.3 x 10^{-6} and <22.5 x 10^{-6} (90% C.L.) respectively.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
First Observation of B -> D(*) rho', rho' -> omega pi-
We report on the observation of B-> D(*) pi+ pi- pi- pi^o decays. The
branching ratios for D*+ and D*o are (1.72+/-0.14+/-0.24)% and
(1.80+/-0.24+/-0.27)%, respectively. Each final state has a D* omega pi-
component, with branching ratios (0.29+/-0.03+/-0.04)% and
(0.45+/-0.10+/-0.07)% for the D*+ and D*o modes, respectively. We also observe
B -> D omega pi- decays. The branching ratios for D+ and Do are
(0.28+/-0.05+/-0.04)% and (0.41+/-0.07+/-0.06)%, respectively. A spin parity
analysis of the D omega pi- final state prefers a wide 1^- resonance. A fit to
the omega pi- mass spectrum finds a central mass of (1349+/-25^{+10}_{-5}) MeV
and width of (547+/-86^{+46}_{-45}) MeV. We identify this object as the
rho(1450) or the \rho'.Comment: 42 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, To Appear in PR
Search for the Decay
We report on a search for the radiative decay U(1S) -> gamma + eta' in 61.3
pb^-1 of data taken with the CLEO II detector at the Cornell Electron Storage
Ring. Three decay chains were investigated, all involving eta' -> pi+ pi- +
eta, followed by eta -> gamma + gamma, eta -> pi0 + pi0 + pi0, or eta -> pi+ +
pi- + pi0. We find no candidate events in any of the three cases and set a
combined upper limit of 1.6 x 10^-5 at 90% C.L., significantly smaller than the
previous limit. We compare our result to other radiative U(1S) decays, to
radiative J/psi decays, and to theoretical predictions.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Evidence of New States Decaying into
Using 13.7 of data recorded by the CLEO detector at CESR, we report
evidence for two new charmed baryons: one decaying into
with the subsequent decay , and its
isospin partner decaying into followed by
. We measure the following mass differences
for the two states: =318.2+-1.3+-2.9 MeV,
and =324.0+-1.3+-3.0 MeV. We interpret
these new states as the particles, the charmed-strange
analogs of the .Comment: 10 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Measurement of the Relative Branching Fraction of to Charged and Neutral B-Meson Pairs
We analyze 9.7 x 10^6 B\bar{B}$ pairs recorded with the CLEO detector to
determine the production ratio of charged to neutral B-meson pairs produced at
the Y(4S) resonance. We measure the rates for B^0 -> J/psi K^{(*)0} and B^+ ->
J/psi K^{(*)+} decays and use the world-average B-meson lifetime ratio to
extract the relative widths f+-/f00 = Gamma(Y(4S) -> B+B-)/Gamma(Y(4S) ->
B0\bar{B0}) = = 1.04 +/- 0.07(stat) +/- 0.04(syst). With the assumption that
f+- + f00 = 1, we obtain f00 = 0.49 +/- 0.02(stat) +/- 0.01(syst) and f+- =
0.51 +/- 0.02(stat) +/- 0.01(syst). This production ratio and its uncertainty
apply to all exclusive B-meson branching fractions measured at the Y(4S)
resonance.Comment: 11 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
First Observation of the Decays and B^{0}\to D^{*-}p\bar{n}$
We report the first observation of exclusive decays of the type B to D^* N
anti-N X, where N is a nucleon. Using a sample of 9.7 times 10^{6} B-Bbar pairs
collected with the CLEO detector operating at the Cornell Electron Storage
Ring, we measure the branching fractions B(B^0 \to D^{*-} proton antiproton
\pi^+) = ({6.5}^{+1.3}_{-1.2} +- 1.0) \times 10^{-4} and B(B^0 \to D^{*-}
proton antineutron) = ({14.5}^{+3.4}_{-3.0} +- 2.7) times 10^{-4}. Antineutrons
are identified by their annihilation in the CsI electromagnetic calorimeter.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
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