US5086400A — Bilevel shared control for teleoperators

Claim 1

Independent Claim 247 words

A hierarchical robotic control system for controlling a robot located at a remote site which is remotely located from a point of command over said robot at a local site, which robotic control system experiences communication time delays between said local and remote sites and shares autonomous and teleoperator hand-controller ("teleoperator") commands including motion and force, a task trajectory for performing a given task, and a teleoperator trajectory as directed by a teleoperator for remotely performing said given task, all expressed as individual command signals applied to and fed back from said control system, with said commands being implemented in said control system in a task level and in an execution level, said robotic control system comprising: a task level including means for controlling said robot in motion and force, task trajectories, and/or teleoperator trajectories in said task level to control tasks being performed by said robot; an execution level including means at said local site for transforming teleoperator command signals which are subjected to said communication time delays from a local coordinate system at said local site to the coordinates being used as task level commands at said robot's remote site; and a combined command signal selection and signal mixing means at the remote site for varying the effectiveness in autonomous control over said robot by said communication time delayed teleoperator command signals in accordance with the length of communication time delays said teleoperator command signals experience in travelling between said local and said remote sites.

Claim 2

Dependent Claim 247 words

A hierarchical robotic control system for controlling a robot located at a remote site which is remotely located from a point of command over said robot at a local site, which robotic control system experiences communication time delays between said local and remote sites and shares autonomous and teleoperator hand-controller ("teleoperator") commands including motion and force, a task trajectory for performing a given task, and a teleoperator trajectory as directed by a teleoperator for remotely performing said given task, all expressed as individual command signals applied to and fed back from said control system, with said commands being implemented in said control system in a task level and in an execution level, said robotic control system comprising: a task level including means for controlling said robot in motion and force, task trajectories, and/or teleoperator trajectories in said task level to control tasks being performed by said robot; an execution level including means at said local site for transforming teleoperator command signals which are subjected to said communication time delays from a local coordinate system at said local site to the coordinates being used as task level commands at said robot's remote site; and a combined command signal selection and signal mixing means at the remote site for varying the effectiveness in autonomous control over said robot by said communication time delayed teleoperator command signals in accordance with the length of communication time delays said teleoperator command signals experience in travelling between said local and said remote sites.

Claim 3

Dependent Claim 87 words

A control system in accordance with claim 1 wherein the time delays introduce detrimental effects into said robotic control system and sharing of control by said combined signal selection and mixing means minimizes detrimental effects, and wherein said system's signal selection and mixing means further comprises: weighted signal mixing means at the task level, should the communication time delay between said local and remote sites be significant, allowing weighted mixing of teleoperator commands with said autonomous command only along motion directions, while forces are controlled only autonomously.

Claim 4

Dependent Claim 82 words

A control system in accordance with claim 1 wherein said robotic control system commands actual robot motion/force via a modified signal command as modified either from a local and/or a remote site, and said system's weighted signal mixing means further comprises: signal mixing matrices at the task level for deciding when, what and how much of the teleoperator command signals from said remote and/or said local site are to be effective in forming combined modified commands for actual control over said robot.

Claim 5

Dependent Claim 65 words

A control system in accordance with claim 3 wherein said sharing of control minimizes the detrimental effects caused by the communication time delays, and wherein said combined signal selection and mixing matrices further comprises: a signal selection matrix for selecting which of said autonomous and/or said teleoperator command signals will be effective in contributing to said modified signal commands for actual control over said robot.

Claim 6

Dependent Claim 66 words

A control system in accordance with claim 3 wherein said sharing of control minimizes the detrimental effects caused by the communication time delays, and wherein said signal mixing matrices further comprises: signal weighting matrices for determining how much of any command signal(s) actually reaches the robot and what share of such signals will contribute to said modified command signal(s) that have actual control over said robot.

Claim 7

Dependent Claim 170 words

A hierarchal robot control system for a robot in which teleoperator and/or autonomous commands trade and share control over a robot and said commanded control is distributed over a remote site and a local site, with task-level and servo-control occurring solely at said remote site to actually drive said robot in motion/force at said remote site, said robot control system comprising: an autonomous planner; means responsive to said autonomous planner for developing a series of task-level execution commands; a task-level sharing means located at the remote site for receiving commands from said autonomous planner; a source of teleoperator commands; means for transmitting teleoperator commands to the sharing means for mixing the teleoperator commands with autonomous commands for application to said robot control system; a separation means separate and distinct from said sharing means; and means for feeding back to said teleoperator at the remote/local site information about actual robot motions, end-effector contact and inertial forces taking place at said remote site from a shared combination of teleoperator and autonomous commands.

Claim 8

Dependent Claim 170 words

A hierarchal robot control system for a robot in which teleoperator and/or autonomous commands trade and share control over a robot and said commanded control is distributed over a remote site and a local site, with task-level and servo-control occurring solely at said remote site to actually drive said robot in motion/force at said remote site, said robot control system comprising: an autonomous planner; means responsive to said autonomous planner for developing a series of task-level execution commands; a task-level sharing means located at the remote site for receiving commands from said autonomous planner; a source of teleoperator commands; means for transmitting teleoperator commands to the sharing means for mixing the teleoperator commands with autonomous commands for application to said robot control system; a separation means separate and distinct from said sharing means; and means for feeding back to said teleoperator at the remote/local site information about actual robot motions, end-effector contact and inertial forces taking place at said remote site from a shared combination of teleoperator and autonomous commands.

Claim 9

Dependent Claim 65 words

A hierarchal control system for robot control in accordance with claim 6 in which control is distributed over a remote site and a local site, and further comprising: means available to a teleoperator at said local site for generating teleoperative inputs as deemed necessary by said planner at said remote site for performing mixed correction commands for control over said robot at said remote site.

Claim 10

Independent Claim 165 words

A method of shared control over a robot separated from an autonomous command location by varying amounts of communication time delays for teleoperator command signals employed in said shared control, said method compensating for differences in communication time delays by the method steps of: dividing control architecture for controlling said robot into a task level and an execution level; supplying command input signals in a task coordinate system as a task coordinate input command, a task trajectory input command, and a teleoperator trajectory input command; employing a hybrid position/force task representation for low-level tasks, whereby the task coordinate system consists of orthogonal motion and force coordinates, a task trajectory and teleoperator trajectories of appropriate motion and force; and compensating for said communication time delays by altering the teleoperator trajectory in accordance with the length of time delays actually encountered for said teleoperator commands so that the robot is controlled free of inaccuracies which tend to be introduced into control because of said communication time delays.

Claim 11

Independent Claim 165 words

A method of shared control over a robot separated from an autonomous command location by varying amounts of communication time delays for teleoperator command signals employed in said shared control, said method compensating for differences in communication time delays by the method steps of: dividing control architecture for controlling said robot into a task level and an execution level; supplying command input signals in a task coordinate system as a task coordinate input command, a task trajectory input command, and a teleoperator trajectory input command; employing a hybrid position/force task representation for low-level tasks, whereby the task coordinate system consists of orthogonal motion and force coordinates, a task trajectory and teleoperator trajectories of appropriate motion and force; and compensating for said communication time delays by altering the teleoperator trajectory in accordance with the length of time delays actually encountered for said teleoperator commands so that the robot is controlled free of inaccuracies which tend to be introduced into control because of said communication time delays.

Claim 12

Dependent Claim 46 words

A method of control in accordance with claim 8 and further comprising in said compensating step the additional method step of: removing from said teleoperator, based upon the amount of communication time delays, any reflectance force so that motion control alone is available to the teleoperator.

Claim 13

Dependent Claim 64 words

A method of control in accordance with claim 8 wherein the control architecture is located in outer space and the teleoperator is earth based, and wherein the method includes the further steps of: measuring the communication time delays between the local and the remote locations; and said compensating step further includes sharing control over said robot by a mixture of autonomous and teleoperator controls.

Claim 14

Dependent Claim 51 words

A method of control in accordance with claim 10, should the communication delays exceed a predetermined minimum, which includes the further method step of: mixing teleoperator and autonomous control at the task level only along motion directions, while mixing does not occur in force, so that forces are controlled only autonomously.

Claim 15

Dependent Claim 62 words

A method of control in accordance with claim 11 and comprising additional sub-steps of dividing the mixing step so that it consists of: deciding what signals are to be mixed, when such signals may mix, and how effective in robot control the mixed signals will be; and making the decision in accordance with mixing matrix entries which reflect each signal input's modality.

Claim 16

Dependent Claim 36 words

A method of control in accordance with claim 12 and further comprising the step of: rendering the control architecture to be oblivious to the nature of the signals causing an actual trajectory at said execution level.

Claim 17

Independent Claim 130 words

A method of control over a robot for guiding the robot's actual trajectory/force wherein the robot is remotely located from a command location which issues an autonomous command and said robot is also subject to control by a teleoperator, said method comprising the steps of: remotely selecting an effective command for control over said robot directly from said autonomous command; remotely selecting an effective command directly from said teleoperator; placing entries in a mixing matrix that receives the selected commands in order to remotely select an effective command directly from a mixture of the selected commands without either the autonomous or the teleoperator being aware of their contribution to the total command that controls the robot; and mixing the selected commands in accordance with the entries in the mixing matrix.

Claim 18

Independent Claim 130 words

A method of control over a robot for guiding the robot's actual trajectory/force wherein the robot is remotely located from a command location which issues an autonomous command and said robot is also subject to control by a teleoperator, said method comprising the steps of: remotely selecting an effective command for control over said robot directly from said autonomous command; remotely selecting an effective command directly from said teleoperator; placing entries in a mixing matrix that receives the selected commands in order to remotely select an effective command directly from a mixture of the selected commands without either the autonomous or the teleoperator being aware of their contribution to the total command that controls the robot; and mixing the selected commands in accordance with the entries in the mixing matrix.

Claim 19

Dependent Claim 27 words

A method of control in accordance with claim 14 and further comprising the step of: sharing actual robot control by mixing the teleoperator and autonomous input modalities.

Claim 20

Dependent Claim 68 words

A method of control in accordance with claim 15 wherein the robot exhibits a nominal autonomous and a nominal teleoperator behavior, and said method further comprises the step of sharing control by: (1) either the nominal autonomous behavior may be modified by a teleoperator, or (2) the nominal teleoperator behavior may be modified autonomously, and (3) accomplishing approaches (1) and (2) by doing the modifying in selection/mixing matrices.

Claim 21

Dependent Claim 55 words

A method of control in accordance with claim 16 and further comprising the steps of: modifying nominal autonomously planned motion trajectories by a teleoperator in order to track unmodelled target motions in the autonomously planned motion; and modifying nominal teleoperator motions through compliance to accommodate geometric errors autonomously in motions being controlled by the teleoperator.

Claim 22

Dependent Claim 86 words

A method of control in accordance with claim 17 wherein the robot being controlled is located in outer space and the teleoperator is earth based such that communication between the teleoperator and the robot experiences communication time delays that introduce detrimental effects in control over the robot, and wherein the method includes the further steps of: sharing control in accordance with the length of the communication time delays in order to minimize the detrimental effects caused by the communication time delays between outer space and earth.

Claim 23

Dependent Claim 45 words

A method of control in accordance with claim 18, should the communication time delay exceed a predetermined minimum, which includes the further step of: allowing mixing of teleoperator and autonomous control at the task level only along motion directions, while forces are controlled only autonomously.

Claim 24

Independent Claim 114 words

A method of control over a robot which may operate in one of three modes, i.e. moving freely, or just about to establish contact, or else, may have already established stable contact, wherein a robot and a command station are in an environment that introduces time delay between command and actual controlled movement in motion/force at said robot, the method comprising: operating control over said robot by a shared system; autonomously providing nominal task trajectories; allowing said nominal task trajectories to be modified by the teleoperator only in those directions where contact is not established; and performing force control autonomously while the teleoperator is affecting the nominal task trajectories in the absence of contact.

Claim 25

Independent Claim 114 words

A method of control over a robot which may operate in one of three modes, i.e. moving freely, or just about to establish contact, or else, may have already established stable contact, wherein a robot and a command station are in an environment that introduces time delay between command and actual controlled movement in motion/force at said robot, the method comprising: operating control over said robot by a shared system; autonomously providing nominal task trajectories; allowing said nominal task trajectories to be modified by the teleoperator only in those directions where contact is not established; and performing force control autonomously while the teleoperator is affecting the nominal task trajectories in the absence of contact.

Claim 26

Dependent Claim 173 words

A hierarchical robotic control system operating in accordance with the method of claim 20 for controlling a robot located at a site which is remote from the point of command at a local site, which system shares autonomous and hand-controller ("teleoperator") commands that are implemented in a task level and in an execution level, said control method further characterized by the steps of: establishing a task level for controlling said robot in response to orthogonal motion and force coordinates, task trajectories, and a teleoperator trajectory; expressing command signals in said task level to control tasks being performed by said robot; establishing an execution level at a local site which is remote from said robot's location; transforming teleoperator signals from a local coordinate system at said local site to the coordinates being used as commands in said task level at said robot's remote site; and weighting the effectiveness in control over said robot by said teleoperator signals in accordance with the length of the communication time delays between said local and said remote sites.

Claim 27

Dependent Claim 65 words

A method of control in accordance with claim 21 wherein said control system includes detrimental effects caused by communication time delays, and sharing of control minimizes such detrimental effects, and wherein said method further comprises the steps of: allowing, should the communication time delay between said local and remote sites be significant, integration of teleoperator commands only along motion directions, while controlling forces only autonomously.

Claim 28

Dependent Claim 96 words

A control system and method of control in accordance with claim 22 wherein said method further comprises: forming modified command signals for controlling said robot by said modified command signals only; deciding by signal mixing matrices at the task level when, what and how much of the command signals from the remote and the local sites are to be effective in the formation of said modified commands; and passing the command signals through mixing matrices, in order to formulate said modified commands for control of said robot as a modified signal output from said mixing matrices.

Claim 29

Dependent Claim 82 words

A control system and method of control in accordance with claim 23 wherein said method further comprises: the communication time delays in transmission causes the robot to deviate away from its desired path; such communication time delay in a return transmission path causes the feedback information to be obsolete resulting in errors in the specification of a desired path for the robot to follow; and compensating for instabilities in the control system which results from both transmission delay and obsolete feedback information.

Claim 30

Dependent Claim 76 words

A control system and method of control for motion and force of a contact type by a robot in accordance with claim 24 wherein said method further comprises: sharing signal control over said robot, at the task level, as follows; let the robot's motions and forces allowable by the contact type to be represented by 6×1 vectors M and F; let M(i) represent the i th row of M, then: M(i)=1, if motion freedom exists,=0 otherwise.

Claim 31

Dependent Claim 34 words

A control system and method of control in accordance with claim 25 wherein said method further comprises: similarly, F(i) is 0 or 1 depending on whether force freedom in that direction exists or not.

Claim 32

Dependent Claim 28 words

A control system and method of control in accordance with claim 26 wherein said method further comprises: a standard for a hybrid task representation expressed as: F.sup.T M=0.

Claim 33

Dependent Claim 55 words

A control system and method of control in a task coordinate system in accordance with claim 26 wherein said method further comprises: also, let .sup.α M and .sup.α F represent desired motion and force trajectories, said method being further characterized in that; said task coordinate system is represented by ##EQU21## and the corresponding Jacobian, ##EQU22##

Claim 34

Dependent Claim 52 words

A control system and method of control in accordance with claim 26 and further comprising: implementation of said method by a feedforward loop for feeding command information to said robot to be controlled and a feedback loop for feeding back response information about the robot's actual movements as sensed at said robot.

Claim 35

Dependent Claim 54 words

A control system and method of control in accordance with claim 29 and further comprising: input and output signals in said feedforward loop, with said input and output signals being at the task level, and consisting of the following components: ##EQU23## where←indicates what information is contained in a feedforward command in said feedforward loop.

Claim 36

Dependent Claim 68 words

A control system and method of control in accordance with claim 30 and wherein said matrices are mixing matrices and are the method is further characterized by the method step of: mapping of I A and I T onto O s as follows; let π M be a 6×6 matrix (and π M (i,i) be a matrix element at the i th row and column of the matrix).

Claim 37

Dependent Claim 45 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices are further characterized by the method step of: deriving and implementing, for each of the permissible degrees of freedom of robot motion, the π matrices as follows: ##EQU24##

Claim 38

Dependent Claim 78 words

A control system and method of control in accordance with claim 32 and wherein commands for force and motion are applied to force and motion mixing matrices, and said force/motion mixing matrices are further characterized by the method step of: specifying entries in the π matrices which reflect a desired effect of task representation on shared signal control over said robot; and specifying what is being mixed along a particular direction of motion by entries in said matrix.

Claim 39

Dependent Claim 60 words

A control system and method of control in accordance with claim 33 and wherein said mixing matrices are further characterized by the method step of: sharing signal terms in a feedforward loop established in the matrix (with these stated conditions) as given below: ##EQU25## whereby equations (1) and (2) completely determine C in a feedforward direction in said feedforward loop.

Claim 40

Dependent Claim 52 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices also receive force commands in a force matrix, and said method is further characterized by the method step of: π F for said force matrix wherein entries in said force matrix are constructed as ##EQU26##

Claim 41

Dependent Claim 65 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices are further characterized by the method step of: implementing motion and force sharing in weighing matrices which are designated Ω (motion and force), and wherein said Ω matrices are determined as follows; (Ω(i,i)) is a matrix element located at the i th row and column of said matrix.

Claim 42

Dependent Claim 45 words

A control system and method of control in accordance with claim 36 and wherein said mixing matrices are further characterized by the method step of: summing output signals which are emitted from said matrices in summation circuits connected to the feedforward and the feedback loops.

Claim 43

Dependent Claim 45 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices are further characterized by the method step of: choosing in M and F, some directions for operation under pure teleoperation or pure autonomy, or a mixture of both.

Claim 44

Dependent Claim 48 words

A control system and method of control in accordance with claim 38 and wherein said mixing matrices are further characterized by the method step of: achieving pure autonomy and pure teleoperation within the robot control system by setting W equal to 1 and W equal to 0, respectively.

Claim 45

Dependent Claim 68 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices are further characterized by the method step of: let these be denoted by 6×1 vectors G T and G A ., wherein (G T (i)(G A (i)) is equal to 1 if and only if pure teleoperation (autonomous control) is intended in any given direction which is designated as direction i.

Claim 46

Dependent Claim 65 words

A control system and method of control in accordance with claim 31 and wherein said mixing matrices are further characterized by the method step of: define matrix elements which form the Ω matrices as follows: ##EQU27## where, W denotes the weight assigned as entries in the elements of said matrices, and noting that the elements in the Ω matrices will, in general, be diagonally arranged.

Claim 47

Dependent Claim 114 words

A control system having an autonomous planner and a teleoperator, and a method of control using feedforward and feedback signal commands through the control system in a feedforward path and a feedback path, and said control system comprising: a feedforward path having input and output signals at a task level, with said signals consisting of the following components: ##EQU28## where←indicates what signal information is contained in a feedforward command in said feedforward path; and task level sharing circuitry; and means for inputting actual motions/forces into said feedback path through said task level sharing circuitry in order to generate a motion/force feedback signal for an autonomous planner and a force reflectance signal for said teleoperator.

Claim 48

Dependent Claim 114 words

A control system having an autonomous planner and a teleoperator, and a method of control using feedforward and feedback signal commands through the control system in a feedforward path and a feedback path, and said control system comprising: a feedforward path having input and output signals at a task level, with said signals consisting of the following components: ##EQU28## where←indicates what signal information is contained in a feedforward command in said feedforward path; and task level sharing circuitry; and means for inputting actual motions/forces into said feedback path through said task level sharing circuitry in order to generate a motion/force feedback signal for an autonomous planner and a force reflectance signal for said teleoperator.

Claim 49

Dependent Claim 49 words

A control system and method of control in accordance with claim 42 and further comprising: an autonomous planner which expects the system to track only the autonomous part I 1A , which expectation would result in an incorrect reasoning (upon completion of a commanded task) by the autonomous planner.

Claim 50

Dependent Claim 80 words

A control system and method of control in accordance with claim 43 wherein the control system controls a robot by an actual control signal formed by sharing control between an autonomous planner command and a teleoperator command, and further comprising: the method step of compensating for the fact that the autonomous planner does not know that the actual control signals that are controlling the robot have been a shared command developed from said teleoperator command and said autonomous planner command.

Claim 51

Dependent Claim 66 words

A control system and method of control in accordance with claim 44 characterized in that what is actually being tracked is not solely an autonomous input command but rather is a shared command, and further wherein the autonomous planner may conclude that task execution has failed; and providing a means in conjunction with said autonomous planner for compensating in the autonomous planner for the shared command.

Claim 52

Dependent Claim 68 words

A control system and method of control in accordance with claim 45 and further comprising a task specification for said autonomous planner, and said control system further comprises: means for modifying the task specification of the autonomous task planner from I 1A to O 1s , wherein O 1s is a signal representing a shared motion/force trajectory that is applied to said compensating means for said autonomous planner.

Claim 53

Dependent Claim 42 words

A control system and method of control in accordance with claim 46 and further comprising: means assuring that under pure teleoperation, said task planner specifications are derived from the teleoperator completely and not from any autonomous or mixed autonomous and teleoperator operation.

Claim 54

Dependent Claim 66 words

A control system and method of control in accordance with claim 42 and further comprising the step of: formulating in signal weighting matrices the signals that are applied through said task level sharing means in accordance with the mathematical relationship as follows: ##EQU29## where .sub.λi reflects the scaling factor between the actual forces generated and said force reflectance signal that the teleoperator is intended to feel.

Claim 55

Dependent Claim 29 words

A control system and method of control in accordance with claim 48 and further comprising the additional step of: providing force reflectance of the actual forces to said teleoperator.

Claim 56

Dependent Claim 53 words

A control system and method of control in accordance with claim 49 and further comprising; means for developing a virtual force reflectance signal for said teleoperator as defined by; (G.sub.A).sup.t G.sub.T =0 G.sub.A U G.sub.T =S.sub.M where, U indicates a union operation and S M represents a space of motions allowable by M.

Claim 57

Dependent Claim 38 words

A control system and method of control in accordance with claim 48 and further comprising an additional step of: providing force reflectance by an open-loop, wherein said teleoperator just feels contact of said robot as a reflectance force.

Claim 58

Dependent Claim 45 words

A control system and method of control in accordance with claim 48 and further comprising the additional step of: providing force reflectance by a closed-loop through said feedforward and said feedback paths whereby said teleoperator can effect changes in the desired contact force through teleoperation.

Claim 59

Dependent Claim 37 words

A control system and method of control in accordance with claim 52 and further comprising the additional step of: employing said closed loop only when time delays between a feedforward and a resulting feedback signal are insignificant.

Claim 60

Dependent Claim 86 words

A control system and method of control in accordance with claim 48 and further comprising an additional steps of: developing an inertial term .sup.Λ.sbsp.T M by summing a weighted matrix signal with a modified Motion/Force signal that actually controls the robot; enabling the teleoperator, via said inertial signal, fed back to said teleoperator by said feedback path, to experience the inertia of the robot system at the remote site; and allowing said teleoperator, through such enabling, to get a sense of how the robot is behaving.

Claim 61

Dependent Claim 48 words

A control system and method of control in accordance with claim 54 and further comprising, via the term .sup.Λ.sbsp.T M an additional step of: enabling said teleoperator to adapt to the inertial characteristics of the robot system, so that the teleoperator learns how best to teleoperate the robot.

Claim 62

Dependent Claim 53 words

A control system and method of control in accordance with claim 55 and further comprising, via the term .sup.Λ.sbsp.T M an additional step of: reflecting, in the presence of contacts along directions of contact forces, actual forces back to the teleoperator (as modified by a scaling factor as defined in claim 48 ).

Claim 63

Dependent Claim 53 words

A control system and method of control in accordance with claim 54 and further comprising, via the term .sup.Λ.sbsp.T M an additional step of: obtaining along directions of motions, a difference between the desired and actual teleoperator trajectories; and using said difference to inform said teleoperator about the inertial characteristics of the robot.

Claim 64

Dependent Claim 32 words

A control system and method of control in accordance with claim 54 and further comprising; restricting teleoperative and autonomous motions in the orthogonal directions, so, .sup.Λ.sbsp.T M will be defined as: ##EQU30##

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1995-02-03	1995-08-05	1996-02-04	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1999-02-03	1999-08-05	2000-02-04	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2003-02-03	2003-08-05	2004-02-04	$7700.00	Window Closed / Lapsed

Bilevel shared control for teleoperators

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