6.5.3 Teleoperation Manipulator Technology Much of a teleoperator's capability is sensory; much is associated with manipulation. Although configurational details require further definition of task requirements, overall general-purpose space teleoperator characteristics can be partly inferred. A teleoperator arm must have enough freedom so that the manipulation and arm locomotion systems can position the hand or end-effector at any desired position in the work environment. There must also be a locus of points which all of the teleoperator's hands can reach simultaneously. If such a region does not exist, manipulator cooperation is precluded -cooperation and coordination of multiple manipulator arms and hands give teleoperators (and humans) tremendous potential versatility. How many manipulator arms might the general-purpose teleoperator have? Despite man's two arms, the teleoperator will probably need three. Most mechanical operations require just two hands --one to grasp the material and the other to perform some task. A third hand would be useful in holding two objects to be joined, or in aiming a television camera (or other appropriate sensor). In many two-handed operations on Earth the human worker moves his head "to get a better look" -the third teleoperator arm would move the man's remote eyes for that purpose. Indeed, the third arm can be used to couple the TV motion to the man's head motion. Bradley (1980) notes that this gives a strong feeling of telepresence. Finally, three fingers probably are sufficient for duplicating most of the functions of the human hand -this is the minimum number necessary for a truly stable and controllable grasp of small objects.
6.5.4 Robot Systems Teleoperators will always be vital to many operations in space because they extend man's senses and motor functions to remote locations. But extraterrestrial exploration and utilization and other advanced systems will require remote autonomous systems --systems with on-board intelligence. These robot systems will evolve along with current AI efforts at representing knowledge functions in a computer. The integration of AI technology with teleoperator/ robot systems is a major development task in its own fight and should be timed to support space programs that require this capability. Aspects of artificial intelligence which must be addressed in regard to robot systems include memory organization, knowledge retrieval, search, deduction, induction and hypothesis formation, learning, planning, perception and recognition (Lighthill, 1972; Nilsson, 1974; Sagan, 1980; Winston, 1978). Teleoperation and robotics technology requirements are: time lag compensation methods, sensory scaling, adaptive control methods, touch sensing, hands, hydraulics, actuators that are many times lighter than the masses that they lift, onboard power for autonomous operation (this is a major problem), parallel computers, clamp and hold servoing of arms (extra hands are needed to hold parts while soldering and connecting), homeostasis, survival instincts, world models, laser data links, and laser sensors. Computer science, cybernetics, control theory and industrial process control are all relevant fields in this research. Interactive systems are being developed whereby the computer works, not autonomously, but as a partner or intelligent assistant. Kraiss (1980) discusses the design of systems resulting from cooperation of human and robot systems in four specific areas -computers capable of learning and adapting, computer support in preparation and evaluation of information, computer support in decisionmaking, and computer assistance in problem-solving.
6.5.5 Telefactor Technoh)gy Development Recommendations The advantages of the availability of telefactor systems for development of subsequent fully automatic and replicating systems have already been described in this report. However, it is worth noting that: (1) all of the technical information and components to build a telefactor system were available, and the basic subsystems (e.g., master-slave manipulators and head-aimed television systems built and demonstrated) before 1965, and (2) to date, no one has built a complete system (Bradley, 1967). Construction of a standard telefactor system is long overdue. NASA should include this important step in an early phase of its automation program. Some of its applications to the NASA program are the following: 1. A telefactor system can be used to oversee and operate a materials processing activity to establish requirements for full automation of such activity and also for manned intervention. 2. A telefactor system can provide a built-in maintenance and repair facility in a complex pacecraft. 3. A telefactor system could perform satellite inspection, modification, or other EVA operations from the Shuttle, even with uncooperative objects. 4. All of the actions and observations of a telefactor system can be taped for later playback, permitting retrospective task analysis. 5. Demonstration of the frequently proclaimed versatility and effectiveness of telefactor systems is overdue and much needed. 6. A standard telefactor system can be used as a comparison-piece in the field of robotics. Differences in task performance and in characteristic deficiencies among telefactors versus robots would be of great interest. 7. Since computers can be readily inserted into a standard telefactor system, these could become powerful tools in the development of fully automatic or supervisory control systems.
