Fast and accurate robot based machining, finishing or cleaning of surfaces of geometrically complex manufacturing parts requires the introduction of flexible sensor based automation concepts. The industrial robots currently available on the market can not comply with such advanced requirements. In this paper a new concept for managing such challenging robot tasks is presented. It relies both on a flexible continuous slip and force control algorithm as well as on the use of a new slip sensor which is able to measure relative motion between the robot end-effector and the machined object surface. The smart slip and force control concept is applied to a robotic arm finishing the surface of an unfixed randomly moved object. Both theoretical approach and experimental results of ongoing research are presented in this paper.

Within the next years a new generation of humanoid robots able to manage autonomously sophisticated tasks in a complex, time varying domestic and public environment is going to be developed. To cope with these advanced requirements a new multi-sensor based discrete- continuous supervisory control concept is proposed, which is able to accomplish even complex human skills. Each skill is divided into a sequence of elementary actions (so called Primitive Skills). Depending on the multi-sensor perception of the current state of the system, the discrete control has to provide an optimal selection and activation of the appropriate sequence of action and control strategy. An on-line decision making algorithm based on the structure of Primitive Skills (PS) has been implemented. On a lower level the continuous control has to assure that each PS is performed by means of the most appropriate sub-controllers. The theoretical approach and first experimental results of the ongoing research are presented in this paper.

Within the next years a new generation of humanoid robots is going to be developed being able to manage autonomously sophisticated tasks in a complex, time variant domestic environment. To cope with these advanced requirements a new multi-sensor based discrete-continuous supervisory control concept is proposed, which is able to accomplish even complex human skills. Each skill is divided into a sequence of primitive skills (PS). Depending on the multisensor perception of the robot state, the discrete control has to provide an optimal selection and activation of different PS. On the other hand the continuous control has to assure that each PS is performed by means of the most appropriate sub-controllers. Both theoretical approach and experimental results of the ongoing research are presented in this paper

In order to reach optimal drill penetration using a rotary hammer, it is necessary to control the two variables, rotational speed and strike rate, of the rotary hammer in such a way that by applying minimal guidance and recoil power, a maximum drill penetration rate can be achieved in the rock. An optimal drill penetration rate is attained through using a given combination of rotational speed and strike rate. Changes in the drill diameter and/or material hardness lead to a false adjustment of the system which has to be re-optimized by an intelligent re-adjustment of the two servo-controlled drives. To achieve a flexible and automatic adaptation of rotational speed and strike rate of the rotary hammer to different material and tool types, an adaptive multi-sensor drive control based on a self-learning neuro-fuzzy component has been developed by IITB in cooperation with an industrial partner.

The automation of complex industrial batch processes is a difficult problem due to the extremely nonlinear and variable system behavior or the conflicting goals within the different process phases. The introduction of a single multiple-input multiple-output controller is not useful because of the rather high design effort and the low transparency of its complex structure. A more suitable hierarchical fuzzy-logic (FL) based supervisory control concept is proposed. It permits the decomposition of the complex control problem into a series of smaller and simpler ones. In the upper level of the hierarchy the FL-based supervisory controller classifies the actual process phase in terms of the available process sensor signals and activates dynamically the appropriate situation specific low-level controllers. The paper presents the generic concept of the FL supervisory controller that comprises both a FL process diagnosis and a control mode selection as well as experiences with the industrial application.

The automation of complex industrial batch processes is a difficult problem due to the extremely nonlinear and variable system behavior or the conflicting goals within the different process phases. The introduction of a single multiple-input multiple-output controller (e.g. fuzzy logic, FL, controller) is not useful because of the rather high design effort and the low transparency of its complex structure. A more suitable hierarchical FL-based supervisory control concept is proposed in the paper. It permits the decomposition of the complex control problem into a series of smaller and simpler ones. In the upper level of the hierarchy the FL-based supervisory controller classifies the actual process situation in terms of the available process sensor signals and activates dynamically the appropriate situation specific low-level controllers. The generic concept of the FL supervisory controller which comprises both a FL process diagnosis and a control mode selection as well as experiences with the industrial application are presented in the paper.

Up to 20 percent of the German sewerage systems are damaged mainly due to their high age. The estimation for the restoration costs is about 100 billions DM. As a consequence the German Government has issued comparably harsh environmental laws enforcing the owner of a sewerage system to check regularily its state by means of suitable inspection technology. However, at the present state of the art the inspection systems available on the market which are dominated by rather simple TV technology can not sufficiently comply with the qualified inspection demands. For closing this gap, in a joint R&D project with 4 partners from industry and research institutes the advanced multisensor robot inspection system KARO has been developed and prototypically realized which is able to detect automatically type, location and size of damages in the sewerage system. The modular system concept comprises both a high-resolution color TV camera and a multisensor system consisting of innovative 3D-optical, ultrasonic and microwave sensors. Thus, the robot is enabled online to detect and classify anomalies during the robot motion within the pipe or the pipe wall respectively as well as within the closer pipe surroundings. Moreover, the robot optionally comprises a navigation sensor module for exploration of a priori unknown sewerage topology during the robot motion. For sensor fusion and damage classification a new fuzzy based concept is applied.

Different approaches of a learnable fuzzy-logic (FL) concept for highly fast and accurate position control of industrial robots are presented which provide both time-optimality for large position errors as well as well damped response (no overshoot) near the target. For automatic optimization of the control parameters an additional neural-network component is introduced. Based on simulation and experiments the performance and robustness of the presented FL concept are discussed.

A novel mechatronics concept for decentralized vibration control by means of an active absorber is presented. In order to achieve a high dynamic accuracy without spill-over effects an integrated model-based overall optimization both of the hardware and software parameters and of the local placement of the absorber onto the most sensitive points of the mechanical structure is required. Suitable methods both for the experimental model identification and for the structural and parameter optimization are presented. The performance of the mechatronics concept applied to a SCARA type robot is demonstrated by experimental and simulation results.>

A substantial increase in the robot velocity can only be achieved by introducing light-weight composite materials for the mechanics and gearless motor drives in order to substantially reduce the joint inertia, However, a light-weight robot carcass results in structural oscillations which have to be removed by the additional introduction of advanced model-based control structures and concepts. A new mechatronics concept is presented in which structural end-point oscillations are damped by means of a decentrally controlled vibration absorber. Representative simulation results applied to a high-precision SCARA robot confirm the efficiency of the concept.>

A novel sensor-based concept for automatic generation of IR (industrial robot) motion programs that provides high dynamic accuracy even in the case of complex workpiece contours is presented. The concept is based on sensor-controlled contour scanning and successive data reduction that depends on the tolerance band and velocity profile demanded by the IR user. By introducing an efficient tool vector notation for describing TCP (tool center point) orientation, the quality of programs generated is considerably improved. The method, which has been implemented on a commercial control system in a real environment, represents a very efficient tool for drastically minimizing the setting-up times of the IR. The performance of the concept is illustrated by some practical results.>

A concept called predictive functional control (PFC) is presented for industrial robot (IR) control. It provides excellent control performance, a high accuracy even for fast trajectories, an outstanding tracking quality for sharp contour deviations, and a very good robustness with respect to parameter variations. It is shown that PFC can be implemented on conventional IR control systems. The performance is demonstrated by several experimental results.>

An industrial robot (IR) position-control algorithm will be presented that was developed at the Fraunhofer Institute for the highly accurate cutting of geometrically complex metal surfaces. In the past the extreme tolerance requirements for hard alloy workpieces had to be met manually or by means of expensive specialized machine tools. It is shown that this advanced manufacturing task can be solved by a conventional IR if its elastic behavior can be sufficiently stiffened by the introduction of a more sophisticated control concept. Experiences with the design and the practical implementation will be discussed.