The measurement of the absolute rotational angle and torque via sensors forms the basis for many industrial sectors. Until now, combined sensors have not been available, so that a lot of installation space is occupied by sensor setups. In addition, the sensor setups get expensive quickly. Therefore, an optical and non-contact measurement method to detect the absolute angle of rotation and torque was developed. This paper presents the validation methodology, the setup of the test bench and the validation results. With an angular resolution of 0.001 degree and an accuracy of more than 0.05 percent, the results are promising. However, for industrial application further investigations on determining torque and miniaturizing the optical setup are required.
absolute angular position, angle difference, sensor, torque
This paper describes the production process of serially arranged hybrid steel parts, produced by combining a laser welding process with a subsequent cross wedge rolling process. The presented results are only a first approach in order to get first insights in the forming behaviour of laser welded and cross wedge rolled parts. The investigated material combination is C22 (1.0402) and 20MnCr5 (1.7147). This innovative process chain enables the production of hybrid parts. To evaluate the developed process chain, the weld and the joining zone is analysed before and after cross wedge rolling. Main results are that the joining process using laser welding enables a strong bonding between the two materials with a higher hardness in the joining zone than for the individual materials. After the forming process, the bonding of the joining zone is still present, while the hardness decreased but remains higher than of the materials themselves.
tailored forming, laser welding, hybrid parts, cross wedge rolling
An essential component of belt conveyor systems are the support idlers. Particularly in bulk material handling systems, which are used in demanding terrain with numerous gradients as well as under extreme environmental conditions in tropical and arctic regions, they are exposed to considerable stress. The steadily growing flow rates mean higher loads and speeds for the support idlers. This trend is countered by new drive concepts. For example, belt-driven conveyor systems with internally installed motors are used.
Within a research project, the IPH is developing a dual measuring system that can be used to test both conventional bearing rollers and driven bearing rollers.
driven idlers, test rig, efficiency of conveying systems
The measurement of torque via sensors as well as the generation of torque form the basis of many industrial sectors. Within a research project an optical and non-contact measurement method to detect the absolute rotation angle and torque was developed. For comparison with the current state of the art torque sensors a test stand was built and compared to a reference torque sensor. The results of this validation are presented in the present paper.
torque, rotation angle, optical, validation
In order to improve the overall efficiency of production facilities through the use of automated guided vehicle systems (AGVs), the availability of the AGVs has to be high. Failures of AGVs have to be minimized. However, if a failure occurs, a successful disturbance management is crucial. Especially for producing companies, economic losses can occur, if material is not at the right place at the right time. Delays can be a hazard to the adherence to delivery dates. In this research project, a support system is developed that automatically generates strategies for the handling of disturbances.
AGV, expert system, automated guided vehicles, case-based reasoning, CBR
A combined measurement method for the optical determination of the absolute rotational angle and torque was realized. Absolute codings of the angle as well as proper production technologies for the production of suitable markings on the shaft were investigated and successfully implemented.
The absolute rotational angle could be measured with a resolution of about 0.001° at an accuracy of better than 0.2° (corresponds to 0.05% f. s.). Torque was determined with an accuracy of about 3% f. s..
The conclusion is that the overall aim was achieved.
optical measurement, torque, absolute angle of rotation
This paper proposes a method for the automated generation of roadmaps for AGVs. So far the roadmaps are mostly generated manually, which leads to long and laborious planning phases. The presented method incorporates both mathematical roadmap algorithms as well as human knowledge in the form of a fuzzy inference system. The results of the expert system are evaluated in comparisons to the A* algorithm and to manually generated roadmaps on a real production layout. In both cases the expert system performs better.
fuzzy logic, expert system, AGV, roadmap
Automated guided vehicle systems (AGVS) have become indispensable in advanced production facilities. Due to significant progress in the field of automated guided vehicles (AGVs) and the increased automation within production plants, the potential applications for AGVs increase. The design of the roadmap for automated guided vehicle systems is a time-consuming process which is currently performed manually for the most part. Because of the AGVs increasing degree of complexity a manual design of the roadmap becomes more and more difficult and challenging. In the course of the research project “Automatic design of the roadmap for automated guided vehicle systems” (IG 18007) a software demonstrator was developed which allows the automated generation of the roadmaps for AGVS. The software demonstrator was applied to real reference scenarios and it was proven that the automatically generated roadmaps are as reliable as the manually generated ones and in some cases even more efficient.
fuzzy logic, expert system, AGV, roadmap
In this article, image processing of a binary single track code for determining torque is presented. The aim of the research is to determine the absolute angular position of a shaft and the applied torque. For capturing an image of the binary code two independent imaging modules are used, both allowing for measuring the angular position and rotational speed. Combining both imaging modules, torque can be determined. Position markings are directly applied on the shaft using a laser to ensure a simple integration of the system into any application. The selected technological approach is based on a contactless measurement method using angle differences. The concept of image processing as well as first research results are presented for determining the angular position twice and, thus, the torque applied to the shaft.
image processing, single track code, torque
Regarding the handling of complaints by customers, 8D reports are used for analysis and correction of errors that occur in the production process. However, the quality of these reports is often inadequate and leads to longer processing time and errors. Due to time and capacity restrictions in most cases, 8D reports undergo inadequate internal quality testing. Consequently, the aim of optimizing internal processing fails and poor 8D reports with insufficient solutions are sent to the customer. In this paper, we describe problems with faulty 8D reports in detail, and then present a system that automates quality checking of 8D reports based on these facts. This paper focusses on the basic structure of the developed system and how it improves the quality level of 8D reports within the complaint handling process.
complaint, quality management, 8D method, 8D report
In this article, a combined contactless measurement method is presented which is based on angle differences. The aim is the development of a combined, optical measurement system to determine the angular position of a shaft and the applied torque on it as well as an appropriate production technology to apply markings. Two independent modules are used which separately allow the measurement of angular position and rotational speed and if combined can measure torque. To ensure a simple integration of the system into any application, position markings are directly applied on the shaft using a laser. The selected technological approach is based on a contactless measurement method using angle differences. The concept as well as first research results are presented.
absolute angular position, angle difference, contactless combined measurement, sensor, torque
Automated guided vehicles (AGVs) with autonomous behavior and decentralized human-machine interaction (HMI) are suitable for use in logistics. To facilitate natural interaction, HMI may involve both speech and gesture control. This paper presents a new cognitive approach based on electroencephalography (EEG) for multimodal HMI combining speech and gesture control for AGVs used in logistics. The results indicate that implicit EEG-based measures such as alertness and relaxation significantly affect speech control performance. Consequently, monitoring the user's cognitive workload during logistic operations may lead to a substantial improvement in work performance.
logistics, cognitive robotics, electroencephalography
In multistage hot forging processes, the preform shape is the parameter mainly influencing the final forging result. Nevertheless, the design of multistage hot forging processes is still a trial and error process and therefore time-consuming. The quality of developed forging sequences strongly depends on the engineer's experience. To overcome these obstacles, this paper presents an algorithm for solving the multi-objective optimization problem when designing preforms. Cross wedge rolled (CWR) preforms were chosen as subject of investigation. An evolutionary algorithm is introduced to optimize the preform shape taking into account the mass distribution of the final part, the preform volume and the shape complexity. The developed algorithm is tested using a connecting rod as a demonstration part. Based on finite element analysis, the implemented fitness function is evaluated, and thus the progressive optimization can be traced.
preforming optimization, hot forging, evolutionary algorithms, cross wedge rolling
In today's production and logistics systems automated guided vehicle systems (AGVS) play a central role for the Realization of a powerful internal material transport. Through the use of cognitive technologies industiral trucks should be enabled, similar to humans, to respond flexibly to changes in physical environment and organizational changes in the workflow. This creates interactive AGV, which are superior to currently available conventional AGV because they can adapt their behavior independently and flexibly to changing production environments and requirements. As part of this the current high implementation effort for AGVS can be reduced at the same time.
AGVS, gesture control, voice control
Automated guided vehicle systems (AGVS) are an example of high-performance production systems in intralogistics and in many areas of internal material transportation. The essential function of an AGVS is the automatic control of automated guided vehicles (AGVs) which can be equipped with application-specific load handling devices ( e. g., telescopic forks or lift tables). Therefore an AGV is used in different application fields such as pallet transport, installation or commissioning. In this project, a speech and gesture control and autonomous navigation for AGV are implemented.
AGV, speech control, gesture control, autonoumous navigation
Automated guided vehicles (AGVs) with autonomous behavior and decentralized human-machine interaction (HMI) are suitable for use in logistics. To facilitate natural interaction, HMI may involve both speech and gesture control. This paper presents a new cognitive approach based on electroencephalography (EEG) for multimodal HMI combining speech and gesture control for AGVs used in logistics. The results indicate that implicit EEG-based measures such as alertness and relaxation significantly affect speech control performance. Consequently, monitoring the user's cognitive workload during logistic operations may lead to a substantial improvement in work performance.
logistics, cognitive robotics, electroencephalography
Within the research project "Situational behavior control for interactive, automated guided vehicles" a voice and gesture-based control concept was developed and implemented on an automated forklift truck. Based on an industrial application the economic value of this system is to be reviewed in the context of a material flow simulation.
gesture control, speech control, automated guided vehicles
Within this article a decentrally controlled, intelligent material flow system is presented. The novel product routing is based on a decentralized intelligence and conducts the route planning of the individual materials. The decentralized intelligence permits an expansion or adaption of the production line at any time without significant configuration. In addition, the networked decentralized intelligence allows a parallel flow of material and information, and an identification of the layout of the entire conveyor system. Another core element is the decision-making cognitive conveyor, which is composed of small-scale conveyor modules. In addition to transporting, injecting and ejecting a variety of intralogistics functions can be solved with the cooperation of these conveyor modules. For this cognitive conveyor a drive solution is presented that meets the requirements in terms of functionality and compactness.
Decentralized Intelligence, Material Flow, Cognitive Conveyor, ProductionML, Routing
In this article a small scale, cyber-physical conveyor system using the example of a cognitive conveyor is presented. This cognitive conveyor is modularly assembled of individual conveyor modules that are smaller than the transported units. Furthermore the cognitive conveyor is in the position to handle different intralogistical functions such as transport unit's transporting, rotating, buffering and sequencing. Parallel to the route of the physical transport unit, a data shadow is moved: Hereby all data describing the transport operation are available at any time of transport. Cognitive conveyor's control is decentralized and distributed. Hereinafter both the hardware setup of the conveyor modules and the necessary control algorithms are described. The control algorithms are on the one hand used to move the physical transport unit on the surface of the cognitive conveyor. On the other hand it is utilized to align the data shadow with physical transport unit's information.
cyber-physical conveyor technology, decentralized control, material flow, ProductionML
The condition-based maintenance of a marine gearbox poses special challenges because of the inaccessibility to the hull of the ship and harsh environment in the form of higher temperatures, continuous vibrations and salty sea air, which can lead to corrosion. In this article, the integration of a wireless sensor network with a marine gearbox is shown. The integration consists of sensor nodes that record characteristic measurement data, send them actively to a receiving unit and harvest energy from the environment for electrical supply after a one-time installation expenditure. The developed sensor node has a thermoelectric power supply that allows measurement intervals of less than 20 minutes. The recorded vibration data from the gearbox surface are sent via ZigBee wireless technology. By evaluating the envelope spectrum of the measured vibration data, the current rotational speed of the input drive shaft could be identified.
energy harvesting, thermoelectric generator, wireless sensor network, condition monitoring
