# Design of Cognitive Assistance Systems in Manual Assembly Based on Quality Function Deployment
## 6 Discussion and Limitations  
### Discussion  
The research challenge is, on the one hand, the fact that the design of cognitive assistance systems is a complex task due to the multitude of technologies and the possibility of different levels of assistance. On the other hand, both the company's requirements for the work process and the workers' requirements must be considered and correlated with the technological possibilities and assistance levels. The goal for the design of an assistance system is the benefit for the optimization of a work process and the acceptance of the workers to use it. Therefore, the goal of this research was to develop a method to enable \begin{table}
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**Requirement** & & & & \\ (W: Worker Perspective; E: Engineering Perspective) & & & & \\ \hline W: Order transparency: overview of orders and shift-based overview & - & Assistance system provides a transparent overview of the orders and particular sequence; No searching time for the right order and no time for sequencing the orders; & - Increased personnel productivity through eliminated searching time; Increased delivery performance by ensuring the correct sequence; \\ \hline E: Clear monitoring of all assembly steps (not realized in prototyping phase) and picking steps & - & Waiting time for system too long; W: Manual confirmation by pressing button after pick unnecessary; W: Experts should be able to switch off picking assistance; E: Incorrect picking or the picking of the wrong quantity cannot be detected; & - Increase in assembly time as worker (especially experts) has to wait for the system; Quality improvement through prevention of picking errors; \\ \hline Push information regarding changes or special notes & - & It is very good that changes and special notes are displayed automatically; E: The confirmation of the change notes by the worker is good because of compliance; & - Quality increase because no special notes or changes can be overseen; \\ \hline E: Clear work instructions and test procedures & - & Textual and picture-based visualization are a good fit; the textual one might be more suitable; It is positive that the assistance functions distinguish between beginer and expert level—less information is displayed for experts; W: Forced guidance regarding assembly sequence not good -> Allow sequence in process segments to be freely chosen; E: E: Forced guidance regarding assembly sequence good; W: Navigating between the individual assembly steps not possible; W: Automated translation of the type code for worker; & - Quality increase through standardized assembly; Cycle time spread between different workers is reduced due to the standardized assembly; \\ \hline Easy access to additional information & - & W: Good possibility to access detailed information, such as drawings, BOMs, etc., easily at the push of a button; & - Quality increase by detailed information in unclear situations and avoidance of misinterpretations; \\ \hline Automatic documentation & - & E: Advantageous that all documentation of values measured and number of pieces as well as manual confirmations are automatically processed by the system; & - Reduction in lead time because no manual documentation is required; Quality increase as it prevents incorrect values and information from being documented or in case the documentation is missing; \\ \hline Integrated testing & - & Good that measurements can also be instructed by the assistance system and can be controlled by it; & - Quality increase as measurements are performed in a standardized procedure and operating errors are avoided; Time reduction as no documents or information have to be searched for; \\ \hline \hline \end{tabular}
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Table 5: Evaluation feedback overview (excerpt). systematically design cognitive assistance systems that integrate both company and worker requirements in a participatory way. The research was approached by design science research.