Individual warning using electric signals

在有潜在危险的环境中（如铁路轨道、道路施工现场、集装箱内或在不清晰的设施中进行维修工作）的劳动情况，需要员工在发生危险时进行可靠和个人的警告，以便他们能够安全进入。目前最先进的是具有光学（如信号灯）、声学（如警报器）或极少有振动信号的警告系统。当信号感知受到干扰或各种环境影响时，就会出现问题。一种新的研究方法涉及到可以使用纺织品可靠而容易地将电信号应用于皮肤表面。总体目标是建立一个功能齐全、符合法规的警报系统，该系统基于电刺激，满足个人用户的要求。因此，需要对刺激技术进行研究，并且必须确定刺激阈值以可靠地检测电信号。在我们的工作中，我们研究了电刺激的可感知性，同时尽量减少对功能的损害。这种创新的研究方法是对现有研究方法的补充。然而，没有标准，因此在第一步中，必须探索性地开发知识库。基于4个工作假设，在项目的第1阶段，第1部分，我们能够证明在实验室条件下，通过电刺激的方式进行预警是可能的。在不同信号形式的大量实验中，建立了保证可靠预警的合适信号类型。为了确定基本的感知阈值，一项基于68名带有粘附电极的参与者的研究忽略了诸如气候、工具、工作姿势或PSA等干扰影响。因此，可以定义三个阈值：感知阈值-注意阈值和不容忍阈值。此外，采用不同电极设计的纺织品功能模型的概念也得到了发展。在项目阶段1第2部分中，要研究感知阈值，即必须评估考虑上述影响因素的信号感知。此外，还将研究在多个电极上对时空模式的感知。为此，计划建造一个特殊的实验室空间，用于模拟环境影响（温度、湿度、空气运动）。为了确保结果的可比性，研究最初将按照项目第1阶段第1部分使用粘接电极进行。根据功能样品（第1部分），套管将由测试人员制造和检查。阈值是未来发展使用电信号的预警系统的基础。随后，即在项目第2阶段，将调查长期影响和习惯影响。

Labor situations in potentially dangerous environments (e.g. railway tracks, road construction sites, in containers or during maintenance work in unclear facilities) require the reliable and individual warning of employees in case of danger so that they can get themselves into safety. State of the art are warning systems with optical (e.g. signal lamps), acoustic (e.g. sirens), or rarely, vibratory signals. Problematic situations arise when signal perception is impeded by distractions or various environmental influences. A new research approach involves electrical signals that can be applied reliably and easily to the skin surface using textiles.The overall goal is to establish a functioning, regulation-compliant warning system based on electrical stimulation that meets the requirements of the individual user. Thus, research into stimulation techniques is required, and stimulation thresholds must be determined to reliably detect electrical signals. In our work, we investigate the perceptibility of electrical stimulation, while simultaneously minimizing impairing functional effects. This innovative research approach complements already existing ones. However, there are no standards so that in a first step, a knowledge base must be developed exploratively.Based on 4 working hypotheses, in project phase 1, part 1, we were able to show that warning by means of electrical stimulation is possible under laboratory conditions. In extensive experiments with different signal forms, suitable signal types ensuring a reliable warning were established. A study was carried out based on 68 participants with adhesive electrodes in order to determine the basic perception thresholds, neglecting interfering influences such as climate, tools, working postures, or PSA. As a result, three threshold values could be defined: - Perception threshold- Attention threshold and- Intolerance threshold.In addition, concepts for textile functional models with different electrode designs have been developed.In project phase 1, part 2, the perceptual thresholds are to be investigated, i.e. signal perception under consideration of the above-mentioned influencing factors must be evaluated. Furthermore, the perception of spatial-temporal patterns on multiple electrodes will be investigated. For this purpose, the construction of a special laboratory space for the simulation of environmental influences (temperature, humidity, air movement) is planned. The study will initially be carried out with adhesive electrodes in accordance with project phase 1, part 1, in order to ensure comparability of the results. Based on functional samples (part 1), sleeves will be manufactured and examined by test persons. The threshold values are the basis for the future development of a warning system using electrical signals. Subsequently, i.e. in project phase 2, long-term and habituation effects will be investigated.