Computer Vision
Manual assembly processes digitized
The main focus of Industry 4.0 is on the intelligent networking of machines. Human work in production, on the other hand, is often still measured and analyzed using antiquated methods. Computer vision and artificial intelligence can remedy this.
More than 100 years after Frederick Winslow Taylor founded ergonomics, human assembly activities are still largely observed and measured manually. The consequences are a lack of information, incomplete data sets, observation biases and a lack of system perspectives in manual assembly processes. Considering that over 70% of assembly activities worldwide are still carried out by human labor, the Industrial Internet of Things has a huge, man-made blind spot here.
The status quo can be changed by technologies that revolutionize the methods of time and motion studies and eliminate the shortcomings mentioned above. Drishti, together with some of the world's leading manufacturing companies, including those based in Europe, is playing a pioneering role here.
Image 1: AI-based motion detection: After a short training phase, the software reliably recognizes individual work steps in assembly processes.
© DrishtiCameras are positioned above each station of a manual assembly line. This provides customers with live and recorded video. Within a few days, Drishti's neural networks analyze the video streams and generate cycle time data, which customers then integrate into their production systems. Everyone in the plant - line workers, team leaders, manufacturing and quality engineers, and plant managers - can use the solution to improve decision-making. This leads to higher production quality, greater efficiency and better training.
Video streams instead of static images
While there are now numerous services in the field of static image recognition, Drishti analyzes video streams. A practice that the company refers to as motion detection. To do this, the technology has to cope with different scenarios: Variations in part size, the inaccurate placement of workpieces, different motion paths, multiple units in the field of view, camera occlusion, different physical characteristics in workers, and changes in lighting or background.
Figure 2: A view of the variability at workstations: For each data point, the corresponding video can be called up with one click. Drishti offers a comprehensive analysis of standardized work steps in real time, for example in response to the questions: Where are capacity bottlenecks? Where is waste occurring?
© DrishtiNumerous features have been introduced to overcome these challenges:
- An almost completely unsupervised learning function enables accurate data generation with smaller data sets and a 10-fold reduction in training time compared to other methods.
- Thanks to 3D Convolution, Artificial Intelligence not only considers individual frames, but also the time aspect between them. In this way, Drishti achieves significantly higher accuracy than other solutions.
- Using occlusion detection with memory capability, the AI anticipates what is happening behind an object that is obscuring parts of the camera's field of view. For example, if a normally visible tool is obscured, the AI deduces from the movement of the visible arm holding the tool what is happening in the non-visible area of the image.
- To create tangible added value for customers, a fully integrated system architecture, a video pipeline and a data science engine were created.
Videos on root cause analysis
The deployment of the solution begins with the identification of a use case at the customer's premises. After the project kick-off, the cameras are installed and connected to Drishti's cloud via a secure VPN connection. This can also be done by the customer's employees on site. In the following weeks, the AI is trained to recognize the process steps of the selected assembly lines. In close cooperation with the customer, the employees learn how to use the tools in their daily work to achieve their goals. The first successes in the customer's continuous improvement processes can usually be quantified within a few weeks of the start of the project.
Concrete benefit
The existing processes for investigating customer complaints are time-consuming and expensive. Since Drishti's database is connected to the customer's MES, the assembly process for each individual product can be traced in detail at a later date and the videos are easy to find. This reduces both the time and cost of investigating customer complaints: A German automotive supplier, for example, speaks of an average saving of the equivalent of 10,000 US dollars in one of its plants in Mexico.
Another positive aspect is the increase in productivity through continuous process improvements. The technology is always 'on' and therefore provides insights into production processes with human involvement on a scale and at a speed that was previously difficult to imagine. The data obtained on individual work steps and cycle times is processed clearly and systematically by the AI. Customers can quickly identify the causes of waste and define measures to eliminate them. One example: German automotive supplier Hella deliberately used Drishti on a line that was considered to be optimized in order to test the performance of the technology. Using conventional methods, it was no longer possible to identify new potential for improvement. With the help of Drishti, increases in throughput of up to 7% and system availability of 4% were achieved within ten weeks.
The author: Georg Stieler is a member of the management board of Stieler Technologie- & Marketing-Beratung and advisor for Drishti Technologies.
© StielerThe technology also creates interesting use cases for training assembly workers. With easy access to video recordings and data, it is easier to differentiate between good and bad processes and design training courses accordingly. This has enabled customers to reduce defect rates and rejects by double-digit percentages. While static image recognition, which is now widely used in quality control, helps to detect quality defects, Drishti helps to find out how they came about and how they can be prevented in the future.
Anonymization of employees
Typical objections to the use of cameras on assembly lines are the possible identification of workers and the attitude of employee representatives. While Drishti's original market, the USA, generally has less strict
less stringent guidelines than the European GDPR, powerful trade unions, particularly in the automotive industry, are demanding similar data protection.
To protect the privacy of assembly workers, an edge-based application is used in the cameras that masks the people in the videos in real time. The software does not collect personally identifiable information (PII). This allows the systems to be implemented in accordance with existing data protection guidelines or GDPR-compliant. The first applications are being used by German automotive suppliers in Eastern Europe, and preparations are underway for deployments in Germany.
The assembly workers themselves also benefit from the videos and the data collected by the AI, as they receive reliable data instead of subjective snapshots. Suggestions for improvement are given a more reliable
basis for discussion and potential sources of danger can be identified. In numerous cases, assembly workers have used Drishti to prove that errors occurred through no fault of their own. The system's video traceability has helped to identify the real causes of errors.


















