How to meet high quality requirements with manual assembly
Often it is a dilemma. To assemble complex products of high quality, you need highly skilled operators. But yes, because highly skilled operators are less interested in repetitive work, they last less long. In addition, they are expensive and scarce. How do you solve that?
Digital, interactive work instructions offer a solution
This dilemma can be solved by using Visual Factory. With visual work instructions it is indeed possible to make high-tech products of high quality with low-skilled operators. Visual Factory is a software system that is configurable (and extensible) with modules so that it is very widely applicable. You can easily create and adjust work instructions yourself in the software. The latter is especially efficient because you do not immediately need your supplier to make adjustments.
Hands-on training Visual Factory
Total Productivity has used Visual Factory for Brink Towbars in the construction of a new “high mix – low volume” assembly line for electrically operated towbars. Brink's engineers know their product best themselves. They also know best in which order the product should be assembled. It was therefore obvious that they would put together the visual work instructions themselves.
In the training courses (and return days) given by Total Productivity, they immediately started working with their own product, their own BOM (bill of materials), their own tasks and work instructions. Direct hands-on and learning-on-the-job!
No steep learning curve
Basically Visual Factory is an accessible system and does not have a steep learning curve. Both the user interface and the operation are very similar to Microsoft Office and therefore fit in well with what people are used to. The software works intuitively and if you really can't figure it out, there is a support website (knowledge base) with all kinds of videos and instructions. Handy for the engineers who make the work instructions.
But the operators do not need to be trained intensively either. They are taken step by step through the work instructions in the actions they have to perform. These instructions are designed in such a way that certain actions trigger the next logical step.
The system checks, via all kinds of built-in interactions and sensors, whether the operator has performed his actions in accordance with the guidelines. For example, you can quickly put temporary workers to work if there is a shortage of operators. If the operator knows what the steps are to follow, the work instructions can also be set in such a way that they are displayed in less detail.
Integration Visual Factory with the production line
The requirements for the margin of error were high on the production line for Brink. Only 1 in 42,000 products may contain an error (24 ppm). In Brink's production numbers, this is virtually no margin of error (zero defects). It is therefore essential that the towbar components are assembled correctly and in the correct order. Screws with the right torque, barcode actions for the right parts, mandatory execution of certain tests. Everything is thought of.
Brink's production line is full of these kinds of smart tools and tests (in the meantime and at the end) to keep the margin of error as small as possible. These signals are also used as a trigger to present the next step in the work instruction to the operator. As a result, he or she does not have to trigger the next work instruction via the screen.
To achieve this very low margin of error, Total Productivity has established a full connection from Visual Factory to the assembly line. An operator must have performed an action exactly before he/she can proceed to the next step in the work instruction. For example, a screw driver is only released if the previous operation has been properly completed and the control steps have been carried out (Poka Yoke principle).
What is Poka Yoke?
Poka Yoke is a Japanese term that is mainly used within lean manufacturing. A poka is an 'unintentional mistake' and yoke is 'prevent'. This is not about correcting or detecting an error, but rather about preventing the error from ever being made. Poka Yoke is used to organize processes in such a way that making mistakes is almost impossible.
Example Poka Yoke principle
A good example of the Poka Yoke system is a screw machine in the Brink line. For example, the screw driver is only released if the previous operation has been properly completed and the control steps have been carried out.
When the screw machine has been released by the system, the operator is directed via the work instructions to place the correct torx screw on plate A with the correct bit. A pick-to-light on the correct bit, screw and plate is used to visually indicate, via a light, which part should be used. In the Visual Factory system you can then ensure that the screws are tightened with, for example, 6 Nm. If so, the operator can continue with the next step. He doesn't even have to click on the screen anymore. The system knows through the input of sensors or tools that the next work instruction must be displayed.
The assembly line is only as fast as its weakest link. In other words, as fast as the amount of work one operator can do. The work must therefore be well distributed so that the most efficient flow can be achieved. We determine that flow on the basis of a time-sequence diagram. In this way we ensure that everyone on the assembly line has the same amount of work, so that we achieve maximum productivity and output.
Production data is saved
A major advantage of Visual Factory is that all production data is stored and can be retrieved at any time. You can also share this data with the (end) customer. You can even present the real-time data through a dashboard for operators and/or management. Keeping track of production data is mandatory by the end customer in many sectors and can also be very useful. For example, think of:
- Automatic export of order data, quantities and serial numbers to the end customer.
- line balancing; data analysis over a longer period of time makes it possible to distribute work even better.
- Recalls on certain used components or subassemblies.
- Burden of proof for warranty and/or damage claims.
- Track and analyze production issues for the implementation of structural improvements.
Flexible scaling up or downscaling of production
The assembly line at Brink is designed in such a way that it can be operated by one, two or four operators. So you can let the number of products you want to make per day depend on the demand from the market. The capacity is then respectively 25%, 50% or the full 100%. It is expected that the demand for these products will increase and thus a ramp-up will take place.
With this production line not only upscaling or downscaling is possible, but also the line, after workplace two, can be customized for the manufacture of the towbar for a different car brand.
After assembly station two, the product on the line is provided with a thin grease track. This trace of fat should be exactly the same on every product, with the same dose. To achieve this, Total Productivity has built in a cobot that applies this track. Such a cobot can do this much more accurately than a human can and is therefore the ideal solution to deploy in this location.
What is a Cobot?
a cobot (collaborative robot) is a robot that physically interacts with people in a workplace. This means that this robot can work autonomously next to and/or together with people. Cobots (usually) have a limited size and make limited movement, which means that they can work safely in the vicinity of people.
Knowing more? Then view our pages about operator support systems.
The line exceeds our expectations
The production line developed and made by you is currently being built by us and exceeds our expectations.
Congratulations and thanks to your team for the professional construction and cleanliness / details in the finish. The cooperation in recent years has been constructive and professional, which means that we have come to this result together.
We look forward with confidence to seeing the production line up and running in the coming weeks and then producing our first larger series.
Director Product Development
Brink Towing Systems BV
Interested in digital work instructions for your company?
Would you like to know more about Visual Factory and digital work instructions? Or do you have productivity improvement goals?
Then feel free to contact us.