Developing A Reliable And Smart Deep Rolling Tool – MFN Interview with the developers
The ECOROLL AG Werkzeugtechnik is a tool manufacturer for tools for mechanical surface treatment. ECOROLL has developed and sold mechanical and hydrostatic rolling tools for many years. This year, ECOROLL extends its portfolio with a machine hammer peening tool, ECOpeen. Within the interview, we spoke with three innovators at ECOROLL about their latest innovation, the ECOsense technology. As CEO Dr.-Ing. Karsten Röttger describes it, ECOsense is a technology for future business models in deep rolling. With the ECOsense technology, ECOROLL enables the mechanical surface treatment for smart factories of the future. It measures the rolling forces, evaluates the processes, and sends information directly to the customer. How they developed ECOsense, what the initial motivation was and what the plans for the future are, MFN discusses with CEO Dr.-Ing. Karsten Röttger, Head of R&D Dr.-Ing. Oliver Maiß, and Digitalization specialist Dipl.-Ing. Florian Uhlich.
(?) MFN: Mr. Röttger, last year your company ECOROLL AG Werkzeugtechnik promoted a smart device for deep rolling tools. What was your motivation to start this development?
(!) K. R.:That is correct. Last year we finally started the rollout of our new ECOsense Technology. My personal motivation was the idea of inventing a smart rolling tool, to help our customers to get more information about their processes and part quality. I started playing around with these small Arduino Kits and programmed some automations for my house. I figured out that this is really a simple technology with great benefits. So, I started a development project at ECOROLL with some external partners. But I think we should start at the beginning!
(?) MFN: That is correct. Maybe you can start with the explanation what ECOsense is and then we will come back to the question if it really was that simple to develop this product?
(!) K. R.: Yes of course. ECOsense is the digital alternative to the analogue gauges on our mechanical rolling tools. Usually, you need to know the rolling forces to achieve a specific rolling result, regarding the surface quality or the surface integrity; e. g., residual stresses or hardness. Conventional mechanical rolling tools use an analogue gauge to measure the spring deflection. As we all learned, spring deflection leads to a spring force that represents the rolling force. What ECOsense does, it basically replaces the analogue gauge with a digital one, but the digital one is a small computer with a microcontroller and some sensors. We can detect processes, identify processes as “not ok” or “ok” and we can communicate the measured rolling force directly via Bluetooth to an external device. But the details can be explained by my employees more specifically. They are the experts, which developed this product.
(?) MFN: Ok, Mr. Uhlich, as developer for digital products at ECOROLL, can you give some more details about the product?
(!) F. U.: Sure, by using a calibration curve we transform the sensor signal from a spring deflection into a specific rolling force. For that purpose, each tool has its own calibration curve. A microcontroller calculates the signals into time dependent rolling forces and transmits the values with a Bluetooth Low Energy connection to an external device. We have stored process limits, as for example a minimum and a maximum rolling force on the microcontroller, so we can evaluate if the process was within or outside the necessary process range. For each process the force curves are also stored on the ECOsense device. In addition to the hardware, we developed an app for Android, which can be used for the communication between ECOsense and the customer. Within the app you can get access to all stored processes on the ECOsense and transfer them onto your mobile device. In the end, you can get documentation for each single process of your production line.
(?) MFN: Ok, I understand the basic technology. It really looks beneficial for your customers. Can you explain why your customers especially need this technology?
(!) O. M.: In contrast to the other important mechanical surface treatment shot peening, deep rolling is a geometrically defined process. Which means we have a lot of information about the processes, just by describing the tool geometry and rolling parameters. However, these are not all influencing variables. For smoothening for example, ECOsense will provide benefit in reducing inspection time for the surface quality. If you must measure each part of your production batch, because you have to achieve a specific window for the surface roughness values, you will save a lot of time if you have all processes out of the parameter range detected automatically. But even more beneficial is the ECOsense for deep rolling processes to induce residual stresses. As you know, measuring the residual stresses without destroying the part is not possible. When you need to know the depth profile of the residual stresses, to assure a safe and reliable function of your part, it is crucial to know the rolling force. The most significant factor in deep rolling for the surface integrity are the rolling forces. Many research projects have identified this. With ECOsense, it is the first time you can document all necessary process parameters for each part.
(?) MFN: And how sensitive is ECOsense by means of force documentation?
(!) F. U.: Rolling force is crucial but not very sensitive for changes. Therefore, we sample and send ten force measurements per second. The frequency can be set higher but to save battery life, we choose a sampling frequency of 10Hz. Additionally, the measured force values are rounded to 10N. This is sufficient for all processes we tested the system with.
(!) K. R.: This is a good point. As you see, we tried to find a balance between accuracy and customer satisfaction or convenience. We did not want any cable, so the tools can be used in lathes with multiple tools and in machine tools with tool magazine. My biggest fear was that the product would not be used due to the required battery changes. The worst case would be the customer wanting to use the device and missing recharging the battery. We started with a battery life of 8h. Now, ECOsense can be used for more than 30 days without recharging!
(?) MFN: Is the Android App the only possibility to access the data?
(!) F. U.: No. It was a good start, but in the end, we must implement the system into future smart factories, cloud systems and industry 4.0 standards. Therefore, we just developed a gateway to communicate with the ECOsense and access the data to a Web interface. Here the beta testing just started with a couple of customers.
(?) MFN: What is your goal for the technology?
(!) O. M.: Our first priority is to satisfy our customers. We know that it is crucial to document the rolling forces, so this means that it is also crucial for our customers. ECOsense gives very detailed documentation for every single rolled part to our customers. Our second priority is to develop more innovative business models. I think that is no secret. A big part for the digitalization of tool and parts is to develop new business models. For example, for us it would be great to pay just for a machined part and not for several cutting tools. This applies to deep rolling where our customers want to get deep-rolled parts and usually do not want to pay for a tool. We all know this from software in Software-as-a-Service- or SaaS-products. We think it would be a sustainable and fair solution for all to apply a PaaS – Process-as-a-Service – system.
(?) MFN: Mr. Röttger, this is very innovative regarding the product development and the business modelling. What makes you so sure, that this is the right way?
(!) K. R.: I am pretty sure: it is the right path we are on. Mr. Maiß mentioned it. Regarding climate change, resource efficiency and machine safety; this all comes to the same topic: Sustainability. As for shot peening, deep rolling is a very sustainable process that increases the lifetime of parts and reduces the weight of parts. That means the use phase of the parts is more resource-efficient. To achieve the same within the production phase, one key could be the circular economy. And by selling processes instead of tools, we can start a circular economy for our deep rolling tools. So, considering all trends of Industry4.0, smart factories, and sustainable manufacturing, I am really sure, that ECOROLL has taken the right path for the future.
(?) MFN: Thank you all for your time. One last question to you, Mr. Röttger. At the beginning, you mentioned that this whole microcontroller thing was a simple technology. What are your thoughts now on this?
(!) K. R.: Good question, I hoped you had forgotten about this! Of course, it is much more complicated as it seemed in the beginning. Playing around with an Arduino or a Raspberry Pi is easy. Building a reliable product is a different story. As a company, we had not had much experience in microcontrollers or software development, but I think we have learnt a lot while making some mistakes. In the end though, we have developed a great product.
MFN would like to thank Karsten Röttger, Oliver Maiß and Florian Uhlich for this interview!