Developing Process of the PowerControl 7: Interview with Peter Rosenland

Peter, you are the developer of the new SRM PowerControl 7, which is on the market since last week. Can you tell us something about the process of development - from planning to first prototypes and to the production of the first series for the market?

Cycling enthusiasts, especially triathletes, have often asked for a PowerControl which would fit between the aerobars. This was the motivation for developing the PC7, because the PCVI - like the PCV - being 80 mm wide, is too wide to fit.
The minor size was challenging because of the energy supply. The nickel metal hydride technology had reached it's limits in the PCV and PCVI so we wanted to improve it.
To guarantee the simplicity of the production process, it is a top priority to cooperate and work hand in hand developing the housing and the electronics. So I worked very closely with Christoph Adels, who is responsible for the 3D-modelling. If there were changes to the housing because of design or functionality I adapted the electronics.

When the housing and electronics were passed the basic process of development, we produced our first prototypes. These prototypes were handed out to specific teams and athletes for testing to identify the first teething problems before planning the serial production.
The last step was to give the final production parameters to our suppliers, who assembled the circuit boards and produced the cavitiy moulds for the housing. This was also the time when Stefan van Kempen, our purchasing manager, took care that we had enough batteries, screws, etc for the serial production.

Professional cyclists like the riders of Team HTC Columbia got the prototypes of the PC7 very early. How does this help in developing?

Professional athletes and coaches have the highest demands for the reliability of the product and the data.
That's not always easy for both sides. The athletes want a product that always works and needs no awareness, best described as "plug and play". We try to make that happen, but prototypes can cause problems. That causes discussion and frustration when something is not working perfectly,for the athletes and for me, when the comments are not always fair and the description of the problems is sometimes a little vague.
But all the reviews and suggestions are a very important part of the development process. That's why I am very thankful to all of the beta-testers of our prototypes, especially the pros who test our hardware and software under extreme conditions.
And only if everything works well we can start to produce for our customers.

What are the most important innovations in the PC7 in your opinion?

We have tried to keep the good characteristics of the PCVI, like the easy to read display and the simple menu navigation with just three buttons but added some innovations. We integrated a motion sensor, to automatically start the PC7. The 4pin plug is changed to a standard mini-USB plug. Now you can download and charge the PC7 with standard cables. The new lithium polymer battery is the latest technology with less weight and good capacity. With about the same energy consumption of the PC7 to the PCVI the battery lasts about 4 times longer now - that's 120 hours of riding.

Is there something you did not integrate intentionally and why so?

We have not integrated GPS, because the energy consumption of the GPS chipsets on the market is still high. It was more important for us to enlarge the runtime of the battery. The same problem would be for example a backlight of the display.

During the development process of a product there are always new ideas which come up but cannot be implemented - because of technical issues, costs or time. Is there something you can think of right now? Do you have an idea for a PowerControl 8 already and what could it look like?

The whole process from the scratch to the final PowerControl takes about two years. So there might be a new version in the next three years.
There are ideas for our next version, like graphic display, to vary and simplify the menu and the setting.
We also think about making our new product downward compatible so PowerControls for the wired systems can be replaced. Our PowerMeters are very long lasting and also customers who already have a wired version should benefit from our innovations.