The Story Behind Our Controller Design – Part 2
In this 2nd installment of the story behind our Controller design blog series, we cover additional facts and considerations, features that weren’t introduced in the 1st part, and add some color to the happenings behind the design process.
Future-proof
Forecasting is very difficult, especially when it’s about the future. Some of the biggest breakthroughs and even crises – no matter the domain – have occurred without a warning. While recognizing these limitations we wanted to make the Controller as future-proof as possible.
What this means in practice, you might ask? Good question and we are glad you asked. As specified in the 1st part, our Controller is placed on the right-hand-side, therefore replacing the traditional shifter which is made obsolete by our design. Instead of adding more ‘stuff’ to the cockpit area, we choose the route of simplification. Less is more. Meanwhile, the right-hand-side placement leaves real estate for other controls, such as a dropper post lever which is a standard issue in e-mtb’s. Also, if a new technology comes along that requires input from the rider and therefore a human-machine interface (HMI, for short) that needs to be placed in the cockpit area, we have plenty of space available for it.
Ever-increasing connectivity is the direction we are going towards. Terms like Big Data and IoT (Internet of Things) are thrown around left and right on a daily basis. We wanted to make ourselves ready for widening the bandwidth of information by equipping the Revonte ONE Drive System with the latest technology when it comes to connectivity. Naturally, this includes the Controller as well.
Modular Structure
One very neat feature that we did not purposefully uncover in the 1st part is related to the modular structure. As can be seen from the photos, our Controller uses paddle-like levers which can be easily used with the thumb only, warranting the expression; rule of thumb. This is an important feature that reaches all the way to the level of safety. Index-finger should be free all times for braking purposes.
Back to modularity! The Controller is built with a modular structure that enables swapping the part that forms the actual surface for the HMI without sacrificing the water tightness and reliability. In other words, the levers can be detached from the Controller and replaced with a modular component that transforms it into a twist shifter. Although this shifter type has fallen out of favor in non-motorized bikes, there are clear benefits for e-bike applications. Or simply going completely without an option to manipulate the cadence or gears and let the motor do the work for you.
With the stepless and automatic function of the Revonte ONE Drive System, the twist shifter makes a lot of sense. For example, when running the non-automatic indexed mode, the twist shifter enables the use of truly stepless transmission and gear change.
In our experience, the trigger model is a good fit for performance-focused type riding (e.g. e-mtb) where intuitive and highly honed actuation is required. Correspondingly, the twist shifter is a good fit for casual type or riding, like commuting in city areas. One benefit to mention is this type of shifter simplifies the cockpit and is very easy to use. During Eurobike 2019 we had several inquiries if a twist shifter type of Controller will be available later on. We were happy to provide an answer that was satisfactory.
One More Thing About Going Screenless
As you’ve learned from the previous part, we decided early on to take the screenless route with our Controller. This matches our minimalist philosophy when it comes to the cockpit area.
Even more important is that by doing this, we leave the choice of freedom to the bike rider. Running the tidy and elegant look that we offer is the default option, but nothing prevents the rider – or the bike manufacturer – equipping the bike with the screen of choice and interacting with it by the Controller. Offering compatibility with the major head unit manufacturers is one of the reasons why we have considered the connectivity issue thoroughly.
Screen technology is progressing rapidly with leaps and bounds on an annual basis. If the rider wishes to use a screen, our solution enables the use of the latest technology whenever preferred. It is also worth mentioning that our App provides an ample amount of ride data and post-ride diagnostic options as well. Running a screen does not require the purchase of an additional head unit since we have harnessed the power of the smartphone for the task.
Running your e-bike with or without a screen – the choice is yours.
It’s All About DFM
DFM stands for the design for manufacturing, which is an essential part of product development. It’s one thing to make a good design and produce a handful of units accordingly. Oftentimes, it is a completely different game when the needs of high-volume manufacturing are taken into account. Some of the basic questions are:
- Manufacturability. Is the design easy enough to manufacture with the costs allowed? Is the manufacturing process simple and robust enough to produce consistent quality?
- Materials. The materials used need to be up for the task. For example, there are many, many types of plastics and some of them might be a very good fit for the Controller as others might be so brittle that the first push of thumb produces a snapped lever.
- Tolerances. Dimensions and tolerances need to be defined early in the design process. Ensuring that the materials and manufacturing methods can reach them reliably is another thing that might throw you in the iteration loop for several rounds. Defining the driving dimensions (i.e. the measurement that is essential for the design to work) is also a part of this step.
- Quality control. The design and manufacturing processes need to create a pair that produces quality parts consistently with the dimensions specified. Easy in theory, oftentimes much harder in practice. Quality control is the last line of defense in ensuring that only the components that meet the stated criteria leave the factory.
- Costs. This point brings all the steps together. One design might be superior in many ways but is too costly to manufacture. One thing worth pointing out is that the costs go up and down considerably when moving into high-volume production. Producing a high-quality product with the highest consistency and a competitive price tag is the ultimate goal of the design process.
In the end, it’s not all about DFM, but it is an essential part of the design process that can not be overlooked.
That’s a small peek behind the curtains when it comes to our Controller that forms the HMI in the Revonte ONE System. Hope you enjoyed the read and found it interesting.