How It Works

It all starts with a phone call. We have customers that call us from all over the world!

The goal of the first conversation is to determine exactly what the customer is looking for. We use this information to come up with a design plan. This design plan details the look and finish / materials to be used, type of communication protocol that will be implemented and the methods we will use to build it. The most important piece of information that starts the conversation is a sketch of what the customer is looking for. This could be a detailed drawing or a simple napkin sketch.

project sketch rendering

Our customer was able to provide us with a beautiful rendering of the touch keypad assembly. With this drawing we could now have a very productive conversation. This rendering allows me to think about all of the requirements, from the different color uniform lighting to the mechanical shape and thin form factor that is required. This rendering also made it obvious to us that the customer needed some type of mechanical housing to pull off the full look and feel that they are looking for. Since the electronics/graphic and lighting overlays and the mechanical housing designs all must fit together perfectly, it is very important that all of this design work is done simultaneously. Once we discussed all of the aspects of the design requirements, we put together a design plan. This design plan basically summarizes our conversation and shows the customer our true understanding of what is required for their new product. For this project, we put together the following design plan:

  1. We are going to use our PCB type capacitive touch keypad. This means the PCB will have the touch pads on the top surface of the PCB and all of the necessary electronics on the back side of the PCB.

  2. The customer wants to use RGB LEDs to uniformly light the graphic overlay. This meant that we could use our LEDs that have the all 3 color (red, green, and blue) dies in one led. Doing this would save a considerable amount of space. Our lighting layer is a special laser etched or imaged layer that allows the light to uniformly glow underneath the graphic overlay. The thickness of this lighting layer would be 1mm.

  3. The graphic overlay will be made so that it is scratch resistant and have opaque and translucent inks. The customer is interested in using glass or polycarbonate for the material. The thickness of this will be 0.030” or 1mm chemically strengthened glass.

  4. We will have to use a special mechanical mounting method in order to assemble this correctly. Male or female PEM fasteners can be used.

  5. The communication method will be half duplex RS-485 as well as standard low side driver control using NPN transistors.

  6. A custom GUI interface will be used for the setup and demo control of these capacitive touch keypads. The customer has a trade show that they are attending in a couple of weeks and needs some way of showing all of the keypads working together as well as being able to change the colors of the lighting. This same windows application software can be used to do acceptance testing of future production keypads.

  7. A mechanical design review is needed to determine the best mechanical mounting method for the different private jet interiors. A GoTomeeting will be conducted so that the customer can see my Solid Works 3D Cad desktop as I design different possible solutions.

  8. The mechanical parts must be aluminum so that they can be polished and plated with precious metals, like gold, silver, chrome etc. We will use the FDM process for initial prototypes and then have one of our partners’ 3D print metal parts.

This design plan was approved by the customer and the work began. We only had a couple of weeks to make this happen as the customer wanted to show this off at the NBAA 2013 Business Aviation Convention & Exhibition The customer was very excited because not only were we able to commit to finishing the design and building the prototypes on time for their show, but that our prototypes will look like and feel like the real thing! Even our electronics are machine assembled. Their customers attending the show will not be able to see that these are the first prototypes. They will look like actual production parts! Now for the fun part! I want to walk you through the following design process:

It is very important that the electronics, graphic and lighting overlays, and mechanicals are designed simultaneously. Doing this ensures that the complete assembly will fit together correctly the first time. After all, we don’t have time to for mistakes! We use Altium Designer because it allows me to make my schematic, PCB layout and 3D mechanical design of the PCB all in one software environment. The 3D mechanical part can be easily imported into my Solid Works 3d design so that I can check for interferences and make sure everything will fit and work the first time. Altium designer also directly communicates with our pick and place line making the assembly of the prototypes. The first thing we design is the electrical schematic. My software engineer and I work closely together during this design phase. It is important that what we make can be programmed to do what the customer needs. The next thing I do is layout the electronics. At the same time I will design the graphic overlay and lighting layer using Corel Draw.

3d project pcb
3D design of the capacitive touch keypad PCB
3 button layout alto design
Vector artwork made using Corel Draw
vector artwork made using solidworks
Complete Assembly of Capacitive Touch Keypad includes the PCB, Uniform Lighting Layer and Graphic Overlay

During all of this, the 3D mechanical design must take place. We will put the entire model / assembly together and make sure everything fits correctly. I will then send my pcb files out for fab and get ready for the production of these prototypes. I will use our laser to create the custom lighting layers and the graphic overlays will be reverse printed on the correct materials. Once the PCBs arrive, I can solder all of the components using our surface mount pick and place assembly line.

Here is a video of this in action! Like this video? Click here to view more like this! youtube

Once the PCBS are made, we will inspect all of the them to make sure they are 100% perfect using our Mantis Elite. Now we will complete the assembly by adding the lighting layer and graphic overlay. This assembly will now be taken into the software lab where my software engineer will bring this beautiful prototype to life! For the first time, I get to see this keypad light up in the different colors.


red pcb lighting
green pcb lighting
blue pcb lighting

It is amazing to finally see all of that work come to life!

3d printed metal cover
3D printed metal cover in place

Each button is tuned for perfect sensitivity with the metal enclosure in place to make sure we account for any possible interference from the surrounding components.

windows gui software
Our Windows Application GUI software is used to connect to each keypad via half duplex RS 485

Once we have tuned the keypad we will then test all of the communications / lights / buttons using our custom GUI software that was created for this project. Our customer will be able to use this software to demo the keypads at their tradeshow. Being a full prototype design house specializing in capacitive touch interfaces made Rapid Keypads the best choice for completing this design in such a short period of time. Our talent, software and equipment have been assembled to give our customers that fastest “Looks Like, Feels Like” prototypes in the world!

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