Proof of Concept
The Proof of Concept (POC for short) is a project phase that lets you take a closer look at your design. While not all projects require a POC phase, most will.
An idea in your head is a good start, but generally, you will want to create a mock-up of your design to test, show others and get more feedback.
When you do need to go through the POC phase, it is a critical one. Your POC will allow you to have a closer look at your project, and to see if you need to make adjustments. Does your children’s toy sing when you want it to? Does the RFID sensor pick up the card when expected? Does your motor control system provide enough feedback to the user, or should you add lights? A POC will allow you to use your design to see if anything is missing, or if there are components that serve no purpose.
Another use for a POC is to let others get the feel of your project. These people can be friends who can give feedback on the idea or investors who can be seduced by your project. A friend can use your design, and you might find out that he has a different way of using it. Maybe you will have to change your design a little bit? Maybe you didn’t think of everything the first time? That’s fine, changing or adding components to a POC is often trivial. For investors, if a picture is worth a thousand words, a working product in front of their eyes is often worth a few thousand more.
The POC phase is fairly messy. You will be creating a physical version of your idea, but don’t be frightened by its appearance. We will be using readily available bords using microcontrollers and microprocessors that have nothing to do with the final design. Just because your current design uses an Arduino or Raspberry Pi doesn’t mean that your final design will.
I mention Arduino and Raspberry Pi; several POCs are designed around these devices. They allow for fast electronic prototyping; they are inexpensive and easy to program.
In the first phase of a POC, you will be using an evaluation board. Arduino, Raspberry Pi, STMicroelectronics Nucleo, or any amount of easily accessible boards. Your sensors and actuators will probably be small printed circuit boards with a few electronic components on top. Between them, you will probably have a breadboard, a plastic board where you can connect jumper cables and components. Using a breadboard makes connecting external components trivial, but it does have the disadvantage of making the design fragile. It is easy to disconnect a cable by mistake, and the chances are it won’t survive a long trip on a train or airplane.
During this phase, it is extremely easy to change components. Do you want a larger display? It takes seconds to wire a new one in. Do you need to add a few LEDs for user feedback? No problem. Is the temperature sensor not accurate enough? Then let’s try out a new one and see how it goes.
Phase two is a little different, we will still be using the same boards, but we will place them inside a box, or on top of a piece of wood or metal. This makes the design more robust; by soldering wires, you now have a product that you can move around and show people. The design will be considerably larger than the final product, but that’s OK! Friends and investors can easily understand that this huge design will be scaled down to a connected plant pot in the redesign. Size and shape aren’t important in this phase, functionality is.
On the subject of functionality, not everything will be integrated but will be shown. For example, if your product is a desk that sets its height according to the person that approaches, then you won’t be walking around with a full-sized desk to show investors. Instead, a few motors placed on the demonstrator will show the movement. If the wireless communications installed are rated for up to a kilometer, then a visual separation of the width of your hand is normally enough. Remember, we are showing an idea, not the full product.
Some sensors will be tuned to vastly different values. If your project is to create a sensor to read the temperature of a barbecue to help with cooking, then you won’t be showing a reaction to a red-hot fire. Instead, you can show the effect with just a lighter for a second or two, the values will be programmed to react to something much cooler. Safety first!
Once the POC phase is over, there are a few things to do. Your idea works, people love it, but now we need to make it more professional. Each individual component will be evaluated, especially the microcontroller. Once that is done, then a printed circuit will need to be made.
During this phase, several things can happen.
One of your POCs might be changed to integrate a new microcontroller board to allow your development team to start working and get acquainted with the tools needed.
One of your POCs might end up on a wall, or in a demo room. Once you have sold tens of thousands of devices, you can look back and remember where it all started.