Where does the prototype start?

    Good Friday everyone!
    I would like to tell a little about how prototypes are created. I am sure that many have encountered this and know how to do it by hearsay, it is unlikely that you will learn something new from this article for yourself. This article is intended for those who are just starting their journey in DIY (do-it-yourself) and is designed to structure a little fragmented information.
    image


    So, you decided to make some kind of device. Usually it all ends with this thought, but sometimes it becomes the beginning of something larger, surprising and beautiful. It’s not so important why you decided to make your device, rather than buying something ready-made - it is unique, not like the others, you dreamed about it, decided to realize your childhood dream, could not find what suits you best - the reasons are the most different, the main thing is that the decision is made.

    Before you begin designing and making your dreams come true, you need to decide on a few points - the presence / absence of moving elements, whether you will collect it from what you have or will not regret the effort and money for new parts, budget, time, etc.

    A device with moving elements (a small robot, a machine tool, a mousetrap) is a very interesting topic, it should be considered separately and in detail. Here a lot depends on the material from which you want to make elements. Naturally, the simplest and least time-consuming option is to print them on a 3D printer. laser cutting is best suited for sheet materials. If the material is dense and the product is voluminous or has many technological holes, it is worth ordering its manufacture on a CNC machine. If this is something “designer” use plastic for prototyping.
    image

    Prototyping from existing parts is both more complicated and simpler. For example, you have 18 printers lying in your garage, 2 toasters and an old router, and you want to make a 3D printer out of all this, a hexapod, and a Steampunk vase for your wife from the rest. All this, of course, is a good thing, but in practice, alas, only a few have enough spatial thinking and a technical look to see all this rubbish in the form of a set of parts and imagine how they will be combined in a future design. Usually it all comes down to the fact that out of 18 printers we get 3 bags of parts, the whole floor is strewn with screws and after that it is easier to take these bags to the trash than to figure out what to do with them.

    Budget and deadlines are sometimes key. Not many of us are ready for the dream of a robo-cockroach to buy components for 2-3 thousand dollars and to mess with it for six months. Usually the idea is either realized within a few weeks or hopelessly forgotten (postponed for the distant future, when there will be more time, money, opportunities). But, however, the criterion of budget-timing plays a crucial role. You can consider it a criterion for the survival of the project. If you do not mind the time to rethink the project so that its price becomes lower, and the number of errors during implementation is less, then the likelihood that the idea is successfully implemented becomes higher.

    As Suvorov used to say, “Theory without practice is dead,” so let us begin with illustrative examples.

    Summarizing all of the above, we can draw the following conclusions:
    1. When creating a prototype, you must make the most of existing elements and details. This will reduce the cost of construction
    2. If the available elements are not enough - use ready-made blocks that you can buy in stores for hobbies and amateur radio.
    3. If possible, avoid making boards yourself (especially controllers) - this is very cool and interesting, but if this is your first experience, it can seriously undermine morale and morale, as well as put an end to the future prototype. In addition, it is difficult to find the necessary components. If the use of off-the-shelf modules and blocks is not enough, use solderless breadboards.
    image
    4. Always leave the opportunity to upgrade the device and the "margin of safety" of the elements. Do not do anything “back to back”.
    5. Before assembling the entire device, check the operation of individual elements. Read datasheets.
    6. If you are not sure about the device’s performance, do not neglect CAD programs. Drawing models, debugging circuits and firmware will save you time, money and nerves.

    I want to tell a little about my experience. A few years ago I was asked to design a device to control the load of alternating current (it seems it was some kind of perverted lighting system for a storefront) with a timer on. Photos unfortunately did not survive, instead I will try to describe in more detail. The task was not too complicated, and to create a prototype of the device, I decided to use ready-made modules. As it turned out later, it was the best solution.
    Because time and budget were far from endless; I decided to use modules from the electronic designer Master KIT (now undeservedly forgotten). These designers are of course a little expensive, but almost do not need additional configuration after assembly, and there were no other alternatives at hand.
    Arduino with the ATmega32 controller was taken without thinking twice as the main controller.
    image
    I chose the NK150 module as the lighting control unit (only the relay was set based on a more powerful load).
    image
    In order for the showcase to work on a clock basis, a real-time module similar to BM9319 was added .
    image
    As for the hardware, everything was perfectly coordinated, I had to tinker a bit with the firmware, but this did not take much time either. In any case, doing from scratch each element would have to bother a week over the assembly and a couple of weeks over debugging each device individually, searching for errors, searching for similar rakes on forums, etc. Having packed everything in a beautiful box and received the rest of the money from the customer, he traditionally expressed a desire for further cooperation. We continued to cooperate after a few months. A new backlight appeared on the window and, accordingly, it also needed to be automated. Rejoicing in my forethought, I simply stretched the wires from the new backlight to the relay terminals. After a month, 2 more of them appeared, as a result, 7 of the 8 relays were busy. Then a dedicated Internet line appeared, and with it the need to manage the window remotely (in case of sellers forgetfulness, so that you could forcefully disconnect it remotely). This, too, turned out to be easier than simple - I connected the Arduino USB port to the printer USB port of the router.
    For readers, it will probably be interesting to find out how I configured the router, gateways and which one I uploaded the firmware. But this is not my story, because the system administrator of the customer was engaged in setup of a router and access.
    Perhaps the scheme will seem rough, clumsy and not at all ideal for specialists (if not worse), but it worked well and stably, worked out the money spent on it many times, I added additional modules several times and everything continued to work just as stably without additional tricks for almost a year (until the customer’s business is bent).

    Thanks and links

    If you passionately want to create, create and test devices and mechanisms, you should turn to the following resources of
    RadioKot
    Roboforum
    Master KIT
    EasyElectronics and special thanks to DIHALT
    RoboCraft

    P.S.
    I am sure that everyone has their own experience in creating devices, it would be interesting to learn about him. If you meet any inaccuracies or disagree with anything, express your constructive opinion.
    For beginners, I want to say again that my methods are not the only true ones, but they have proven themselves more than once in practice. Creating a new device is incomparable pleasure, an opportunity to feel your capabilities and test yourself. To some extent, this is freedom, because you can translate into reality almost everything you can imagine! And following these simple rules you will minimize disappointment from failed projects and more often you will experience joy and freedom.
    Thanks for attention!

    Also popular now: