What makes a particular platform suitable or unsuitable for production use?

Question

Let's assume that the cost of goods is an insignificant factor. If a company lacks a team to produce a custom board for a particular product, but has success with an off-the shelf development platform like Arduino / Netduino / mbed, what sorts of things should be considered before going forward?

If I'm not mistaken, Arduino was originally targeting university students because of its low price and ease of use. It naturally became a popular platform for artists and makers. I see the Netduino as a logical extension of Arduino -- it allows people to use a robust and rich IDE (Visual Studio 2010) and get things done quickly via the .NET Micro Framework. mbed is another nice hobbyist platform because of its ease of use, free tools (online compiler), and hardware peripherals.

So my question is, why shouldn't companies adopt these development platforms for production usage? In other words, is it a bad idea to just buy several boards from Sparkfun, program each of them with the code, and then deploy the product to customers?

I'm specifically interested in Netduino, but arguments for / against Arduino and mbed are also welcome. On the flip side, would you, or have you done this before?

I personally look at the Netduino development as a "core module" that other processor manufacturers sell for product integrations, but maybe I'm missing something important here.

Answer 1

Yikes! Either you're thoroughly confused, or your idea of production is different from mine. I consider production to mean selling a product to the general public in quantities of thousands or more, then supporting and updating the design. Products which don't go to the general public are either internal or contract work, and products which sell in smaller quantities are special-purpose or otherwise different. 'Several boards from Sparkfun' wouldn't fulfill a production need.

First, the cost of goods is always a significant factor. Just how significant it is may differ from product to product, and it may be less significant if the particular item is only a small component of a larger system which has been optimized for cost. However, in any environment where you're in competition with other producers (which you must be because if you're in government or have a monopoly you wouldn't be asking this question), cost will be a factor. The $35 for the Netduino (in cost alone) could usually be reduced to $10 or less for most applications with a custom design. If you are convinced that the cost doesn't matter, there are further reasons against buying such a design.

Yes, all three boards were designed for students, designers, and hobbyists. They are designed to be reliable enough for a development kit which sits on a desk. That student should know a few things about safe handling procedures which the general population does not know or practice. Issues such as ESD, long-term power dissipation, and component derating were likely demoted below things which are less important for production like solderability and simplicity.

Your affinity for IDEs and prepackaged solutions is frightening. In my opinion, you place way too much trust in your tool providers. If the boards become more expensive, if the license terms are changed, if the server goes down, the software is declared obsolete, the board manufacturer goes out of business (etc. etc. etc...), your business is hosed. Also, you lack an understanding of what's going on behind the scenes. If something doesn't work the way the documentation says it should what is your plan? Your idea to buy a few Arduinos, program them, and deploy the product, for example, lacks any plan for code protection. Someone else could copy your code out of the microcontroller, duplicate the relevant parts of the design for a third the price, and outsell you.
Relying on an IDE and language for the stuff you don't understand is a recipe for disaster.

Using a development kit in your design will make your product overpriced, fragile, bulky, power-hungry, and inefficient. It will also be hard to debug, a pain to support, and you'll be at the mercy of your suppliers. It will make you look incompetent.

However, all is not lost. If you implement your design on a development board, it will be straightforward to have someone (either on or off your team) customize it to remove these deficiencies. If you lack a team, you should hire one, bring in a contractor, or have it done by a design firm.

Answer 2

Some of the things you might look at when sourcing a controller module are issue such as security of supply over time, any licensing issues, any inefficiencies in firmware loading process for production, any code security issues, and any manufacturing quality or regulatory compliance concerns. Some of those are going to be more of a concern for a proprietary module than a relatively open one you could have someone else make an equivalent to or eventually merge with other functionality in your product.

Answer 3

I have use an Arduino board in a product (not large scale production) and I wouldn't do it again. The Arduino boards are geared towards a very closed ecosystem (in the non open-source software meaning of the word). For instance, if you 'step out' of the Arduino ecosystem by needing to use a pin that isn't brought out to a header on the development board, you immediately lose all the benefits of the Arduino. You have to modify the board to bring the pin to an existing header or add a new header somehow. This likely means you won't be able to use any existing shields or possibly even the software libraries for the Arduino. That's most of the benefit of the board gone. I have had to do this with an Arduino Mega.

Also, the boards are huge and not easy to integrate with other PCBs I made the main board for my application equivalent to a shield for the Arduino Mega that had mounting holes for the enclosure I chose. So I just plugged the Arduino Mega into the headers I put on my board. However, this was a lot of up and down size to accommodate, and there was a lot of wasted space due to the size of the development board. I didn't need half of what was on there and it only took up room. This required me to have a larger PCB and enclosure than I otherwise would have needed. That's wasted money.

Answer 4

Arduinos &co are prototyping and evaluation platforms. As such, they are simply not economically viable as a basis for even relatively small production runs. They're great for education and mocking up ideas, but a product would sink very quickly if it had to carry the cost of a ready-made sub-assembly that was not optimal in its final use.

It would be far better to create a new board including required elements of the 'duino and any ancillary circuitry than to have the cost of two boards and the risk of failing connections.

With regard to Visual Studio and anything .net, I wouldn't touch them with someone else's. Go for something platform and manufacturer agnostic - kind of in the spirit of the Arduino project itself.

Answer 5

Generally speaking there is nothing wrong with using off-the-shelve products. We all do this at some level, I guess the Arduino-haters don't design their own chips, even tough at some higher volume level that would make economic sense.

It always boils down to cost, schedule and quality (and maybe long-term availability too). If an Arduino meets these criteria better than a custom board, the choice is a no-brainer.

The difficult part is to get the right figures, especially for your volume. But using the correct figures and little math will give you the break-even volume for the choice between uising let's say the Arduino versus a custom board. If that is way beyond what you expect, or way below, the choice is easy. So forget all advices that say either "by all means use an Arduino" or "always go for a custom board", they are both locked into a mindset that belongs to a specific volume level. Do your own calculations.

Note that I have no specific knowledge of the Arduino. You will have to decide for yourself whether it meets for instance your quality requirements.

Answer 6

Custom made boards are nice if you have a budget for this and production big enough to justify the work. Otherwise you stick with products of the shelf, like Arduino, Netduino, Fez Domino, and SBC boards (like in PC104 and various ITX formats). Making custom AVR/Arduino board is not too complex, but heavy modifications to Netduino or even designing (and later supporting) some linux board (like Gumstix) need a specialist(s) and cost tens of thousands of dollars and more. If you want to have most of the hard work done by someone else, and you want to customize just some parts of it, then module is the magic word for you.