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DO-RA: Preparing for Industrial Production

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1. Transporting prototypes

The idea of the DO-RA project originated in March 2011 after a nuclear disaster on the Fukushima Daiichi nuclear power plant in Japan. This gadget was conceived as a personal dosimeter/radiometer working with eponymous software (DO-RA.Soft) on mobile platforms (iOS, Android, WP) as well as on desktop platforms—Windows/Linux/MacOS.

At the end of 2017, a tourist from China brought in his backpack ten long-awaited prototypes from the DO-RA.Q test batch. They were manufactured in China based on our design documents and then transported from Shenzhen to Moscow. By the way, the development of design documents was assigned to the largest Design Centre in Eastern Europe—the PROMWAD company. The documents were clear and plain—prepared in IPC format and written in proper English—to enable the automated production of electronic devices in a foreign country.

Previously, air carriers obstinately refused to transport the smartphone gadgets that we had ordered from China because they contained lithium-ion batteries. By the way, all modern devices that we use in everyday life have such cells, and that's no big deal.

It is well known that the restrictions on the bulk shipping of lithium-ion batteries were adopted by the ICAO* on 1 April 2016. These regulations stipulated that all air carriers transport such goods with cargo aircraft due to the supposedly higher fire hazard of these batteries. The mass use of LI technology in electronic devices shows that from a statistical point of view, the probability of such combustion is essentially zero.

Thankfully, these restrictions do not usually have any bearing on the personal transportation of these batteries.

* The International Civil Aviation Organisation (ICAO) is a UN specialised agency. A protocol on its recognition was signed on 1 October 1947 and came into effect on 13 May 1948. ICAO is an international governmental organisation. Initially, after the signing of the Chicago Convention, a Provisional International Civil Aviation Organisation, PICAO, was established.

2. Errors of Chinese piecework production

Hands of skillful developers can bring any device to life, even if it is incorrectly soldered or almost «ruined». This was the case for our DO-RA.Q prototypes made in China.

In the beginning, we revealed that the resistance value was ten times higher than we wanted; these resistors were soldered into the print circuit boards of our devices. For this reason, we were unable to launch any device at all. Next, we discovered that the device had a Zener diode incompatible with the Design Documents. As envisioned by the developers, it was supposed to limit the operating voltage of the ionizing radiation detector in the electronic circuit.

Furthermore, visual inspection showed that one of the DO-RA.Q prototypes had an overheated printed circuit board. As a result, the microcontroller unit mounted on the board was fried, and its performance fell below the expected level. The measurements of the clock frequency showed that it was about two times slower than other prototypes. Alas, this is human factor!

On the other hand, we thought that accidental overheating of the microcontroller unit could be compared to the tests of our device in extreme climate. It proved the ruggedness of our gadget in case of significant temperature jumps in aggressive environments.

3. Russian manufacturer of DO-RA

In the middle of 2018, at one of the Russian electronic exhibitions, the operator of the DO-RA project—Intersoft Eurasia —met the Russian investment and manufacturing partner, Sarapul Radio Plant JSC. The parties signed a licensing agreement for the mass production of DO-RA devices: up to 12,000 units in 2018 and up to 120,000 units of various models in 2019. It is worth noting that this is the oldest radiotechnical enterprise in Russia.

The history of the Sarapul Radio Plant started in 1900 in Saint Petersburg, where the German citizen Otto Treplin founded an enterprise that assembled products for the Russian market from components made in Germany. The C. Loretz Plant was producing telephone and telegraph equipment for the mass market.

After the start of World War I in 1914, the plant was sequestrated and transferred under the command of the General Military and Technical Directorate. At that time, the enterprise produced Morse-type telegraph devices and field telephones and repaired many types of military communication equipment, which was continuously brought in from the front.

The start of the Great Patriotic War opened a new page in the eventful history of the Sarapul Radio Plant. On 28 November 1941, the Moscow Electromechanical Plant No. 203 was evacuated to Sarapul. Due to the wartime, the production was set up in short time frames. Starting from February 1942, Sarapul Radio Plant launched mass production of radio equipment for the front.

The Sarapul Radio Plant promptly designed and manufactured the molds for the DO-RA.Q housings, purchased the main electronic components from the Russian vendors and released a pilot batch of 150 devices. It turned out that in terms of the component base and skilled labour, production in Russia began to look more profitable than in China. Taking into account the Russian mentality, the lack of a language barrier and customs procedures in the DO-RA production cycle, the unnecessary obstacles disappeared.

4. Verification of user software

A pre-production batch of electronic devices can be manufactured only after meticulous testing of all the aspects of the device: electronic circuit design, electronic component reliability, mechanical and temperature tolerance to overloads and other loads on the product to be manufactured. An important task in such trials is checking the reliability of embedded software and user applications. If users discover equipment malfunctions after the start of sales, the manufacturer will get many claims.

We chose the iOS mobile platform to be the first for software testing. For historical reasons, our pioneering product—DO-RA.Soft for DO-RA-branded devices—was developed for this platform first.

Some time ago, we came up with a rational idea: moving to the Corona universal platform, which enabled seamless operation on both iOS and Android. Unfortunately, the morning sun never lasts a day: the company that develops this universal platform has left the business, losing its investor just before the start of 2019.

5. Testing for iOS

As usual, the first bug wasn't discovered in the DO-RA.Soft user application code: it was caused by a standard pin of the USB charging cable and revealed by our leading iOS developer, Vadim Bashurov, when he started tinkering with the device. Thus, we confirmed once again a fundamental truth of electronics: it's all about contact!

It is worth noting that when our project began in 2011, the iOS application was written in Objective-C, a language familiar to programmers from all over the world. All libraries in this language were written in advance, and all the functionality was laid out in the DO-RA.Soft user application.

However, science and technology do not stand still, and all the world's programmers in seeming unison started switching to Swift** 2.0, then to 3.0, 4.0 and finally to 5.0! We had the hardest time moving from Swift 2.0 to 3.0 as the language changed fundamentally. By the way, now Apple does not recommend using the AudioUnit 7.0 library and its higher versions: the company wants the developers to master new programming languages. Nevertheless, there is no official ban on Obj-C because numerous program resources and applications are still based on the Objective-C code.

Of course, we also spent some time testing DO-RA.Q and included the identified problems in the Design Documents for the device. The manufacturer was informed about the audio jack standard, and the programmers were told about the new system for transferring the signal from the device to the smartphone.

For example, the radiation detector based on the Geiger-Muller counter had quite high noise, and therefore, programmers and circuit designers had yet another problem to solve: measuring the natural background radiation emitted by Earth. It meant tracking the ionising radiation in the range from 0.1 to 0.35 μSv/h, which is considered a «green area» in terms of radiation safety. After a series of brainstorming sessions, programmers and circuit designers eventually solved this problem too.

** Swift (pronounced as [swɪft]) is a multi-paradigm object-oriented programming language created by Apple for iOS, OS X, watchOS and tvOS developers. Swift works with the Cocoa and Cocoa Touch frameworks and is compatible with the main Apple codebase written in Objective-C.

6. Testing on Android
One of the tasks of the DO-RA project in the field of visual event logging with geolocation support was «linking» the camera to allow the DO-RA Android app to take photos. The matter became more complicated by the fact that it was necessary to upload the user app not only to Google Play, but also to the Samsung Galaxy Store.

According to the app validation procedure, in the Samsung Galaxy Store, user software also had to be pre-validated and was only published after successful validation. At this stage, we had a lot of problems ensuring compatibility with various smartphone models purchased specially for testing the DO-RA software in the period when we were working on the Skolkovo grant. We had to dive into a huge box with up 100 devices—some of them powered by iOS, WP or TIZEN, some devices running on «antique» systems like Bada, Symbian or Java ME—and dig out the necessary devices running on Android.

Nevertheless, the majority of these devices were never sold in Russia (and some might never be sold beyond Korea). Some of them had only a frontal camera, and the app crashed when we tried to select another camera. Samsung provided access to a device pool for remote debugging, but we could not see anything when we switched on their cameras (maybe the devices were in cases or in a dark room).

In 2018, Google announced that new apps and updates to existing apps could be published in Google Play only if the app was built with targetSdkVersion 26 (Android 8). We had to urgently add app permission requests from users as well as update our service and notifications.

As a result, we solved all the main problems of the DO-RA project. Now we will wait for feedback from the people that use our devices in everyday life.

To be continued…
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