SPABRINK Project concluded succesfully
Main objective of the SPABRINK project was to develop a new type of outdoor advertising tool where the image can be changed remotely operated through the internet. The system uses ink powder with electrostatic properties so it can be used for printing onto a flexible foil. Together with a wiping technology the powder can be collected and reused. The aim was to develop a 2 m2 prototype during this project and validate it in real outdoor conditions. This main objective was accomplished by the end of the project (31 August 2015). A functional prototype was developed and successfully tested in relevant environment.
The project started on the 1st of September 2013 with carrying out a market survey, an in-depth component search and requirement analysis. The gained experience and the additional inputs provided by the consortium SMEs resulted in system specification.
The overall design specification has determined the main modules needed for proper operation:
- selection of a proper colour model
- definition of a suitable powder attachment technology
- determination of optimal powder deposition
- selection of the most suitable powder removal and separation method;
- definition of the control system and the auxiliary parts including the mechanical parts and the monitoring unit.
The Scientific objectives were in line with the defined tasks:
“To develop a new colour scheme in order to display good quality images using glass powder.
Due to the powder properties neither the subtractive (CYMK) nor the additive (RGB) way of creating images is possible. Therefore a new method has to be developed with as little amount of colours as possible.” and
“To create a knowledge base of the existing products and technologies facilitating the enhancement of the SPABRINK system in order to make it more affordable.”
The technical development started in three research and development areas in parallel: the colour model, the printer technology development and the adhesion to foil issues.
The colour model related scientific objective was achieved by developing a colour mixing scheme suitable for the SPABRINK system. Extensive experimentation and simulation have been performed and based on the results the consortium concluded to use the 7 colour RGBCMYK scheme with 4 brightness levels.
The “printing” or “powder depositing” development had several technology related objectives:
One of the most important issues were relating to the proper paint powder selection:
“The exact material of the ink powder that can be easily deposited and have good colour properties”
To achieve this goal several inorganic and organic materials analysed and tested by CERC and evaluated by the Consortium based on several technical aspects. The objective was successfully achieved by selecting a material having superior colour properties, inexpensive and shows good behaviour in terms of printability and separability.
The printer head related objective was to develop the powder spraying system for the different sized powders allowing perfect deposition rate and reliability.
At first a Digitally Controlled Powder Dispenser unit was developed to prove the working principle of the controlled way of solid particles deposition. Several technical problems were solved and also life-cycle and long term reliability tests were performed. A small scale printer was built with control electronics in the first period of the project for testing purposes.
The final printer head design was completed and documented with the finalization of the powder selection. The printer head driver was developed together with the SPABRINK control system. The powder spraying system with 7 dispensers became fully operational when it was integrated with control unit, communication module and the monitoring system into SPABRINK prototype.
Another crucial research and development area was to solve the powder adhesion to foil and the right printing foil selection.
Results gained from electrostatic development led to a method, where the powder adhesion can be fully controlled by applying high voltage to the electrodes on the substrate. Powder remains on the foil as long as the voltage is applied, and most of the powder can be removed by de-energization. Temperature and humidity hardly has any effect on adhesion force while negligible powder was lost within the planned foil displacement range, showing surprisingly strong adhesion. The selected laminated foil structure is flexible enough to allow the required bending radius while providing proper mechanical strength.
The final powder sticking technology was successfully developed and these objectives were fully achieved.
Having completed the development of the colour model, the printer technology with selected powder and the adhesion with laminated foil design, the team continued their project with the mechanical and electrical realization, including software development.
The technology related expectations included mechanical design of the integrated prototype :
To develop a mechanical system that houses the powder deposition (printing) module, the roll-able printing surface and powder collecting system. T
“To develop a colour separation methodology and if technical and economically feasible develop it so it can be included in the SPABRINK housing.
The core mechanical structure was built from extruded aluminium profiles with standard joints to allow the necessary flexibility required by prototype building. The outer cover, the front door and the back doors were made by bended and welded sheet metal with rubber sealing. The front door equipped with Plexiglas window for good visibility of the printed foil. The mechanical unit includes a novel foil forwarding roller system and paint powder removal mechanism to clean the canvas. The completed prototype integrated powder refilling unit, used powder collecting tray, the printer and the control units as well.
Powder separation technique was developed and implemented based on magnetic separation and sieving. The mix of powder is first separated into two main fraction using the magnetic properties followed by mechanical sieving. A novel rotating drum-sieve mechanism was developed. Based on financial aspects and calculations, Consortium lived with the opportunity not to integrate the separation unit for the time being.
Series of Technological objectives set targets for the control system, hardware and software development tasks:
“To develop a control system that can convert any image into the SPABRINK colour format and can control the printing.
“To develop a low cost wireless communication unit that allows the remote control of SPABRINK.
“To develop visual monitoring so the user can see actual display remotely. “To develop a user-friendly software for uploading new images. The software will be able to recognise the shape and size of the board and process the uploaded image accordingly in real time
The image processing unit and the control system was developed accordingly with all image processing and printing functionality. Although the image conversion time is highly dependent on the image size, the conversion time is less than 60 minutes. The printing time is about 4 hours for a fully saturated image.
The communication module was developed. The system uses standard 3G modem that can be purchased for less than 10 Euros, providing both 3G and 2G connectivity. During and after the integration the wireless communication was tested and evaluated.
The image processing component and a configuration tool software module were successfully designed and developed. The distorted images are corrected within 10 seconds. The monitoring component was tested with the integrated system and was found capable of processing recorded images of onsite printed advertisements.
A web-based user interface was developed. The software allows remote monitoring of all the connected SPABRINK endpoints simultaneously and advert printing can be initiated. The software was tested on the integrated hardware in laboratory and real environment.
Having achieved the Scientific and technological objectives, the SPABRINK prototype became ready for testing and evaluation:
“To build a 2 m2 prototype and test it in real outdoor environments through the end users of the consortium. The image quality will be measured against existing technologies using the subjective opinion of experts from the media industry.”
The SPABRINK prototype design was finalized and materialized. There were laboratory and out-door testing. The image quality was assessed by the Consortium during and after the laboratory tests. The printouts were compared with existing technologies. Consortium members and external media experts found the image quality satisfactory. The most suitable creative types and application areas were defined, where can be competitive to the existing technologies.
The patent was already submitted. Since the end of the project, there are ongoing negotiations with big media outdoor players to further develop the prototype and to have a final product.