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  • Author Author: balearicdynamics
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Meditech: Starting over

balearicdynamics

Introduction

The Meditech project is moved to the further step 1. This will produce the formerly testing version of the device; this means a version enabled for testing with volunteers. To move the project and the prototype to the end of this step a series of essential upgrades has been focused playing on the actual version. While Meditech phase zero aimed to reach a full working prototype, despite of the aspect the testing version Meditech phase 1 will be the first full working prototype.

 

This introduction post points out the first series of changes that will be applied to the actual running prototype to set it as perfectly working in a test environment. Further improvements will be added to the internal architecture and the software component; the release date for the Phase 1 prototype version is expected around the mid - end of the month of October.

 

Display

The actual prototyped display was 15 inches so an external support was needed. The main issue of this display is its weight and the portability: the device and be easily put in-place but an extra transport bag is needed to carry it and this will reduce the usability of the system that should be set in the normal working conditions in a very short time.

imageimage

How the display actuallly fits and the back support.

 

The obvious solution mentioned in the posts related to the screen is a smaller 10" or 7" screen that will fit well hosted in the middle of the Meditech device when it is closed. The following image shows the free space for the display that is about 40x20 cm. A custom support should be created supporting the mechanics to slide it in the usage position.

image

 

The newly announced <strong>7" touch screen for Raspberry PI</strong><strong>7" touch screen for Raspberry PI</strong> maybe a good solution also for the good price it is proposed on the market.

 

Control panel cover

In the first version of the prototype the control panel cover has been done with two half of soft 2mm plastic material. The following image shows how it is now; this simplified a lot the disposition of the components on the surface (the GPS and a couple of jack plugs are always missed in the image) as it is very simple to drill and cut.

image

 

Then next version will be precisely cut and milled on a 1mm white Aluminium plate; the material is shown in the image below. This solve also the problem of labelling the plugs and signals: a full adhesive surface will be done and applied with the same material used to put the advertising images on the car surface. With the size of the surface this solution will be efficient at a very low cost (about 3-5 Euro)

image

 

Cabling

As show in the following image the actual version is using common commercial cables that result very longer than needed. A series of custom cables will be wired saving a lot of space. Also the power distribution will be affected with a better single board circuit and all where it is possible the round cables will be replaced by flat ones.

image

 

Internal devices and components

Also for the internal devices a strong revision will be provided.

image

  • Make more reliable supports for the Raspberry PI Devices
  • Single-board including all the control panel components (fan control, IR controller, LCD, LEDs
  • Rationalise the power supply, powering the Raspberry PI via the GPIO connector instead the mini USB  plugs
  • Use flat cables all where is possible
  • Optimise the network cabling
  • Improve the door-open switch
  • in reply to saturnv

    Forgot a not about the screen. As I wrote in the post, the screen will be reduced just to fit is inside the system.

     

    If you read the previous posts I wrote on this project, the device should be as much portable as possible so the use of the reduced screen is just for the better usability and make it portable. No way to mount it outside the case just for the portability reason.

     

    Enrico

  • in reply to saturnv

    Hi Michael,

     

    good news to know your cabling knowledge image The use of the flat cables is limited (will be) just to the short connections, i.e. between the ChipKit PI and its own Raspberry PI all on the same side and few cm, the LCD vs the control pane (placed just to the bottom of the LCD, other few cm) and the GPS unit that is on top of the Raspberry PI that uses it. All the other cables are shielded including the final trunk of the power distribution (i.e. from the center to the Raspberry PI devices.

     

    The rebuilding of the control panel circuit board (that was grown step by step before) in a single circuit will save risky cabling. So you suggestions will be very useful. Hope you continue following the next posts image

     

    Enrico

  • in reply to jw0752

    Hi John,

     

    the stability of the connection until now has not been involved. It is also because the most risky was the internal LAN connection but it has shielded cables. Anyway these cables should be shortened just for a practical question of space. The use of shielded cables and the 100Mb only network (that is more than sufficient for the internal traffic of the device) may help and definitely eliminate the risk of the signal bleed. At the moment the only non-shielded wires are the power lines and the flat cables that are kept as short as possible.

     

    Enrico

  • in reply to DAB

    Hi DAB,

     

    this is almost the idea. But the control panel can't keep all the things on one side only without penalising the usability of the probes; take in account that some of them maybe used together. Anyway most of the parts sure will be put in one corner with a reasonable distance (about 5-10 cm) from the power cables.

     

    Enrico

  • Hi Enrico,

     

    Among other things, I'm kind of a 'cable guy'.  Dressing cables is a pet peeve of mine over the years. One of the nice things about todays ribbon cables is that they lay FLAT. So if you place your electronics and modules in such a way that your cabling, (preferably ribbon cables), will lay flat, you run all your cable from the bottom of your case to the top along the same plane as your hinges of the Medtech case. Some placement, or rebuilding of some circuit boards would definitely consolidate and save space, but probably not a major concern at this stage of the project.  Have you considered a smaller screen, or enclose the Medtech in a dual case where the screen is mounted on the outside of the case, yet has a protective cover over it for transporting?

     

    Good luck!