Everything Robotics…….and then some

Ok I have finally had a little bit of time to work on things (will be short lived as I’ve just bought a house and moving in the next couple of weeks Aghh!!).

Things are getting very close to reality after many design changes, the very nearly final Strobit Trigger base board, aka a modified Ardiuno BT board, with the Bluetooth removed and now fitted with the RFM12B SMD Tranceiver module and an external SMA antenna connector. The Eagle 3D side of things still needs work as some components are not shown and the inductor for the DC-DC converter is incorrect, but you get the basic idea right!

Why have I gone to a non-dedicated trigger board?

Well a couple of reasons, initially to cover myself from any patent issues that might have arrisen had I used a dedicated wireless triggering device, but mainly to allow better expandability. Why have a dedicated trigger with all the fruit and only use half of it, this way dedicated boards can be used, i.e. standard trigger, or sound/light trigger, sequences etc. Another reason is that the Ardruino is very well established and supported in the open source community, especially when it comes to the firmware libraries etc, it’s already been done. also I can use these in my robotics hobby as well, not just for photography.

Ok onto the board features:

• Fairly compact same size as ArduinoBT
• Standard Arduino Pin headers, so should be able to use with existing shields.
• Will operate from as low as 1.2V, so should work from x1 NIMH AA easily enough.
• RFM12 Tranceiver, up to 300m range (as per datasheets, although it does depend on the datarate)
• SMA connector so you can connect an external antenna for better reliability and range, or remove the SMA connector and use a piece of wire as the antenna.

What is left to do?

• Well the design is pretty well done, I want to get some prototypes made so I will be sending it off very shortly for fabrication.
• Different variations of shields need to be done, first one being stock standard strobe type of triggr, input and outputs, then others as needed

What did I say in my last entry about murphys law and my RFM12 header boards?  Guess what arrived in the post today lol…..

I couldn’t get any hands-on hardware development time for the Strobbit open triggr project today, so I designed a breakout board for the Sensirion SHT15 Humidity/Temperature sensor for my weather station I’ve been intending to build.  I have a couple of these sensors at home waiting for something this so I can have a play with them.  PCB uploaded for fabrication today.

As a side note:  While uploading this for fabrication at http://www.batchpcb.com  I noticed that my RFM12 PCBs has been panelized and so should be in production, hopefully they should rock up on the doorstep sometime soon.

The RFM12 module is a pain to prototype with due to the 2mm header (won’t fit into the breadboard), so I’ve whipped up a prototyping board that brings out the pins to a standard header.  It’s been it sent off for fabrication today so I should have back in the next week or so.   I’m trying out www.batchpcb.com for the first time so will be interested in how they turn out. 

In the meantime I’ve soldered on some wires but I don’t really like it.

I’ve put an initial design (both eagle source files and PDF) into SVN that is aimed as a board replacement to the ebay triggers.

http://svn.everythingrobotics.com/strobist/mk1/trunk/design/ebay_trigg.pdf

As i’ve started using Eagle as my electronic design package (protel is fantastic but just too expensive), I’ve created a component library that I’ll be using on the Strobe trigger project.  I’ve put the library in SVN for everyone to use and contribute towards -http://svn.everythingrobotics.com/strobist/eagleLib/