DIY Powerwall - Part 3

It feels like a very long time since I last posted about the powerwall! So where are you at? I hear you asking. I have two words for you. ‘Cell Fusing’. Yep, that’s right, I am still fusing individual cells. That’s 1400 cells, positive and negative. 2800 Spot welds on the most fiddly wire you can possibly imagine. Even if I complete one fuse every ~30 seconds it will still be 24hrs worth of fusing…..let that sink in a bit…

Saying that, it is not all ‘doom and gloom’, I have managed to make some progress on other fronts. The first is the cabinet shelves. I have managed to rig up some V-slot ally that I had lying around for shelves and was still able to use my vertical mounts on them. I also started work on some pack side protection and Longmon mounts. More info below!

EDIT: and yes I know the fuse wire is doubled up, It is easier to work with a continuous length. I am yet to trim them up.


Fusing - Lets have a quick chat about the path I took.

Very early on I decided to spot weld fuse wire on both the positive and negative sides of each individual cell. My reasoning behind this was that the cells are from unknown batches and even though I tested each cell individually I still did not trust each cell. It would have been a different story if I did not get the batteries from recycled laptop packs. The fuse copper wire I decided upon was around the 32AWG mark and is tinned with copper. This wire gave me about a 2amp draw before blowing. If an individual cell pulls 2 amp then I’m in a LOT of trouble anyhow.

It was pretty clear from the start that I needed to practice the spot welds. I grabbed a pack of 20 discharged batteries and went to town. The biggest thing I will say is that you do not need a lot of power when spot welding 32AWG tinned copper wire. I left the spot welder on 2 pulses and only put the power up to 5 or 6 on the dial. The other technique that needs practice is the positioning of the welder tips. You can either put both tips on the wire and weld or put one tip on the wire and one on the battery surface. Either or, does not really matter, however, I did notice at higher powers the welding tips would arc a lot more if putting both tips on the wire. You will find that the wire will break at the weld if under stress. Thus having two welds on the wire doesn’t really matter.


Cabinet Layout

My initial intent was to have the battery packs laid out vertically. I felt this was much easier on the eyes and for maintenance easier to get in and out. However, with the size of the cabinets and my battery pack sizes, I was not left for much room if I was to put two banks in. The cabinet was deep enough to run them horizontally and as it turns out uses the space much better. I still have a ton of room for more banks when/if required. Saying that I doubt I will be spot welding more packs any time soon. I still used the vertical mounts but laid them down and mounted to the V-slot. This will stop the packs moving if for some reason we have an earthquake or someone runs into the cabinet.


Cell pack side protection

This is a work in progress. Have you heard of the saying “Keep it simple stupid”? well, in this case, I am aiming VERY high and already feel that I will be coming back down to earth quicker than expected. Not only am I trying to protect the fusing on the side of the packs, but, I have also decided to incorporate the following items: Voltmeter, Cell Pack Labelling, Some Vents and a Longmon (BMS). I’ve decided to use 3mm clear acrylic and make a hybrid type case. I have attached a design file. It may change once I do the laser cutting. You will have to wait until part 4 to see how it turns out.

EDIT: 13/06/19 – Just in case anyone wanted to know how the first cut of the side protection covers came out. Check out the gallery below. It still requires some adjustments. I feel as if it has been over-engineered. But I will not really know until I try to mount the packs properly. Stay tuned.


Still to come:

  • Finish Fusing
  • Install Cable tray
  • Gland for Shed

  • Solar Install
  • Watchmon install
  • CB and Trip Install

  • A lot!

If you missed Parts 1 and 2 of the DIY powerwall. Here are some direct links:

Part 1

Part 2


Surframe V2 - Surfboard Photo Frame

It’s a Sunday…and it’s raining! So why not revisit one of the old projects and see if we could make some improvements! I’ve had these pine panel in the workshop for months and figured it was a good time to do some revisions. Every time I have made a photo frame like this the photo tends to get drowned out. So we went big! 12″ x 28″! That’s 304mm x 711mm for us metric minded people. Going that big had me playing with the size of the board and no doubt you can tell by the pics where I made the errors. Can you spot them?


CNC - The lazy man's router...

The CNC router has served me well. Even though I don’t really do a lot with it, it sure makes cutting 2D items super easy and quick. For this design, I decided to widen the board slightly so that the corners of where the photo and acrylic sit is a bit stronger. I was a bit worried that where the pine is laminated it could split apart. However, after cutting it seems to be pretty strong. The laminated panels I’m using are 450mm wide and somehow, as you can see I managed to cut outside the panel slightly. This was because I got a bit lazy and didn’t measure properly. (I also assumed my ‘zero’ reference points were wider than the cut…obviously not!)

Also, not sure if you have spotted it, but I had to use the ’tile’ function in my CAM software as the router is not long enough. This can be tricky, but having one straight edge is good to slide the panel through. This keeps everything aligned.


Manual Labour

I still have not figured out how to do a bevelled edge on my router, so against my will, I did this by hand. This gives the frame a bit more of that actual surfboard feel. It’s the little things that finish it off. Oh, I also sanded a whole lot. 250grit, 120 grit and even 1200 wet and dry to see if I could get that ultra smooth look.


okay, okay, so I made two frames...

As you may have noticed I did make two frames. The first was only 12″ x 18″. I felt the picture was drowned out a bit by the board, so I went to the larger format which I think will be a much better setup. The first frame I finished in a clear coat stain. I wanted to try and make the Pine ‘pop’. I am still undecided on this and will try some different stains over the next week or so. Anyhoo, I am sure you are sick of reading my babble so check out the progress pics below.


Look Dad, I dug a hole... (Movie: The Castle)

 


Do you Podcast? - Darknet Diaries

I have never really been a Podcast listener, however, in the last 6 months, one particular podcast caught my interest. This particular podcast titled “Darknet Diaries” was able to hold my interest for more than a few minutes. I am one of those kinds of people that flick through books really quickly and if I get bored, usually put it down and do not come back. (Hence why podcasts appeal to me!) However, this awesome production of geekiness and real-life stories easily quenches my thirst for topics I am very passionate about. The podcast is not so technical that you get scared away, it actually covers some great history and real-life examples of the hacking world and how vulnerable our digital lives actually are.

The Show is produced by Jack Rhysider and incredibly he is able to pump out two shows a month single-handedly! Jack also writes for a blog “Tunnels Up” which has a few cool bits and pieces that can be helpful. (Especially some of the cheatsheets… tunnelsup.com/cheatsheets/)

So, if you find yourself into similar interests, then head on over to darknetdiaries.com and get your fix ASAP. The episodes actually make your early morning commute and coffee bearable!

Latest episode on Spotify:

How can I listen?

Apple Podcasts
Google Podcasts
Youtube

How can I Listen?

RSS Feed
Spotify

I’m 100% sure Jack is always looking for new content to do podcasts on. If you think you have the right topic and some info to back it up, either leave a comment below and I will pass it on, or you can get in contact directly jack@darknetdiaries.com. Also, keep in touch with Jacks twitter account for updates and other pretty cool bits and pieces. https://twitter.com/darknetdiaries.

Personally, I just want to say a big thank you to Jack for the podcasts. I know it can take up a lot of time and I know the reward at the end of the day is minimal. But when I check Spotify and see that a new episode has come out it always puts a smile on my face. Cheers.


DIY Powerwall - Part 2

Finally some time for an UPDATE! The short story…I finally processed enough 18650 cells to start the build. For the long story, keep reading and check out the video. In this post, I am going to walk through some of the bits and pieces I have had to gather and sort out prior to starting the cabinet install. More often than not when undertaking a project like this, we never think about all the small details which must be taken care of prior to a build being completed. This is no different. As we know, lithium batteries, if not treated correctly, can be somewhat volatile, thus, some extra safety precautions need to be taken before bringing the batter online.


The Shed - No chance am I putting this build inside the house!

Having a suitable location for your powerwall is probably one of the largest considerations of the whole build. As mentioned earlier, if lithium batteries are not treated correctly it could end up in a molten mess and no matter how many fire extinguishers you have, the lithium battery fire will consume everything in its path. If you do not believe me, check out some of the videos on youtube! My build takes us out to the shed of course. The shed is not far enough away from my house for my liking, but have to work with what I have.

I was able to pickup this nice B&R electrical cabinet for $150. These cabinets are very sturdy and made from steel. The orange powder coasting was not by choice, but for the price, who am I to complain. The cabinet is large enough to fit my first 14S100P setup, with room to double it at a later date. (Top and Bottom) I am also looking to get some airflow top to bottom in the cabinet at some stage.

I went ahead and mounted some structural pine to the wall. My plan is to now use some slotted C-Channel to mount the inverter and components to the wall.. This will allow me to conceal some of the cabling, whilst maintaining the structural integrity of the ply and wall. I’m yet to decide if I should paint the ply….see what happens. I also need to look at cable management, and how/where to mount all the other associated equipment.

Insulation – As we are working from a common garden shed, I had to insulate the roof of the shed. It was getting WAY too hot inside to house all these components. I ended up purchasing some foam foilboard from the local hardware store and mounted a small 200mm solar vent. It seems to keep the temperature steady. Even on 40deg C days, it seems ok inside. I do plan to hook up some temp sensors into the future. Also some more ventilation. Bring in the cool air from the bottom, vent out the top.


Sorting and Stacking Packs

From what I have read, sorting your cells into equal packs can be crucial to the whole setup. The aim is to have the same (or very similar) capacity in each pack. But how do we do that? well, there are a couple of methods. The first and possibly most accurate is using some online software called “rePackr” which is located here. With this tool, the idea is you enter in the capacity of every single 18650 you have and it tells you which pack to put them in. Pretty much sorts them out so that each pack is as close to the same as possible. The downside is that you need to type in or cut and past in the value of every cell. When your wall contains over 1400 batteries this can become a PITA.

The method I chose to use was a bit more archaic but has been proven to get the job done. I sorted all the batteries out into groups of 50mAh. For example, the cells that are at a capacity of 2050mAh to 2100mAh would all be grouped together. I did this across the whole range of my cells. I think I ended up with 20 groups of cells. From here it was then pretty easy to take one from each group and fill the packs so that they were somewhat evenly mixed. The proof will be in the pack testing. Only then will I know how close I got.

Once we know the remaining capacity of a cell, we then write it on the side of the cell for future reference and we also notate the current voltage of the cell at the time. The cells are then placed into tubs grouped by capacity and left to sit for a minimum of one week. The reason for this is that we want to identify any cells that can not hold their voltage. These are known as “Self Dischargers” we do not want a cell in our packs that cannot hold a charge/voltage. This can have significant effects on our packs once built.


Battery Management and Safety

ok, so we have our packs now and we need a few additional bits of hardware to make sure out battery packs are as safe as we can make them. The first item used is a Battery Management System (BMS). The BMS we chose was the Batrium Watchmon setup. This seems to be the ‘go-to’ BMS for DIY type powerwalls at the moment. They seem to be doing a fair bit of development on the hardware and software which is always good. If you want to check out more of their items head over to the website here. In a nutshell, the Batrium BMS controls the charge states and the balancing of the packs. It is important to control this as we do not want to over/under charge the batteries and we also want each pack to drain and recharge in a balanced fashion.

The BMS works by connecting “Longmons” to each pack. These are small bits of hardware which link each pack together and provide the feedback to the Watchmon controller. The Longmons are the workers and do the balancing, monitor temps and a few other cool bits and pieces. The BMS, with the help of some relays, can also be used to trigger a shunt trip. The Shunt trip will basically cut off any use of the batteries during a fault state. For example, if the temp rises past a set parameter, the BMS can trigger the trip and all use of the batteries will be cut. This is just one of the safety features which I intend to implement.

In line with the circuit breaker, we also have some large fuse(s). These 160A HRC type fuses in a disconnect/isolator will also be used. At $12 per fuse and $50 for the holder, you can never have too much circuit protection. So not only will each of the individual batteries be fused, but the entire pack will also be covered.


So that’s it for part 2! Whats next:

  • Bus Bars on packs.
  • Cabinet Install
  • Solar Install
  • Lots of wiring up!

 


DIY Powerwall - Part 1

Why has the blog been so quiet I hear you ask…..Well…I started work on a DIY Powerwall from recycled laptop batteries. Yes, you heard correctly, I have started building a Tesla style power-wall from 18650 batteries. These are commonly found in Laptop battery packs. A why would I do such a thing, I hear you ask… In a nutshell, I want to save on electricity bills by using Solar a bit smarter and storing the energy for later use. I also wanted to see if it was possible to build a reliable/equivalent power-wall at a fraction of the cost of a Tesla style power-wall.

After a small bit of research, I stumbled across two resources that have become staples in my DIY Powerwall diet. Those are the “Second Life Storage” forum and the “HBpowerwall” Youtube channel, run by Peter Matthews. Using these two resources you can find out just about everything you need to know about building your own power-wall. Check out the links. Also, check out my journey below.


First Steps - Find Laptop Packs, Pull them apart...

Some of the DIY’ers find this step one of the most difficult. Finding laptop battery packs to recycle the 18650 cells from can be tricky. I approached a few battery stores and computer stores but most seemed disinterested in selling me the old packs. I am not sure if it’s a health and safety thing, or they get more recycling them. However, after finding the right people through a few Facebook groups I was able to get a steady supply of laptop batteries through an IT recycler. At first, I purchased 20Kgs of batteries not knowing what I would get. But then went on to purchase 30kgs, 40kg and most recently 60kgs. The break-down of how many usable cells I actually got from these old laptop batteries is below.

Everyone has their own method for pulling apart the laptop packs, however, I will say that safety is paramount here. The last thing you want to do is slice yourself open on the nickel strip or even worse short/explode a cell or two. (Saying that, it’s pretty hard to do this unless you’re super careless.)

I would suggest purchasing the following items:

  • Vice Grips
  • Sharp Small Side Cutters
  • Gloves
  • Eye protection

The end state of pulling the laptop batteries apart is to get the singular 18650 batteries out. Once we have them out and ready to go we can begin to analyse them to see if they are suitable for our powerwall. Noting that these batteries did come from old laptop batteries we really do not know what state they are in, we must “process” the cells to determine the capacity of every cell. Also, try and detect the bad from the good cells.


Step two - process a heap of cells

Once you have started your journey to building a DIY powerwall, you will no doubt need to process bulk cells to weed out the good from the bad. There are many ways to achieve this outcome, however, I will give you a rundown on how I am doing it. (And a basic guide to budget required for processing.) This part is easily the most tedious part of the build. For example, if you decide you would like a 48v 10-12kwh powerwall then you are looking at requiring 1400 cells at a minimum. 1400 may not sound like many, however, after weeding out the bad cells, you soon find that it does take time.

The process that I follow to process cells is as follows. First I will check the voltage of each cell. If a cell pulled directly from a laptop pack is at 2V then it will go into the pile to be charged/discharged via the charge wall. If the cell is below two volts then I will put the cell into another pile which will require a specific charger to get them back to health (If they can be revived…)

For the cells that pass the 2v test, they will then be placed into the cell holders attached to the TP-4056 chargers. These small lithium specific chargers are very cheap and an ideal way to bring any old batteries up to full charge. You can pick these up from eBay very cheap in packs of 10-20. I went with 20.

Once the cells are charged to maximum voltage, the cells are then cycled into the Opus chargers for a discharge test. This is will give us the remaining capacity of the cells. Basically, it ensures that the cell is at 4.20v, discharges the battery to 3v, records the capacity in milliampere hours (mAh), then charges the battery back up to 4.20v ready for the next test.

Once we know the remaining capacity of a cell, we then write it on the side of the cell for future reference and we also notate the current voltage of the cell at the time. The cells are then placed into tubs grouped by capacity and left to sit for a minimum of one week. The reason for this is that we want to identify any cells that can not hold their voltage. These are known as “Self Dischargers” we do not want a cell in our packs that cannot hold a charge/voltage. This can have significant effects on our packs once built.


Step three - prepare processed cells for packs

It will depend on a lot of factors how you will proceed with building your packs. Each choice will have pro’s and con’s. Go with the method that best suits your cell count and abilities. At present, I have not 100% decided on the method I am going to use, however, I am re-wrapping the vast majority of my cells first. Once I have 1400 quality cells, I will then arrange them into 14 packs of 100 cells. (14S100P) This will give me a 48v nominal power-wall around the 10-12kWh.

So where am I at right now… Well I have processed approximately 60Kgs of recycled laptop batteries. I set my limits for the cells to go into my wall at 2000mAh. I currently have 4 packs with 100 cells in each pack. If I lower my standards to 1800mAh I could probably have a 5th pack built, but for now, I plan to stick to the magic 2000mAh in capacity for my wall.


Once I move onto the next phase of this build, I’ll post Part 2. The next post will cover off on some of the following bits and pieces:

  • Cell pack builds (Once I decide which method to use)
  • Some tips and tricks for better pack build.
  • Solar/Inverter installation and connection to battery packs.
  • cost/cell breakdown
  • Anything else I can think of that may be relevant! (Let me know in the comments what you want to know?!)


Raspberry Pi TV server using TVheadend

I have a projector out in the theatre room, however, this same room does not have any coax run for TV reception. Nor does the projector have a tuner for Digital TV. Thus the idea for the RPi TV streamer! I could have easily gone to the local tech shop and purchased a tuner and ran some coax, but I already have an android device hooked up to the projector, why not try and stream TV to it locally in the house. My own IPTV service of sorts.

I do want to give a bit of a shout out to CWNE88, (Go follow him if you get a chance!) This is the guy that got me started streaming TV via the Raspberry Pi, however he concentrates a lot on multicast streaming and to be honest, most of us do not have the infrastructure to handle multicast traffic on our LAN. So I had to find an alternative option that actually worked. (dvblast works great…if you have suitable switches/routers to handle multicast) Anyhow, during my research, I stumbled across TVheadend. I learned pretty quickly that it could be installed on a Raspberry Pi and be used to stream tv via HTSP. (Home TV Streaming Protocol) HTSP is a TCP based protocol and works in a unicast type fashion without killing your home network.


This is the hardware you will require:

  • Raspberry Pi 3 B+ (This is what we tested with)
  • USB Extension Cables
  • Good quality 5v power supply for RPi
  • USB TV Tuner (We used Avermedia Volar Green HD @ $29ea)
  • Splitter (We used a 3-way splitter to really push the RPi3B+)
  • F-type adapters
  • USB to Ethernet Adapter (Optional)


Prerequisites

I am going to assume you know how to get Raspbian “Stretch” Lite onto your Raspberry Pi. If not check out the “Prerequisites” of this post here. It will walk you through, downloading the image, using Etcher to put the image onto an SD card, setting up the RPi via Raspi-config, and enabling SSH. Once you have completed those steps, come back here and continue.

The end state of the “Prerequisites” is to have access to your Raspberry Pi via SSH and have the command line up and in front of you.


For those confident on the RPi

For those of you who want to skip straight to the chase, the code below outlines all the commands issued to the RPi to install TVheadend. I will then take you step by step through these commands below:


Step 1: Update/Upgrade the Raspberry Pi

First things first, you need to ensure your Raspbian repositories are up to date. Run the Following commands:

sudo apt-get update

sudo apt-get upgrade
Select ‘Y’ and go get a coffee. This process can take 5-10 minutes.


Step 2: Install TVheadend server

Now that your Raspberry Pi is fully up to date, you need to run the following commands:

sudo apt-get install dirmngr

This command may not need to be run, however, for me, TVheadend would not install without it.

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 379CE192D401AB61

More info about installing the GPG keys can be found here.

echo "deb https://dl.bintray.com/mpmc/deb raspbianstretch stable-4.2" | sudo tee /etc/apt/sources.list.d/tvheadend.list

Again, more info on where to get the correct repo for the RPi ishere.
Check and make sure the correct one is used. This can update at times.

sudo apt-get update

In a nut-shell, we are telling ‘apt-get’ to grab any updates from the repository we added above. This will then allow us to install TVheadend because it now knows where to ‘grab’ it from.

sudo apt-get update

In a nut-shell, we are telling ‘apt-get’ to grab any updates from the repository we added above. This will then allow us to install TVheadend because it now knows where to ‘grab’ it from.

sudo apt-get install tvheadend

Select ‘Y’ and allow TVheadend to install. If you tried to run this command without doing the steps above, you would run into errors.

During the install, you will be asked to set an administrator username and password. Be sure to set this correctly and remember. You do not get two chances to enter the password. I learned this the hard way!

If for some reason, you did stuff up the username and password. Uninstall tvheadend with sudo apt-get purge tvheadend and sudo apt-get autoremove Then reinstall tvheadend again.


Step 3: Log into TVheadend

Now that your Raspberry Pi is fully up to date, you need to run the following commands:

Open up a web browser and enter the IP address of your Raspberry Pi. Also, use the port number ‘9981’. For example http://192.168.1.168:9981 (Your IP address for the RPi will be different.) Type ifconfig in the terminal screen to confirm.

When you first open Tvheadend, you will get the Wizard which will step you through setting up the tv tuners. Hopefully, you left them plugged in from the start. If not, plug them in and restart the Raspberry Pi. Go back into the web browser and log back into TVheadend.


Step 4: Configure TVheadend for streaming

The configuration for TVheadend settings post is here.

I have no doubt, however, if you got this far, you will be able to bumble your way through the configuration. This was the easiest part. I then used VLC to watch the streams. You can get these links from inside Tvheadend.

If you want to consume some TV from your iOS device, I can confirm that the tvhclient app works a treat. No nonsense setup, easy channel browsing. It can be used in conjunction with the VLC app to stream video easily.



Video: Example Hardware Configuration


A Brief History of the Raspberry Pi

Who would have thought a US$35 computer would change our lives so much. The Raspberry Pi foundation have changed the way we learn, teach and innovate by bringing a hardware platform which is cheap enough for the ‘average joe’ yet powerful enough to drive some of our most ambitious ideas. I have no doubt in my mind that I have left some info out here. Please feel free to leave a comment below to educate me a little bit! happy for input. I’ll keep updating this timeline as new releases come out. Thanks.



Some additional credits for the pics and info: Adafruit.com, Raspberry Pi Foundation, elinux.org

Who would have thought a US$35 computer would change our lives so much. The Raspberry Pi foundation have changed the way we learn, teach and innovate by bringing a hardware platform which is cheap enough for the ‘average joe’ yet powerful enough to drive some of our most ambitious ideas. I have no doubt in my mind that I have left some info out here. Please feel free to leave a comment below to educate me a little bit! happy for input. I’ll keep updating this timeline as new releases come out. Thanks.


The Alpha Boards

Announced in August 2011, the ‘Alpha’ boards were among the first revisions. The Board itself was of a large format for debugging, was populated with headers for GPIO, JTAG, DSI, CSI and switches for LED and I/O testing.


Raspberry Pi First Production Board

Announced in 29th February 2012, The first of the “credit-card” sized computers was released. The initial batch of 10,000 (All Model-B’s) which were manufactured in China.


Raspberry Pi Model B

The RPi full production board – Model B Rev 2.0 was announced in April 2012, first orders were not sent out until June 2012. Manufacturing and orders were made via RS and Farnell. This meant that higher volumes of units were produced and made available. September 2012 saw the announcement of Model B rev 2.0 also being manufactured by Sony.


Raspberry Pi Model A

As of February 2013, the Model A was made available from distributors in Europe. The board had 256MB of RAM rather than the originally planned 128MB. The RPI foundation produced a small Beta batch of boards before handing over manufacturing to RS and Farnell. The Model A boards use an identical Rev 2.0 PCB but come with a different selection of components fitted.


Raspberry Pi Model B+

Announced on the 14th July 2014 The Model B+ was the first of the new layout. The B+ featured a new and faster processor, new VideoCore, 512MB RAM, Micro SD, 4 x USB slots, HDMI and many other upgrades.


Raspberry Pi Model A+

A few months after the release of the B+, the RPi foundation released a lower-cost variant labeled ‘A+’, At a new low price point of US$20 it was a smaller form and only a few components had been left out. But from an IoT perspective, it was still a very powerful unit for embedded hardware projects.


Raspberry Pi 2 Model B

Announced n 2nd February 2015. The RPi 2 Model B+ retained the same US$35 which was key to the continued success of the platform. The RPi 2 featured another upgrade to the CPU and an upgrade to 1GB of RAM. Other changes were also made.


Raspberry Pi Zero

The Raspberry Pi Zero was released in November 2015. The idea behind the Zero was a cheaper/smaller form factor that could be used to embed inside smaller projects. On 28th February 2017, the foundation then released the RPi Zer ‘W’ which had built-in wireless and Bluetooth.


Raspberry Pi 3 Model B

Another upgrade to the CPU (1.2Ghz 64-bit quad-core ARM Cortex-A53) was announced with a new release of the RPi 3 Model B on the 29th February 2016. Again the Raspberry Pi foundation achieved the same US$35 price point.


Raspberry Pi 3 Model B+

Announced in “Pi Day”, 14th March 2018. The Raspberry Pi 3 Model B+ is an incremental improvement over the previous RPi 3 for the same US$35 price.


Some additional credits for the pics and info: Adafruit.com, Raspberry Pi Foundation, elinux.org


Inspecto Roboto: A dirty robot, just how we like it.

Our resident electronics expert, Andrew has been busy in the man cave this weekend. After reporting some dampness inside his house he decided to take matters into his own hands. The outcome: ‘Inspecto Roboto’! Andrew has pulled apart his racing drone and a few other bits and pieces to hack together a pretty sweet inspection robot for under the house. Check out his build below. And don’t forget to check out some of his other cool projects on his website.

 

Check out the Video in HD here.


Some of the Key components

  • Lynx motion Tri-Tracks chassis
  • 2 x 12V geared DC motors
  • LM298 motor controller drivers

  • 4s LiPo battery pack
  • LED light bar
  • Servos

  • Taranis hobby RC transmitter
  • FRsky receiver
  • Teensy 3.2



The 'Inspecto Roboto' - A confined space inspection robot.

My house has a bit of a moisture problem and I wanted to inspect the floor crawl space to see if there was an obvious fault. It is a horrible cramped environment that whilst I can just wiggle inside the rat carcass at the door confirmed my doubts about venturing any further. So I decided to tackle the problem with robotics!

This was a weekend build and whilst I just used parts lying around I had a lot of nice spares and old projects to work with. Essentially this was a hybrid system using parts from an old racing drone & a lynx motion robotics kit.

Locomotion was a lynx motion Tri-Tracks chassis. It has a nice set of rubberized Tracks as well as an acrylic frame, two 12V geared DC motors and other associated hardware. A basic LM298 motor controller drives each set of tracks from a 4s LiPo battery pack tucked inside. The camera system was from an old racing drone with an FPV display to make driving it around easier. The servo allows for tilting the camera up, panning is just turning the robot on the spot. Finally, a large LED light bar from a vehicle was installed up against the front with some additional acrylic pieces to act as bushes and help retain it in place. The light is controlled via a relay as it is convenient to switch it off when unrequired as it draws about 12W.

The controller was a Taranis hobby RC transmitter paired with an FRsky receiver and a teensy 3.2. The teensy decodes the signals & operates the motors, lights & servo. I have written about using these transmitters with microcontrollers before (Here) and they are a great option for long-range and reliable communication which xBees & other serial radios often struggle with.

The whole system was a bit of a hack but as someone who often spends forever ‘gilding the lily’ on a project until they grow bored of it and don’t finish it, this was a fun and pleasant change.


Andrew Van Dam

An electronics expert based in Australia dedicated to creating great tools for the maker community.


Controlling GPIO with your travel router

The GL-inet range of travel routers are sold with the understanding that we can use them as more than just a router. The idea of being able to interconnect them with everyday items is very appealing. They call this the ‘internet of things’. So the curiosity got the better of me and decided to see if we could do the most basic of tasks. Switch a relay module!

Sounds simple, and sure enough, once we did a bit of research, it was. Keep reading to find out the basics of setting up your GL router to trigger a relay module using the built-in GPIO pins. If the config stuff is a bit boring for you, skip directly to the working video below!


Some light reading/research

  • http://wiki.openwrt.org/doc/hardware/port.gpio (Understand how OpenWrt and GPIO works)
  • You will require a GL-inet router. We used a GL-MiFi and a GL-AR150
  • You will also require a 5V relay and some headers/jumpers to connect
  • A soldering iron


Pinouts (For reference)


Solder some header pins to your device

First of all, you will need to decide which what sort of relay you are going to use and which pins to utilize. I only had 5V relay spare, thus I need to grab 5v from the board and a signal from a GPIO pin. Connect the 5V + and GND up and the signal/GPIO.

The gallery above has the pinouts for the GL-MiFi and the AR-150. Check these to determine the pins you want to use.


Add some config to the router

SSH into your router, locate the file: /etc/rc.local – Add the config below. Remember to set the pin number to the GPIO you intend to use. This will enable ‘output’ on that particular GPIO. Also, make sure you insert before ‘exit 0’


Add some config to the router

Shutdown your router. Connect up your relay to the 5V source, and the GPIO you selected in the rc.local config. Power back on your router, SSH back in and run the commands below. “1” will turn the relay on, and “0” should change the state so that it is off.



REVIEW: GL-MiFi 4G Smart Travel Router

If like me, you travel a lot, then having a solid travel router that allows me to work on the move securely and with anonymity is a necessity. The GL-MiFi router has proven to be a solid and reliable unit that has some perks that other travel routers cannot match. This review will cover some of the pros and cons. However, saying that, the Pros far outweigh the cons!

The GL-MiFi is powered by an Atheros AR9331 processor, is small, lightweight and contains a slot for various PCIe 3G or 4G modules. Combine that with 150Mbps Wi-Fi and you have yourself a very powerful little device. The GL-Mifi runs an embedded OpenWrt system, is extremely extendable via hardware and software. It can be used in mobile applications, industrial, commercial or at home.


Pros

  • 3G/4G capable
  • Built in Battery for mobile use
  • OpenVPN client capable
  • Excellent portability
  • 6-8hrs uptime on battery

Cons

  • When trying to charge the battery, router turns on.
  • GL-inet frontend software can be clunky at times.
  • Sim card can easily be inserted incorrectly.



Specifications

CPU Atheros AR9331, @400MHz
Memory DDR 64MB/ FLASH 16MB
Interfaces 1 WAN, 1LAN, 1 USB2.0, 1 micro USB (power), SIM card slot, MicroSD card slot, Antenna SMA mount holes
Frequency 2.4GHz
Transmission rate 150Mbps
Tx power (maximum) 18dBm
Protocol 802.11 b/g/n
Power supply5V/2A
Power consumption <3W
Dimension, Weight105*72*27mm, 170g


The Hardware

When you first get your hands on the router, you notice that the enclosure is very solid. (As you can tell, I have dropped this unit twice… and it still works!) Nothing about the physical form of this router says “cheap” or “made in China”, The quality is second to none. All clips, buttons, and panels feel as if they will last the distance. This gives me confidence, I was certainly not afraid to throw it in my backpack with all the other crap I carry around.


3G/4G Module(s)

One of the standout inclusions in this travel router is the modulized 3G/4G PCIe cards that can be included. We ordered the Quectel EC25-AU with the unit. The seamless integration of this module with the built-in WiFi means that we can share a 3G/4G connection with as many devices as we need to. The configuration is as easy as inserting a sim card and selecting the region and provider. The module connects very quickly, so long as you have a data plan you will have connectivity to the internet. Of all the GL-inet travel routers the GL-MiFi is the only one with integrated cellular. Sure the other travel routers can use a USB dongle and tether, but nothing beats the quality and reliability of these built-in modules. For more info on the Quectel 3G/4G modules check them out here.


The Software

The GL-MiFi runs an OpenWrt firmware with a custom front-end user interface for its users. I think the ‘vastness’ of the LuCi interface could be a bit daunting for some, so they decided to write a front-end graphical user interface (GUI) that is easier to use and understand. From a basic user point of view, I think they achieved this goal. However some of the more advanced tasks you still need to achieve from the LuCi interface.

The custom interface interacts with OpenWrt and at times can feel a little bit clunky. Firmware improvements are being rolled out all the time and in the few months I have had the unit, I can see that the GL-inet crew are developing this frontend and fixing bugs as they come up.


The Fun Stuff

By Far the coolest part of the GL-inet routers is the fact that they can operate as an OpenVPN client and a Tor router. (We will do a post soon on setting up as a Tor router.) However, for now, we are going to focus on the OpenVPN side of the device. The OpenVPN client can be used in two ways. Either connect to your own self-hosted VPN server or connect to one of the popular paid VPN services. The paid services allowing anonymity and safety of your data whilst traveling, or operate through your own self-hosted VPN for access back into your business or home network. A typical setup of the OpenVPN service through a paid provider can be found here. (The setup on this router is the same for the MiFi)

If you have a keen eye on the GL-inet routers then you might have also seen in the newest firmware an ‘OpenVPN server’ being rolled out in beta form. I am yet to have a play with this, however, it is exciting to see a device no bigger than a rich-mans wallet hosting its own VPN server.


What next?

So many cool things still yet to be achieved with this router. Here is my list, in no particular order, of the bits and pieces I want to achieve.

  • Solar power kit to run the MiFi indefinitely.
  • Run up the Tor firmware.
  • Look at Mesh firmware
  • 3G/4G VPN tunnels into other networks
  • Control relays from GPIO pins onboard.

If you have any thoughts on what else we could do here, let us know in the comments below. Very keen to get your thoughts!!!