Potential new venue

We have some very exciting news. A few of the members have been scoping out new venues, one in particular looks very interesting. The next meeting on Thursday 11th February will be held at this venue.

So please note

The next meeting will not be at the usual venue. We will be meeting at 83 Grimwade Street, Ipswich.

Parking is available in the UCS car park near the Waterfront, free from 6pm. If you are bringing something large or a lot of stuff then post here or on Facebook as you may be able to park by the property briefly and unload.

This meeting will be opening at 6pm to allow for extra setup time and scoping out that may required. This is not confirmed as a new home yet, so keep an eye on Facebook and the website for the locations of future meetings to ensure you turn up at the right door. We shall endevour to give you as much notice as possible.

Grimwade Street is a busy road, so park up in the UCS car park and walk round. You are looking for this building hiding behind the trees.

We have a robot

Just a quick post, last night was quite a moment for us. This week Keith and Phil have been working on the laser cut files and they have now been put together and we actually have a robot. TractorBot 2015 has left the virtual world and now actually exists in reality.

The almost completed robot

Also going on this week, Jon has been working with the Hall Effect sensors and has created a library so the Pi can read the sensors via an Arduino Pro Mini clone. Along with this he has also been working on some PID (proportional, integral, derivative) code to allow TractorBot to drive in a straight line along with navigating the three point turn course. Jon just needs to tune it now so that it works with the competition bot seen above.

Phil has been fine tuning the line following code, but once again this really needs to be tuned on the competition robot.

Things that still need to happen. The robot has not moved yet, we are awaiting delivery of a couple of PCB’s, one to mount the line follow sensors and the second is the main interface board which hooks everything together. Hopefully these will be arriving today and maybe tonight TractorBot will move!

Keith also needs to convert the trial skittles ball launcher to fit the new robot and get the bits laser cut by Phil, the wire holder for the Pi Noon challenge needs to be designed and 3D printed, as do the wheel hub magnet mounts. Lots to do, now where is that Red Bull!

Cheap Raspberry Pi Robotics Kit – EduKit 3

If anyone is looking for a cheap way to get into robotics with the Raspberry Pi, you cannot go far wrong with the CamJam EduKit 3 Robotics Kit. It comes with everything you need to create a Raspberry Pi robot, you just need to add your own Raspberry Pi, any model will do, and batteries. Oh, they don’t provide a chassis either, but that can be made from anything like an ice cream tub to a piece of thick cardboard or even the box the kit comes in.

Not only is the price of £17 brilliant, the CamJam team have also provided a series of worksheets which take you from Introduction, through building the robot and then onto using the sensors and creating a line following and other robot operations. This is a great educational tool and would make a great Christmas present for kids or adults alike.

The kit consits of the following:

  • A custom-designed, pre-soldered motor controller board (with screw terminals)
  • Two DC motors (with wires pre-soldered)
  • Two custom red wheels (which go extra fast… because they’re red!)
  • A ball castor (used as the ‘third wheel’ to your robot)
  • A small breadboard (to create your circuits)
  • Two pieces of strong 3M padded double-sided tape
  • A battery box for 4 AA batteries (batteries not included)
  • An ultrasonic distance sensor (for detecting objects in front of your robot)
  • A line follower sensor (for detecting and following black lines)
  • Resistors and jumper cables with which to complete your circuits
  • A strong cardboard box to keep it all in… or to cut into to make your chassis!

This kit is highly recommended and as a bonus, soldering is not required, it’s all plug, code, play.

If robotics seems a bit complicated for now, the CamJam team also offer two other great EduKits with sensors and more work sheets.

Here is a video from Alex Eames demonstrating the kit.

Waldringfield Demonstration Evening

On Thursday 5th November Ipswich Makerspace hosted a demonstration evening at Waldringfield VIllage Hall as part of their Winter Talks. The event was enabled by Waldringfield resident and Makerspace member Tim, apart from the Raspberry Jam earlier in the year this was the first real event to be put on entirely by Ipswich Makerspace.

A call was put out to members to talk, run demonstrations and just generally be around to help field questions. We had a very good turnout with the show piece being a display from Simon, more on this later.

Photo-2015-11-05-19-37-19_3053The event was opened with a talk both by Tim and then our Leader Steve, who had so much knowledge to impart his talk was cut down by about 80% by Tim just minutes before the speech, to allow time for the residents to actually see our wares. The talking went well and eager to learn more the residents streamed into the main hall and the Makerspace members did their work.

We had

  • Phil and Jon with quad-copters
  • Jon also brought along his 3D printer and Neopixel display with Snake running complete with home made score and leader board.
  • Phil bought along a couple of robots, a 3D printed one and the TractorBot 2015 prototype as well as a 3D printer and a PiTop laptop running last years Ipswich Makerspace PiWars video
  • Keith Ellis brought along last years PiWars champion TractorBot and also this years prototype Tractorbot 2015, both of which made their way out to the live arena for the kids to play with.
  • The real crowd puller though was Simon with his mind controlled racing cars
  • Plenty of other members were also present including Vince, Dan, Frank, Gary, Ben and I’m sure there are others I’ve missed. So thank you all for really making this event what it was, it was you who made it so successful and engaging.

    The event was very busy and the residents certainly seemed very interested.


    It’s been a while since the that post, largely due to getting the robot prepared. We still do not have a competition robot, we have a number of prototypes testing the code and various sensors, but the competition robot is still very virtual.

    Last years interface board

    Last years interface board

    The last week or so we have been working on PCB designs. Last year Keith made custom motor driver and interface boards on strip board, they worked very well but meant lots of late nights soldering. This year we were hoping to be more efficient and get purpose made PCB’s.

    Line follower mounting PCB

    Line follower mounting PCB

    The first of which was a very simple board to interface the line follow sensors. We have five sensors each with three wires, they quickly become tangled and hard to debug if things stop working. So we have designed a PCB that the five 4Tronix line follow sensors fit to. Keith will remove the angled header pins and replace with straight header pins so they can be soldered back to back with the new PCB. The PCB will have mounting holes so the other end of the sensor can be fixed with a screw fixing. The board has tabs to allow it to slot into the laser cut chassis.  On top of the board will be a pin header plug to allow us to run a common 5v, common ground and 5 signal cables to the Pi, reducing the amount of loose wires considerably.

    Line sensor PCB mounted to chassis

    Line sensor PCB mounted to chassis

    The board was designed in Ki-Cad and sent out for pricing, we went to the usual suspects RagWorm and OSH Park, they were very similar prices, but for the OSH Park price you get three boards, so essentially three times cheaper (if you need three boards). The killer though was the lead time, at least two weeks or more. Keith had a hunt around a bit further and came across Mitch Electronics, the service they offered was a bit more limited, the drill size range offered was smaller and the track widths and clearance had to be larger but there was a document explaining it all.  The level of service was also more customisable, for example it is possible to select which sides of the board you want solder mask and silk screen, the only caviate being if you wank silk screen (the printed text and component outlines) you could not put it on top of solder mask. The price was also equivalent to Rag Worm and OSH Park, the clincher though was the lead time, about five working days. So the order was sent off, there were a few issues with the files Keith produced but Robin at MitchElectronics was very helpful and quickly sorted them out.

    HAT style interface board

    HAT style interface board

    The first board is now ordered along with a second HAT style interface board which will mount directly to the top of the Pi.

    If all goes well we are expecting the line follower board at any time and the interface board early next week.

    So next, probably most importantly is to make a physical robot. Over the next week Keith will be sending the laser cut and 3D print files to Phil so the robot can start to be assembled. Since this is already built in a 3D model environment it should not take too long, just a few tweaks here and there.

    The main task is to convert the skittles ball launcher from 2D and get it in the 3D model so that a good fit can be ensured, oh, the trigger mechanism also needs to be designed. We still have three months to go, don’t we…

    Jon is also working on the wheel encoder system, which this year we have decided to use Hall effect sensors and magnets, more on this in a later blog post.

    Red light - Warning, laser enabled!

    Red light – Warning, laser enabled!

    Phil has also been working on the code and this was submitted for code review, although there are still some tweaks to be made. Phil also incorporated the laser guidance system in to the code.

    So it’s coming together and being tested on various prototypes, but it’s still a worry we don’t have a competition robot yet.

    Now where did I put that time machine…

    Code and 3D models

    A lot has happened since the last blog post, but we still do not have much to show for it.

    Jon has bee refining the proximity code along with his library for the VL6180 sensor. TractorBot now gradually reduces speed as an object is approached. Hopefully this will enable us to get extremely close. I’m still wondering how this be scored on the day, last year measuring the distances involved torches and calipers. Maybe this year feeler gauges would be useful.

    Phil, has been doing a general tidy up to the code and refining it where necessary. We now have a different control system called “Tank Mode”, this allows us to use the two sticks on the Wii Classic controller to control the left and right motors individually in a skid steer manner.

    Keith has been producing fancy virtual images of what TractotBot 2015 might look like.

    Fancy virtual model

    Fancy virtual model

    Chassis 7 - Small wheelsWhilst this looks very nice and has allowed Keith to design the robot in 3D ensuring all the parts fit together nicely, he was getting worried out how to make the virtual model a real one. It was simple to produce the STL files for the 3D printer but what was unclear was how to extract the data for the laser cut element. Anyhow, Keith plowed on, after all, the images did look very good.

    The wheels described in the last post have now been refined and Phil dutifully printed them out. The quick time lapse below condenses the 13 hour print job into a few quick seconds.

    First laser cut elements

    First laser cut elements

    A couple of days ago though, it all came together, Keith discovered how to extract DXF files for the laser cut elements, they were sent off to Phil for checking and he was able to use them with his laser cutter setup. So now the 3D model can become reality. Producing 3D images can be invaluable for understanding how something goes together and for getting an understanding on how something will work prior to actually building it. But now we have the possibility of 3D printing and laser cutting the elements directly from 3D model the whole build process becomes much more simplified. Last year the battery was held in place with a hair band and some blutack, this year however we have custom laser cut and 3D printed parts.

    The tool being used is AutoDesk Fusion 360, it is free for makers and tinkers and is quite easy to pick up and has some very good build in tutorials. It has software for OSX and Windows and there is an online collaboration element called A360 which enables team members to view and rotate the model and provide comments.

    Over the next week or so, Keith will be finalising the design and sending the files to Phil for printing and cutting. Hopefully soon we shall have an actual TractorBot to test and complete the code refinements.

    Wheels and 3D printers

    Lots has happened this week, but time is rapidly running out!

    Last week we got TractorBot up and running with a hacked together chassis and did a comparison with last years entry. Something that became clear was the size, the new motors and large wheels made TractorBot 2015 wider than a sheet of A3 paper, thus too big to enter. There were a couple of options

    1. Revert to smaller motors
    2. Get smaller wheels
    3. Mount the motors closer together
    4. Modify the wheels to the offset was reduced

    We really like the motors, they are not as fast as we hoped but are very powerful, therefore option 1 was out. The next three options however were all something we could work on.

    First we tried out the smaller wheels, the ones we tried were from Rapid. With luck they had the same size hexagonal hub so they fitted straight onto the 3D printed hub converters we had made for the larger wheels. The wheels were quickly fitted and went for a test drive.

    Apart from looking very strange, TractorBot was obviously a bit slower due to the smaller wheel diameter, but this has added advantages. It made the bot much more controllable and very precises. We feel this will make for a very good platform for the precision events such as three point turn and the proximity challenge.

    The next option was to mount the wheels closer together, this is an easy win and will be incorporated into the next chassis design, more on this in a later post.

    The final option would take a bit of effort but would help a lot in reducing the width of the bot. The current rims for the large wheels are designed in such a way that the whole wheel is offset to the outside of the hub fixing point. If the hub fixing point could be moved into the wheel then the wheel would start to overlap the motor shaft and create a smaller offset and thus a narrower bot.

    Since Phil had a 3D printer, Keith went off to design a new wheel, so out came the vernier gauge, off came the tyres from the original wheel and Keith duplicated the current wheel design into AutoDesk Fusion 360, this is free for makers and tinkerers and has some very nice features. The motors and hub adapter has already been modeled so Keith could put the three items together to make sure it all fitted together nicely.

    Wheels 3D printingEverything looked like it was going to work so the STL file was created and sent off to Phil for printing. The printer was set running, it was a mammoth job and the software predicted that two wheels would take eight hours. The print button was pressed late one evening and left to run over night. Morning came and this was the result, just over half way through. It was lunch time buy the time they had finished.

    Keith learned quite a bit about how to produce a 3D printable optimised model, if we get time we will blog about this separately. But for now, the wheel basically works and gives the desired effect.

    In summary, we now have a plan for making TractorBot fit within the size categorie for PiWars. Whilst doing so we have discovered we can 3D print our own wheels to our own specification and make them fit the tyres we already had. We also discovered that the robot was much more precise with smaller wheels. As such we now have the option to switch and change wheels to suit the task in hand. So now we need to carry on with the chassis design and start with the electronics. So much to do and so little time to do it.

    Introducing Jon Leach, team member

    Jon started out with computers when a family friend gave him an old MS-DOS machine in the early nineties. From there a string of different types of hardware, including many home built machines, quickly showed that Jon was destined for a career in computing.

    Jon LeachStarting with web site development using HTML and CSS Jon quickly progressed onto JavaScript, PHP and then Java. It was around this time that Jon began studying electronics at school and that sparked an interest in computer control and automation of real world objects.

    In 2004 Jon started a course studying Computer science at the University of Southampton. This introduced him to a whole host of new technology included object oriented development, linux and c/c++.

    In 2008 Jon moved to Ipswich and started a job at BT in Ipswich as a software engineer working at the one small part of BT that actually works on the phone network. Currently he works developing SIP soft switches for large corporate customers.

    Despite his day to day focus on software Jon has continued his interest in hardware and electronics. Home automation is a particular focus of his spare time but also robotics, 3D printing and multi rotor aircraft.

    Jon is the Ipswich Makerspace webmaster, has been involved in organising the first Ipswich Raspberry Jam and gives talks at several local tech groups.

    Joining the tractor bot team for this year Jon is focusing on adding additional sensors to further tune to robots performance in the various challenges.

    TractorBot prototype lives

    Last week Keith was scrabbling around in his shed to find a piece of hardboard to mount motors, motor drivers and Pi etc. Well it turns out he found some, so he knocked together a quick TractorBot prototype, the results can be seen below.

    The next thing to do was to download the latest Raspbain Jessie image and flash it to a new SD card. Keith had trouble with unzipping the download, but a quick check on the Raspberry Pi website showed that if the file was unzipped with The Unarchiver for Mac it would unzip fine, and it did. So after a quick dd command the SD card was flashed and the Pi was up and running.

    Keith then pulled the BitBucket repository to the Pi, installed the dependencies and fired up TractorBot.

    TractorBot 2015 prototype first test from Keith Ellis on Vimeo.

    Ooops, it didn’t work. It turned out that the motor driver earth was not connected to the Pi earth, once another jumper wire was installed it all worked as expected. So Keith tidied it up a bit, fixed all the components down and ran a side by side comparison against last years robot.

    TractorBot 2014 meets TractorBot 2015 from Keith Ellis on Vimeo.

    So now we know the motors and motor drivers work the next few weeks will be designing a proper chassis, this time hopefully it will be small enough to fit into the A3 category.