2nd K9 Continued

After a little work in the garage, I'm begining to see what I need to do to knock this body shell into shape. A little strengthening here and there etc and it should be good to go.

It looks much better with the excess fibreglass cut off.

The second control panel,

Second Head

The Idea is to cut a hole in K9's head to accomodate a speaker, but as I don't want to do major changes to K9 which I cannot easily reverse I thought it best to make a whole new head to work on.

and so it begins

The Gel coat took an exceptionally long time to cure, so I've ordered some fresh catalyst, but in the mean time I removed the part from the mould.

And did a little tiding up.

Now I'll have to wait for the new catalyst to arrive so progress is halted.

 

The head ready to come out of the mould.

Next the control panel and side panel. The side panel may take a little longer as I don’t have a mould for the side panel. The panel I have on K9-1 is plywood that is impregnated with resin and spray, but I can perhaps use it as a pattern.

K9 - head upgrades

Now progress on the control panel is coming to fruition, I need to look at wiring the I2C bus into the head. However when I came to look at the wiring, I've realised that a bit of rework is in order.

The visor Arduino Mega is mounted nicely, but the Arduinos for the radar ears and laser is very poor so needs sorting out before I add the extra wiring.

Spaghetti junction

After much work I've created an assembly for the 2 Arduino Nanos that control the ears and the laser, as well as a DC-DC converter an a signals distribution board. It is alittle tighter than I anticipated, but it is a removable module. 

Also it incorporates the I2C bus, so eventually they will take commands from the Raspberry pi, and not ust the control panel switches

Progress

K9 - Control Panel

This weekend I'm changing the button signals to I2C signals. I was disapointed to find that the Raspberry pi could only be a master so will not respond to I2C signal. It will only request data from slaves.

Pre - conversion pic

Progress is slow but getting there.

Nano support and some wiring

Arduino Nano One to control the LED's in the switches. Arduino Nano 2 to detect button pushes and send via the I2C bus. Arduino Nano 3 & 4 to control the LED matrix in 2 red displays. Only One LED matrix fitted and half wired.
Power and signals to the control panel through the 9 pin D-type connector.

K9 - Is there anybody home?

ROS on my pi

It was fun to build a K9, but there is something missing to my canine companion. That is intelligence!

With this in mind I'm investigating the Robot Operating System or ROS for short.

It has been painful getting it onto the Raspberry pi, as the instructions are not quite as complete as you would like and my knowledge of the raspberry pi is a little sketchy. Consequently it has taken about a week of the Christmas break to get it installed.

However, it is now on the pi (and backed up) and I've started on the actual ROS tutorials :)

So far I've got as far as driving around a simulated turtle, as above

K9 Diaries - 2017 Mini Maker Faire Derby

K9 had another outing, this time at the Derby Mini Maker Faire, at the Silk Mill Museum on the 28th of October 2017 and look who he snapped on his K9 cam.

Dr Lucy Rogers

Improvements since Whooverville are the tail mechanism and the visor lights, although there were some malfunctions with the visor lights, as some of them wer not working, but this turned out to be just some poor connections.

I usesd an Arduino Mega 2560 for the visor control, mostly because of the large number of I/O's available, and there is a connection to one of the switches on the control panel to change from all on mode to a Knight Rider function.

Below is the mounting of the Arduino Mega 2560, mounted on a plate, which slides into features which are bonded to the inside of the head, then a retaining clip holds it in. I just need to figure out the cable routing.

Arduino Mega 2560 mounted

I've since fixed and added a random function

The tail now also wags at the push of a button on the control panel. This is controlled by an Arduino Nano, with a simple sequence to a servo.

We  ordered a Tom Baker cut-out to pose next to K9, who was well received with many people having their photos taken with K9 & Tom and lots of  children had fun pushing the buttons.

I'm still working on improvements such as fitting the laser extender mechanism and the Software for the visor lights, which needs changing to an inturrept rather than waiting for the loop to finish before recognising the input.

K9 Diaries - Development

ADC and level shifter

The first job is battery monitoring, as I don't know how long to expect the batteries to last then it is important to have some feedback from them to determine their charge level. The Batteries at 12.4V each and the minimum discharge level is 9V.
A simple voltage dividing pair of resistors and a connection to the Raspberry Pi via the I2C bus has been made. The Adafruit library and example program has been added to the Pi and tested, so I just have to wire the inputs to the batteries and adjust the program to monitior the voltage and calibrate the output to reflect the true voltage.

K9 Diaries - Motor Controller Issues.

K9 wiring

The inside on K9 are pretty straight forward. There is a Sabertooth motor controller. Its a 2x32 generation 3 controller, which means it has a USB interface to an application called DEscribe. With this you can monitor the inputs and outputs, which is handy. You can also specify the battery chemistry and many other bits and pieces.

I've just fixed the motor controller location between the drive wheels, so it is no longer on top of the batteries.

The other upgrade is fitting the Arduino Nano to control the tail servo. Again a little more thought  when I was designing the wag mechanism, so there was somewhere to mount it, but ti-wraps to the rescue, and a mount from the walker robot and it is secure. The next iteration will have a dedicate mount point. The point is the tail which now wags!

I decided to fit the 4 switch elements in the control panel, and wire them, and the I2C pins of the control panel Nano to the D-type connector which I've used as an interconnect. The I2C pins are fur future use / development. One of the switches can now be used to activate the wagging.

The switches are a low level implementation but a first step in getting things going.

K9 Diaries - 4 days to go

Dog tag

Its come down to the last 4 days now, and I've persuaded Debs to make me a collar, and I 3D printed a dog tag.

The construction was easy enough, she covered a strip of leather with some tartan fabric and added some Velcro to the edges to fasten it. 

The D ring that the tag hangs from was taken off a collar that once belonged to her dog Mitzie, who died 17 years ago now, Debs kept her collar and thought it fitting to use a part of her beloved dogs collar on my beloved doggie project.


The 3D printing in the tag didn't stand out as much as I would have liked, so Debs applied a couple of layers of 'Empire Gold' Pebeo Gilding Wax to the raised areas, she likes it when she gets to use her hobby on our robotic projects.

head, primer and more filling

Unfortunately with just 4 days to go to the event, K9's head isn't ready yet and I've not figured out how to attach it to the body and its becoming obvious  that more filling is required.

After drilling the holes for K9's ears, and the visor cut-out, I primered the top of the head.

Debs seems to be getting worried, and keeps asking me if it will be ready in time! Whats that all about?

After a bit of sanding it'll be on to the top coat.

So I nearly have a head, but it is time to be thinking of having a couple of days off work to give K9 a better chance of being ready :)

 

top primer

Now the control panel is painted, I can move on to assembling the components. The bezels I've printed fitted into the 2 large holes and the 12 indicator lamps took no time at all to fit. If there is time, I'll fit 4 momentary switch contacts to the top 4 switches, and use these as manual operators of the ears etc

Wiring the control panel is time consuming, and the software for the Arduino isn't started, let alone complete.

Fortunately it's not a difficult job as there are plenty of resources out there for Arduino, and the experience with programming the Chompalots eyes and walker robots servo sequencing has put me in good stead.

K9 diaries - 7 days

Top of the head

7 days to go, and I've still not finished anything! I've still got a pile of unfinished dislocated bits. The head has at last been made and tidied up. I was scouting round trying to find something to use as a mould for the nose, but nothing was forthcoming so I modelled one on the CAD system and printed it on the 3D printer, then just stuck on with a bit of double sided tape to the head pattern before making the mould.

control panel mould

The control panel mould is a bit rough and ready but seems to have come out all right. I used copious amounts of wax mould release.

Below is the control panel and top of the head being produced in their moulds

The control panel is out of  its mould, and the Easylease release agent performed reasonably well,

Another package arrived today, hopefully the panel switch/lamps. The battery charger arrived yesterday,  so it is all coming together maybe.

Control panel, pre-tidy

I couldn't resist perching it on top of the body shell after I'd tidied it up a bit (below).

Now the control panel has appeared, the hole in the body shell can be made to suit it. Then the accommodation bits to stop it falling straight through need to be added. Then it is on to the body being  primed and painted, after a bit of sanding. This would be a massive step, when K9 starts  to come into view.

trial perch

Once the body is painted all the systems can be fitted and integrated. The sub assemblies collected together and we will see what problems and missing bits we still have to sort out.

The side panel is going to be a major part which needs making. There is no primer remaining and I think I need some more MDF!


My attempts at tagging K9, with primer at this stage

 

 

K9 Diaries - 11 days to go

Head Mould

Only 11 days remaining before the appearance of k9 the wonder dog, so I'd better get my skates on. Fortunately I've been working slowly but steadily towards the ultimate goal. Sometimes it seems like he'll never be done, and so many different things to organise, and co-ordinate, with things slowly lumbering into position, it's like the aligning of the planets.

Fortunately the head mould did come apart mostly OK. Just a little sticking on the front of the head in the mouth area. Relatively cleanly, so only a little tidying up and it and it should be good to go.

The control panel is also progressing, this needs to be completed so I can gauge to correct size for the hole to accommodate in the body. Then I can move on to prepping and painting, before fitting all the systems in the body shell.
I decided on a two part mould. Hopefully the two parts will pull apart easily. Again with the experimental, I went for plain MDF with no primer, just 6 or so layers of wax release agent, all holes and imperfections filled with wax.

Both sides of the control panel mould are now covered.

K9 Diaries - A Body in the Garage

Removing the mould

It began like any other evening, visiting family, what I really wanted to do was to get home to deal with the body in the garage. I had quietly secured it the previous evening, and I just needed time for the idea to gel. When I finally got into the garage, it was like driving a wedge between reality and a shadow. How would it turn out, would this be the end of a dream? Would the Fibreglass police turn up at my door and charge me with insufficient application of release agent?

One side revealed

After the wedges had been gingerly tapped in, the mould began to release again quite easily at the top, but it seemed to be sticking in the recesses again. Oh the torment, until with a cracking sound it just popped off. I was so relieved!

It also looked quite good for saying I'd taken a chisel to the mould.

Then it was on to the other side, I wasn't out of the woods yet.

Right side and front.

I was on a roll, the wax release agent is definitely is the way to go. Perhaps I'll try Easy Lease again in the future but I'll test it out on some not so important bits before I roll that dice again.

Here are three sides revealed, it was going too well!

Time for the bum

The rear section was a little  tricky, I thought it was going to give me some problems, but in the end just a little gentle teasing and plastic wedges tapped in all round, was all that was required.

The top section was a breeze. So this is it, K9 has a body shell, just a bit of a trim to remove the excess fibres around the edges and a little light sanding required around the edges.

K9's body revealed

Photos by my lovely wife, Debs :)

K9 Diaries - 3 Weeks to Whooverville 09 - PANIC MODE

Front and rear panels

After soaking the MDF and then scraping the primer off with a chisel, I've finally got a mould. There is still work to do cleaning it up, so I believe I need to fill any defects and then give the panels a light sanding.

This will probably take me through the weekend leaving less than 3 weeks to finish K9. Oh woe is me.

3 Weeks and counting - The situations is: Still no body, head, side panel or control panel.

The Motorised base is still good, and batteries have arrived, but charger needs sorting out.
Raspberry Pi is good, I2C connection to Arduino works.
Screen is good and the HiFi Berry should be great.

If I  can press on with the fibreglass this weekend, I may have a body shell and maybe a head.

The control panel could be fabricated quite quickly, and side panel is a quick job (famous last words).

So just a bit of filling where required, then onto waxing before fabricating the body shell......

It's a mould, huzzah. Not as pretty and shiny as it could have been but hopefully serviceable. With six coats of wax mould release agent, I'm pressing on!

Still no head, and I'm dreading trying to remove the bit's I've attached.

K9 Diaries - Sticky Situation

With high hopes, I started gently inserting wedges and tapping them in. The mould should have just popped off.

After carefully working my way round tapping in wedges, it became apparent that it wasn't going to be that easy.

Unfortunately the release agent hasn't done its job. Rather than separating easily, I had to apply excessive force, which ripped the recess out of the pattern.

Wailey, Wailey!

I now had a big hole in the pattern and was quite anxious about the rest of the mould.

This is strange because the top half has released reasonably well, but in the worst possible places, the recesses, the mould has stuck to the pattern.

I messaged easy composites to get their take one the situation and was told that on new moulds they recommended 6 coats Doh!

So the issue was repeated on all four panels.

Side panel
The same with the other side, as well as front and rear.

In the end, I've had to demolish the entire K9 pattern to get the mould off.

This could slow things down a bit :(

And here's the remains of the K9 pattern, 'tis but a scratch. I'm sure that with a bit of glue and a polish we can get it back together and have another go.

The plan moving forward is to remove the MDF from the mould. Then it's the primer coat that'll need scraping off. Then clean up the surfaces.

No doubt a little filling and sanding here and there, but don't get too hung up about scratches in the surface just light sanding and smoothing.





After a day of soaking and scraping, the majority of the MDF is removed, but the primer is still attached. 

I've had some success scraping the primer off with a chisel, as long as I don't scratch  the mould surface too much it could be the way forward. Either way it's a lot more work, and time.

K9 Diaries - Full Glass Jacket

Side prepared, ready...

The last side, it's been a long journey, but it is nearly over, It seems like I've been making this part forever, I've made a body, only to make a shell round it. So very soon I can move on to making the the actual body shell, that will be K9!

The final count down

I've received some more matting, this lot is a heavier weight so will make thicker layers, but will also require more resin.

Today, I've given the right hand side of the pattern a coating of  fibreglass, so that's all the sides done. I'm concerned that I may not have made the layers thick enough, but we will see how it goes. The thicker matting seemed to be easier to work with than the lighter weight matting I was using, so in future I'll use the 450g/square metre

Ready to break apart

After a bit of tidying, removing the hairy perimeter, we have a clean edge to see the interface between the mould pieces. I've drilled holes to hold the pieces together when it's being used as a mould.

Tomorrow is the big reveal, the unwrapping day, when I'll find out what sort of a job I've made of it.

Still if it's a dogs dinner I've still got time to have another go......maybe...So tomorrow will probably be more prepping for the big day.