In this video I look at some of the features of the Arduino and the Raspberry Pi to see which is the best fit for your project.
Whilst it starts with the answer “it depends”, it gives scenarios where each is better and for those where either is a good fit I’ll give my own opinion of which is best.
I then explain about how you can get the best of both by combining a Raspberry Pi and Arduino and what the options are for communicating between the two.
This is really an introduction into a future video showing how both can be used together.
Blender is well known as a 3D modelling tool, but it is also good for creating 2D animations. It includes the ability to create timeline based animations using Keyframes with automatic tweening and fine control over all the objects.
If you don’t know what that means then hopefully this video for beginners will provide a useful introduction. I’ve also created a video on using the shader editor for those ready to take the next step towards mastering 2D animations.
It’s always been possible to create 2D animations in Blender, but the video above introduces the new 2D Animation option on Blender 2.8 and Blender 2.9. This isn’t a separate tool, but a different workspace, and arrangment of the tools and camera to make it easier to create 2D animations. This is particularly useful for creating 2D animations which can be included in your YouTube videos. This is a relatively new feature which was introduced in Blender 2.8. It does not work with Blender 2.7 or earlier.
The tutorial is a beginners tutorial video which goes step-through-step explaining the process needed to create the animation. The example shown is of a airplane which flies across the screen.
For the images it uses the Blender Add-on “Import-Export: Import Images as Planes”, which makes importing the images easier. It also demonstrates how text can be used in a 2D animation.
The technique used for hiding the image is to exclude it from the render. This is a simple technique for beginners, but does not offer much flexibility. I will provide details of how to use the Shader Editor in a future video.
This video gives a much better way of manipulating images in blender by using the Shader Editor to manipulate the material output.
This provides a way of hiding the 2D images, but also shows how different textures can be used including using an image mask to hide parts of another image, all within blender. This solution also works well with keyframes and as well as rendering better.
The Shader Editor provides a way of performing mathematical operations on the alpha value which changes the transparency on a pixel by pixel level of details.
There are other textures that can be applied to the image and material.
The final example shows how a image mask can be used to show bullet holes in a plane.
The image files used in this 2D animation are the same as the files shown above.
An example video
Another example showing a simple animation in blender is included below. This shows a simple hammer and screwdriver example.
Ubuntu 20.10 is now available as a BETA release. This includes a Raspberry Pi server edition. In this video I will boot up from a newly created image using the image from Ubuntu 20.10 Beta Server images site.
I then show how it can be setup as a basic web server with a simple test page created in html.
This is just the first steps in setting up a web server as it only installs Apache 2. You may also want to install a database such as Maria DB or other applications. You will probably also want to change to a static IP address which is not shown in this video.
The console screen video is captured using gucview, then I use an ssh from my Ubuntu PC to complete the configuration.
This was tested using the beta image installed onto an SD Card. I have tried to boot from an external USB drive (eg SSD drive), but that was unsuccessful.
Posted in Computers, Linux, RaspberryPi|Comments Off on Setting up a web server on a Raspberry Pi 4 using Ubuntu 20.10 (Beta) 64-bit Linux
This is a review of the PowerUP 4.0. This is a successful Kickstarter campaign which completed in 2020. I’ve received my bundle of airplane related goodies and had a few builds and test flights.
The video below goes through an unboxing, the first builds, test flights and important information on flying the plane such as the minimum amount of space needed to fly.
This last part is very important. I nearly lost the airplane on my first flight due to it landing in the middle of a bunch of bramble bushes. It was only my determination to retrieve it that convinced me to walk through chest high brambles to retrieve the plane.
On Kickstarter I backed the pro early bird level. This cost $79 and included the following:
POWERUP 4.0 Module
4 Red Paper Plane Templates
Desk Stand
10 Additional Paper Plane Templates
2 Waterproof Dupont Paper Plane Templates
Night Flight LED Lights
Wheels for Take-off & Landing
Foam DIY Kit F22 Style Aircraft
A good part about the Kickstarter is that they did offer an option to upgrade the parts at the end, by buying any of the features not included in the level that you backed.
Kdenlive is a free open source non-linear video editor. I used to regularly use Kdenlive for editing my videos, but I switched to a commercial mid-price video editor a couple of years ago. This is because I found Kdenlive to have a number of bugs and was difficult to get the effects that I wanted. The main disadvantage of switching was that the commercial software was Windows only and as I create many of my screencast based videos using Ubuntu it meant that I had to boot into Windows.
I’ve recently decided to give Kdenlive another go and I was blown away by how much it’s improved since I last used it for any serious video editing. Not only does Kdenlive look good and is stable (I haven’t come across any major bugs), but it’s also easier to use than the other software I was using. I’m so impressed that I’ve ditched the commercial software and now I’m sticking with Kdenlive for the foreseable future.
There is some other commercial software that is better than Kdenlive, but for that you are probably looking at very expensive licensing. There is also some free video editors which are easier to use (such as OpenShot), but without quite the same power and flexibility as Kdenlive. For me it just hits that perfect spot between ease of use and powerful features. That it’s free is a bonus as well. I’d like it to improve further so the money I would have considered spending on commercial software I’m going to donate to the Kdenlive project in the hope that they can make it even better in the future.
Kdenlive is available for Linux and Windows, it’s fairly easy to use although it does still have a few quirks (like having to drag files into the project bin before you can drag it onto the timeline), but it also has some things that are easier to use such as volume control of the clips. It does need a lot of memory. On Linux I originally had only 8GB of RAM which works for short videos, but on long videos it ground to a halt. I’ve since upgraded the RAM (to a whopping 24GB – although I’m typically using only about half that) and it runs pretty fast.
Posted in Computers, Days Out, Linux, Web Design|Comments Off on Kdenlive – editing videos using a professional free open source non-linear video editor
In the UK the coronavirus / covid-19 lockdown is starting to ease. Most recently Zoos have been amongst the list of attractions that are now allowed to reopen. This is our first visit to a zoo since lockdown and our first experience of a post lockdown day-out, other than visiting a local park / woodland.
We have a number of zoos and a safari park a reasonable drive from our home, the one we decided on was Dudley Zoo and Castle. This is a zoo we visit regularly and I’ve written about the zoo before, although that was 10 years ago. Dudley Zoo at Easter 2010.
There are a number of changes to the experience specifically due to the Covid-19 restrictions. The first was having to book in advance. We went at a weekend and booked online several days in advance; the Saturday was almost fully booked, but fortunately there were quite a few time slots still available for the Sunday. We bought tickets for the Sunday with an arrival time of between 1pm and 1:25pm.
I do sometimes book days-out in advance particularly if there is significant savings but more often we don’t decide where to go until the day in case of bad weather or if we change our plans, but that is not an option at this time.
Upon arrival we were told that there were changes to the visit including a one-way system around the park and told to avoid touching enclosures / windows and to wash hands regularly. There are already plenty of hand washing stations (for the “up close” encounters which are closed) and hand sanistiser foam was also placed regularly around the site.
The zoo was certainly popular, but with restricted numbers and fixed arrival times the zoo did not feel crowded at all. It was sometimes neccessary to queue to see inside a particular enclosure (particularly at the glass windows), but that worked well. Most people were observing the social distancing although there were some people that didn’t (or perhaps just forgot about it). There was only one place where the social distancing appeared to be completely forgotten and that was near the sea lion where a number of people were crowded around to get a look. Even with the relative close proximity around there it was certainly nothing like the photographs that have been circulating about overcrowding at Bournemouth beach. We just went past the crowd and observed from a distance.
Although looking at the map there were lots of closed attractions these didn’t appear to be a bad as it first looked as some of these were just certain vantage areas and most of the animals were still visible. One thing we were aware of was the land train and chair lift were not running (the chair lift would have been closed due to high winds anyway). As Dudley Zoo is quite hilly this meant that you had to walk up the hill, however they did create a one-way system which went around the zoo following a more gentle climb up the hill than some of the alternatives. Another thing we were aware of is that the restaurant and bar were both closed. There were some kiosks but they had a limited range of drinks, ice creams and sweets. We took a picnic along and ate that at one of the many benches.
Some of the close encounters or indoor exhibts were closed including the lorikeets, wallabies, lemurs, farm, chimpanzee (there was just one in the outside area) and reptile house. The funfair rides were also closed although as they are mainly for young children our children are now too old for them anyway. The gift shop was open but operated a one way system making it difficult to decide what to buy without needing to go back through the shop.
Summary
The experience of visiting the zoo was certainly different, but still well worth visiting. It’s a shame that some of the close encounter exhibits were closed, but there was still plenty of other animals on show. Whilst you had to walk a certain away around the zoo this was just a different way of experiencing the zoo. There was no need to be at a certain place at a certain time so it was just a case of going around at your own pace and enjoying the animals.
It was a good day out and good value for money. With the extra restrictions and hand cleaning available it felt like a safe place to visit whilst coming out of Coronavirus / Covid-19 lockdown.
Posted in Children, Days Out, Photography|Comments Off on A trip to the zoo – after coronavirus Covid-19 lockdown
The Raspberry Pi is now available with 8GB of RAM. The cost is higher, costing almost twice as much as the 2GB version, although only about £25 more than the 4GB version. The question is what can you do with 8GB of RAM and do you really need that much?
The fact that you can now buy a Raspberry Pi computer with 8GB of memory for $75 is a huge achievement. It’s something that wasn’t possible a few years ago. Whether you need one just yet is up for debate.
Since then I’ve been listening to feedback from my viewers and those on social media and it seams people would like to see a test for Power Users. So here is a test to launch as many applications as I can to see at what point it would benefit from the extra memory, whether you have a 1GB, 2GB, 4GB or 8GB model.
Whilst you are here, please consider subscribing to PenguinTutor on YouTube. The more subscribers I get then I know it’s worth me continuing making videos on my projects. It doesn’t cost you anything to register and subscribe and hopefully you’ll enjoy some of my future videos.
Testing Memory Usage of the Raspberry Pi 4 – 8GB
Here’s a list of the applications I ran to hit the various memory thresholds. Note that I didn’t close any of the applications, so each list is incremental from the previous entry.
1GB
Raspberry Pi OS (32 bit)
VNC server
OpenSSH server
Shell with htop
Chromium Web Browser
www.penguintutor.com
www.watkissonline.co.uk
Gmail Inbox
Facebook home page
Twitter logged in
BlueFish Editor
Fritzing
KiCAD
Mu Editor (IDE) Pygame Zero game (Compass game)
Another two shells
LibreOffice Writer – with large document
LibreOffice Impress x 2
libreOffice Calc
LibreOffice Base
4GB
LibreOffice Draw
Minecraft
GIMP 2 images loaded
OpenShot with large HD video file
KdenLive with HD video file
File manager
VLC with HD video loaded
5GB
Inkscape
Blender with demo file
slic3r
makehuman
Mathematica
Wolfram
PCB New
Bitmap to Component Convertor
eeschema
Greenfoot Java IDE
6GB
VNC Viewer
SmartSim
Scratch 2
Sense HAT emulator
SonicPi
Thonny Python IDE
Claws Mail
ImageMagick
Bunner Game
File manager
PDF viewer with large PDF file
Calculator
Code – OSS (headmelted)
Summary for desktop use of Raspberry Pi 4
Based on this testing I still don’t think there is a need to have more than 4GB for using a Raspberry Pi as a desktop computer, at the moment. It’s possible to exceed the 4GB of the next model down but I had to launch so many applications that it just wasn’t realistic.
This may change in future and it can potentially open up new opportunities for the Raspberry Pi. Areas that were previously out-of-bounds for the Raspberry Pi are now becoming possible. Paying an extra $25 for the 8GB version can help future proof your Raspberry Pi.
Non desktop use
Beyond the desktop there are other areas that may make better use of the 8GB of memory on the Raspberry Pi 4. You could perhaps look at using a RAM disk to speed up the Raspberry Pi as well as reducing the amount of writes to the SD card if you have a system that is prone to power loss (eg. a remote monitoring device).
It may also help with running a network server by allowing a large number of server threads or caching database information.
The fact that you can now buy a Raspberry Pi computer with 8GB of memory for $75 is a huge achievement. It’s something that wasn’t possible a few years ago. Whether you need one just yet is up for debate.
On top of my job, family and computing interests I’m also an assistant Cub Scout leader and a member of the District Executive Committee (Charity Trustee of the Scout District). During the current Coronovirus / Covid-19 pandemic we are unable to meet face-to-face but scouting is still happening through virtual conference sessions I am running on a weekly basis and executive meetings which have moved to Zoom.
The local Scout County are also running challenges for members young and adult, including this weeks’ leaders challenge “Why I Scout”. So here’s my story and the reason I am involved with Scouting.
Previous Experience of Scouting
I have been a Scout throughout my youth. I joined the Cubs when I was 8 (they didn’t have the younger Beaver section in those days) and continued up to Venture Scouts (now known as Explorer Scouts). As an explorer I used to help out at the Scout troup (what would now be a Young Leader) and when I went to University I became an assistant Scout leader near my halls of residence. I countinued scouting briefly after leaving university but the meeting night clashed with other activities and due to my other volunteering with St John Ambulance I left scouting for about 15 years.
Why I came back to scouting
I rejoined scouting thanks to my son. He was the one that made me realise what I’d been missing the last few years.
My son joined the local Beaver Scouts, which is something I’d encouraged as I remembered how much I had got from being in Scouts. It was when he moved up to Cubs and I took him to his first Cub camp that I realised that I still had the Scout inside me wanting to get involved. Although I’d never been to that campsite before, the moment I arrived I was transported back to my own experiences of Cubs and Scouts and the fun I’d had.
It actually started with trepidation of dropping my son off for his first camp but when I dropped him off and the Cub leader had him help making a campfire that’s when I realised I didn’t want to drop my son off for a weekend; I wanted to be there with him enjoying the experience myself.
So that was it. It also happened that the group was short of leaders and at the AGM later that year I put my name forward to “help out”. Initially I was planning to be a sectional assistant but after my initial meeting with the training advisor I changed that to assistant cub scout leader. Three and a half years later and I’ve now completed the requirements for my Wood Badge (Scout leader training programme) and I’m still very much enjoying Scouting.
My only regret is that I didn’t get back involved years ago.
What do I get out of Scouting?
Scouting for me is about enjoying the experience as much as giving back to my local community and supporting the young members. It’s an opportunity to meet new people, make new friends, learn new skills and have fun doing so. It’s also great to be able to provide opportunities for the young members and to see them learn new skills and develop in confidence.
Being a scouter is being part of a huge family with members all over the world.
Scout Leader Training Location
My future in Scouting
Scouting can take up a lot of time (Spoiler alert – it’s more than 1½ hours per week).
Although I am able to find time for scouting, due to family commitments over the last year I have been finding it harder to attend the regular Cub meetings. At least I was prior to lockdown, during lockdown I’ve been running regular meetings for the whole group including the Beavers and Scouts as well as my Cub pack.
One of the good things about scouting is that there are lots of other opportunities for different roles either hands-on with the young members or providing support to those that do. I think my involvement in Scouting will be changing in future I am confident that I will find a suitable role that allows me to continue being a part of the scouting family.
What I’d say to others
If you are wondering whether Scouting could be for you then I suggest you don’t delay and find out today. Get in touch with your local Scout group or through Scouts website. There are always positions available as the more adult volunteers that are involved the more young people that can be supported and the better the opportunities for our youth members.
Scouting hasn’t stopped during lockdown, although it has changed temporarily. It would be a great time to get involved and learn more prior to resumption of normal face-to-face meetings.
Although it can take up lots of time it’s an enjoyable experience. If you can’t make every week then there are opportunities to be an occassional helper or to help behind the scenes in supporting the activities.
Also see
See the following YouTube video for another ShireJammin Challenges I’ve completed.
The Raspberry Pi is now available with 8GB of RAM. The cost is higher, costing almost twice as much as the 2GB version, although only about £25 more than the 4GB version. The question is what can you do with 8GB of RAM and do you really need that much?
The fact that you can now buy a Raspberry Pi computer with 8GB of memory for $75 is a huge achievement. It’s something that wasn’t possible a few years ago. Whether you need one just yet is up for debate.
Full details are explained in the following video, which shows how I tested this. It’s not quite real world setting, but I’ve tried to at least launch the same applications that you may expect to have running at the same time.
Whilst you are here, please consider subscribing to PenguinTutor on YouTube. The more subscribers I get then I know it’s worth me continuing making videos on my projects. It doesn’t cost you anything to register and subscribe and hopefully you’ll enjoy some of my future videos.
Testing Memory Usage of the Raspberry Pi 4 – 8GB
To perform the test I connected the Raspberry Pi 4 to a NexDock 2, and a computer monitor. A 32GB SD card had the latest Raspberry Pi OS (full install) and the latest updates were installed. I enabled ssh and VNC and used SimpleScreenRecorder to capture the video from the Raspberry Pi NexDock screen.
I launched various office applications, a web browser with a few tabs open and tried OpenShot. I didn’t open many large documents, although I did load some videos into OpenShot and set it rendering the video (I cancelled the video rendering as it woul have taken too long for the video demonstration).
Measured memory usage of Raspberry Pi 4 8GB
In use I didn’t manage to get the memory usage much above 2GB, suggesting that the 4GB version is probably up to most peoples requirements.
CAD on a Raspberry Pi 4
One task that I did think would use more memory is CAD (computer aided design). I did try and run FreeCAD, but that failed. I think this is due to it not working with the OpenGL graphics drivers on the Raspberry Pi. I do think that is one place where the extra memory would be useful. Although not tested in the video Blender could be another one, it does run in a reasonable amount of memory (as I have used Blender on the older versions of the Raspberry Pi), but complex designs may benefit from the extra memory.
I also didn’t try 3D printer slicers. I know that for Cura the latest version is compiled for 64 bit Intel only, but that is something that may be possible in future.
Summary for desktop use of Raspberry Pi 4
Based on this limited testing I don’t think there is a need to have more than 4GB for using a Raspberry Pi as a desktop computer, at the moment.
The testing was not full real-world use and perhaps it may be possible to go beyond 4GB by loading large documents, although I still don’t think that most users will need more than 4GB.
CAD is one area that may benefit, but I was unable to perform the test of FreeCAD for this test.
This may change in future and it can potentially open up new opportunities for the Raspberry Pi. Areas that were previously out-of-bounds for the Raspberry Pi are now becoming possible. Paying an extra $25 for the 8GB version can help future proof your Raspberry Pi.
Non desktop use
Beyond the desktop there are other areas that may make better use of the 8GB of memory on the Raspberry Pi 4. You could perhaps look at using a RAM disk to speed up the Raspberry Pi as well as reducing the amount of writes to the SD card if you have a system that is prone to power loss (eg. a remote monitoring device).
It may also help with running a network server by allowing a large number of server threads or caching database information.
The fact that you can now buy a Raspberry Pi computer with 8GB of memory for $75 is a huge achievement. It’s something that wasn’t possible a few years ago. Whether you need one just yet is up for debate.
As a STEM ambassador, I’ve done quite a lot of practical science lessons with my children and primary age school children. There are lots of science books that you can get full of experiments that you can do at home. When they reach secondary school it’s a little more difficult without having a science lab at home. Not only do science experiments need special equipment including a bunson burner, but they also need a bunch of chemicals that you can’t just get from your local supermarket (or not in their pure form at least). So about a year ago I subscribed to Mel Chemistry which is a monthly science subscription service. You start with a set of basic equipment and then each month you get a pack containing most of the chemicals you need along with simple step-by-step instructions to complete the experiments (usually two or three related experiments) and an explanation of the science behind them.
I’ve been slowly working through them with my daughter who is very keen on science, but my son hasn’t really taken much interest. That is until today when I was helping my son with science during the coronovirus / covid-19 lockdown and school closures. His lesson included watching some videos and answering some quizzes which he worked through and then I suggested getting out the Mel Science kits and looking for a related experiment. We found two experiments that fitted well which my daughter had done with a friend. As the Mel Science kits include enough of the chemicals to complete the experiments twice we had everything we needed.
The topic my son is covering in science is acids and alkalis and the practical experiments were both around PH indicator which is a perfect fit with the school lesson. The experiements we did were:
The experiments are usually easy to do and usually take between about 10 minutes and 40 minutes. Whilst almost everything is provided you do sometimes need to buy some items yourself. One is Hydrogen Peroxide which I already know as something you can buy from most pharmacists (used in elephant toothpaste catalyst experiments I have done with the Cub Scouts). The one thing I still need to find is starch, they sell it in an aerosol at a local supermarket but I’ve not been able to find a suitable source at the moment.
Aside from this little thing the kits have been really good. The experiments have clear instructions and almost always work first time as long as you follow the instructions correctly. It’s been useful to encourage my daughter’s interest in science and even more so with schools closed. I’ve also learnt some more about chemistry as well.
Note: This is purely my own opinion. I have no involvement or affiliation with Mel Chemistry other than as a paying subscriber.
Also see – Mentos and Cola science experiments
Here’s a video I made several years ago of a simple science experiment involving mentos and coke / cola.
Posted in Children, Days Out, Linux, Reviews|Comments Off on Creating practical science lessons for home schooling during Covid-19 lockdown
