This portfolio will demonstrate the new skills developed over the course of this unit. Using fusion 360 to digitally model has benefits and drawbacks like any software which will be highlighted and some comparisons to other software such as Solidworks will be made. Additionally, the physical modelling side will be discussed with reference to FFF machines such as the Ultimakers 3 which will be used to 3d print the prototype model. Other software such as Cura used during the design process and any other new skills in relation to this unit will also be addressed.
Creating virtual model
In this section I will discussed any new skills that I have learned while using fusion 360.
Importing images and SVG
An important feature in creating some of the models particularly the spider model was the insert tool. This allowed me to firstly insert a picture which has been saved to the desktop by first selecting the face or place where it will be placed then selecting the image. The same processes can be repeated to import an SVG file. SVG files can be edited using software such as adobe illustrator then saved as an SVG file before importing into fusion using the insert tool. Using an SVG you can extrude shapes which have been created outside fusion
This is another feature which saved me a lot of time when designing both the Rubik’s model and the spider model. For instance, fig 2 shows the top of the spider model which has venting holes on both arms of the model in symmetry. To create this, I focused only on one side of the model then the mirror command copies and flips sketch entities across a line of symmetry and creates a relationship between the mirror and original entity.
To create the length and width of the model I used the rectangular pattern command. Instead of manually drawing each instance, the rectangular pattern command takes the original geometry and replicates it across the sketch with a specified spacing and number of instances. Once the base was created, using the same tool to then create the height of the model.
Projection command was mainly used to copy the edges and dimensions from the Arduino boards ports and pins. By projecting the sketches onto the top and base of the model I was able to make the cut outs for the power source and USB. This command was used again to create the cut outs to on the top of the model to allow access to all ports and pins.
Edit feature using timeline
As with most design projects my designs required modifications and to be redesigned at some point. Using this feature the ‘edit feature’ on the timeline I was able to easily go back to any point of the design identify and make modifications then continue once the changes had been made. This was especially useful when testing the model for 3d printing. My Rubik’s model was tested, and I identified that the space around the PCB was less than 3mm so did not meet the brief. Instead of starting from scratch I adjusted the pin on the timeline back to the start and changed the dimension of the first cube to fix the problem.
Creating construction planes
Creating construction planes has become more useful the more I understand how it works. Initially challenging but now helps me create sketches at angles and positions which would be hard to achieve otherwise. For instance, when creating the top and bottom of the model I used the mid plane command to identify the centre of the model. Using that plane, it was then possible to make a cut out in the middle of the model using the split tool. Each construction plane is then added as a parametric feature in the timeline, allowing for them to update as necessary when modifications are made.
Create a thin wall solid body
The shell feature is a powerful and time saving which allowed me to hollow out material and create thin walls in the part. Using this feature, I was able to create a shell for the Arduino with wall thickness of 2mm.
Did not have much use for this tool except when I had to drastically reduce the size of my spider model. I found this tool difficult to use as it affects features of the timeline and creates a lot of errors which then needed to be individually fixed. Another instance in which I used this tool is to reduce the size of imported objects such as the desk which the enclosure would rest on. Instead of being required to alter the sketch dimensions and potentially needing to update all of the associated features, simply scale the model to the desired size and fix any features which have been affected.
Create a 3D section view
The Section Analysis tool creates a section of a model so that you can see inside it. When complete, Fusion 360 adds the section view to the Analysis folder in the browser. This allowed me to check the internal components of the model to ensure everything fits correctly. For instance, it was vital that the Pins which slot to hold the enclosure together where extruded enough to hold in place. To check this, I used the section analysis tool which is shown in fig 6.
According to Autodesk a Rigid is probably the most commonly used Joint Type when starting out. Rigid locks components together, removing all degrees of freedom. This feature was used to fastened to the arduino board to the pins attached to the base of the model. I found this tool simple and easy to use and ideal for all models in this project.
Learning about the Ultimaker3
Ultimaker3 uses Fuse filament fabrication (FFF) technology with Dual extrusion print head with an auto-nozzle lifting system and swappable print cores. The build volume of XYZ 215 x 215 x 200 mm. Ultimaker have a free print preparation software Cura but also supports plug in such as Solidworks, Siemens NX, Autodesk Inventor.
Before testing the model in cura I first saved the model as an STL file which I found produces the most accurate results and needs very little adjustment. Using the built-in chamber in cura I was then able to place each half of the model face up to reduce the amount of support material needed for the print.
Firstly, used a scalpel to remove the excess support material which was attached to the base of both parts being careful not to remove too much material. Then using a range of sand paper from MMU’s blue room to file the rough edges down to create a smooth finish ready to be painted.
As each section had to be painted in a different colour I though it best to print the material in one colour (white) then I would paint each each face in a different colour. Importantly to get the rubiks theme I had to paint the fileted edges and corners in a single black colour to divide the colours.
The results were not what I hoped for, the acrylic paint used did not take well and It was hard to avoid any smudge which takes away from the aesthetics of the design. For these reasons I decided to re print the model and paint using shoe polish which I have used previously and had much better results. However as with many 3d project I experienced difficulties which lead to a failed print. The filament rapped around the plastic coil which holds it together was jammed which resulted in a failed print. Although I am very disappointed this does represent an issue which I am likely to face in the future therefore I will need to plan for several failed attempts before I achieve my final model. This has been a vital learning curve for me.
Overall found this unit to be engaging both mentally and physically. The process of learning the basic principles of fusion has been both challenging and rewarding. Although fusion 360 is a relatively new software to myself I found it to be user-friendly and easy to use. The interface can be customised to suit different preferences for example changing the interface to match that of Solidworks for users who are more familiar with that software which proved to be very useful. Fusion also connects your entire product development process in a single cloud-based platform that works on both Mac and PC. This proved to be both useful and a pain as saving information was simple and all in one space with no need to additional storage such as a USB drive. However, there was an issue when saving work on a device which has the updated software then trying to open the document on a device with an older version of the software. This resulted in me losing some of the original models created and occasionally not being able to open documents that have been saved to the cloud. One way around this was to download the most up to date software which then allows you to open documents saved to the cloud, however, as this not a personal device the updated software would have to be downloaded each time you log onto the device.
In order to understand the principles of fusion I used information from Autodesk learn and create forum as well as Lynda which provided the latest information on fusion from industry experts. Although there was a lot of information to go through it vital to find any updates in tools and information which could help to save time on my project and improve the overall aesthetics of the model. For instance, learning to use the model pattern tool saved me having to sketch each segment of the cube which saved both time and produced a more accurate representation of a Rubik’s cube.
One major problem faced was scaling to make sure the model would fit within the build chamber and an appropriate size for its intended application. First encountered this problem when trying to print the spider enclosure model (fig). The shape of a spider posed a design problem as I could only fit the Arduino board within the main body, the arms and head where for aesthetics purposes only. For this reason, when I scaled the model down to a size which would fit the build chamber of the Ultimaker I then had the problem of the Arduino not fitting the main body. To address this problem, I changed the orientation of the board horizontally, which allowed me to reduce the size. However, as the build time was significantly higher (roughly 2 days), I decided to print my Rubik’s model which printed within 14 hours.
My first attempt at 3d printing the rubiks enclosure was a real learning curve. Although the model was not a disaster it did highlight issues which i had overlooked during the digital modelling stage. For instance the PCB fitted perfectly onto the pins created and the rest however there was less than 3mm clearance around the board so this model did not meet the brief. Additionally, I realised that i had included some access to ports and pins but others where missing. On the other hand this failed attempt also highlighted what worked well about the prototype model. For example the pins created slotted seamlessly to hold the enclosure together and allows access to the PCB within 60 seconds. Impressively there was very little post processing to do the support material was removed quite easily with a scalpel and using sand paper i can achieve a smoother look before applying paint.
Research Into the Rubik’s cube
Rubik’s cube is a toy puzzle designed by Erno Rubik during the mid-1970s. It is made up of smaller cube pieces with six faces having differing colors. The standard 26 smaller cubes. When the puzzle is solved it has six faces, each made up of nine small square faces of the same colour.
The cube is produced in parts using injection molding then assembled as this is a cost-effective method of manufacture. A mold is a cavity carved into steel that has the inverse shape of the part that it will be produced. Liquid plastic is put into the mold, which takes on the mold’s shape when it cools.
The Rubik’s cube faces need to be labeled, The labels are made from sheet polypropylene material that is printed with the colors. The printed sheet PP is then laminated with a clear PP protective covering.
The standard Rubik’s cube has sides of about 2.2 in (5.7 cm) per square. Various other sizes have also been produced such as a 1.5 in (3.8 cm) mini cube and a 3.5 in (9 cm) giant cube. While the standard cube is a 3 × 3 × 3 segmentation other types have also been introduced. Some of the more interesting ones include the 2 × 2 × 2 cube, the 4 × 4 × 4 cube and the 5 × 5 × 5 cube.
Most of the plastics used in a Rubik’s cube are thermoplastics. These compounds are rigid, durable, and commonly used with (FDM) and (FFF) printers. The plastics used in the Rubik’s cube are acrylonitrile butadiene styrene (ABS) and nylon. Other plastics that might be used include polypropylene (PP), high impact polystyrene (HIPS), and high density polyethylene (HDPE).
Designing Enclosure on fusion 360
Started with an initial sketch of a cube with dimensions of 23mm by 25mm which represents one of the blocks of the Rubik’s cube. Then extruded the sketch by 8mm to create a 3d model of the cube and finally added fillets for smoother edges.
Then used the built-in rectangular pattern tool which selects the cube created and creates replicas in a pattern which is shown in fig. The base was created first and determined both the length and the width of the model. Once the base was created then using the same tool, I was able to create a pattern which determines the height of the model.
Using the shell tool i was able to remove the unwanted material from the top and base of the model and create a wall thickness of 2mm. Once the shell is created for both components i then imported the arduino uno model from the Autodesk gallery, this board along with the dimensions from my earlier research act as a reference to build the pins and rest for the arduino board. The pins where 2.8 mm in diameter and 15mm in height whereas the rest was 4mm in diameter and 4mm in height to slightly raise the board from the base of the model. Finally to make sure the board is sitting in the correct position i used a rigid joint to connect the board to the 2.8mm pin and then to the 4mm rest to ensure the board is not touching the base.
Once the shell of the model was created and the Arduino in the correct possition i was then able to start the cut outs to create both venting and access to ports. I used the sketch projection tool. This allowed me to copy the sketch geometry of the arduino board onto a separate plane. Using these projected sketches i was then able to use the extrude tool to cut sections out of the model to create access to the Power sourse and USB ports as well as all other ports and pins. To create the venting i started with a rectangular pattern sketch of a 1.5mm circle which i then extruded all the way through the top of the model. Further venting is provided by the design of the model which creates a diamond shape cutout between each block which would provide venting all around the PCB.
The section analysis image above highlights a few things. Firstly it shows the PCB raised 4mm above the base and it shows the method of holding the enclosure together. The pin on the base at 2.8 and the pin slots on the top component at 3.2 fasten together to hold the enclosure in place. More importantly also allows the user to access the PCB by gently pulling the top from base, this can be done in less than 60 seconds.
These renders show the final finished Rubik’s model with all cut-outs and full colour to match the famous rubik’s cube design. Also shown is a render of the model in application on a desk to give a better indication of what the model could look like.
Over all I really enjoyed modelling the enclosure for the PCB. I originally found it hard to visualise how i would approach such a design, however with a bit of research into rectangular pattern tool i found a way to create the iconic look of each individual block of the cube while maintaining an inner shell to house the PCB. I found the fusion 360 software to be powerful and easy to use particularity features which allow you to go back in your design time line and make changes to your model. This was useful for this project as i constantly had to make changes to the original block created to change the over all size of the model to meet the specifications of the brief.
Now onto the physical model !
About about Ultimaker.
Ultimaker are a 3D printing company started in 2011 by Siert, Martijn and Erik. They have products such ranging from spare parts and materials to Fuse filament fabrication (FFF) printers. They also offer a free Ultimaker Cura software which prepares your model for 3D printing.
This is Ultimaker’s Original DIY 3D printer kit which you can assemble yourself and offers a build volume of 210 x 210 x 205mm, an open filament system and build speeds up to 8 mm³/s.
Ultimaker 2+ and extended
Ultimaker’s upgraded printer offers to perform difficult 3D printing tasks with ease. These printers have a superior specification to the original as it offers a build volume of up to 223 x 223 x 305, layer resolution from 600 to 20 micron and speeds of 24 mm³/s.
Ultimaker 3 and extended
This pre-assembled printer was Released in 2016 and named best 3D printer by ALL3DP. We have access to these printers at print city which make professional printing more accessible with build volumes of 210 x 210 x 300mm. Also offers dual extrusion capable of creating complex mechanical parts and intricate surfaces and the option to print in two colours.
Ultimaker’s latest printer released in April 2018 which offers more powerful, reliable and versatile printing. This machine has an impressive build volume of 330 x 240 x 300, Fast set up and high up time and easy touch control. Designed to connect it allows print over Wi-Fi or USB and a progress monitoring system via built in camera.
It’s been fascinating to learn about Ultimaker’s printers which use the fuse filament fabrication process which is a process I will use during my master’s study at print city. With printers such as the Ultimaker 3 there is opportunity to create interesting and complex structures through its dual extrusion system which encourages more design creativity and produce better prototype models for presentation.
For this project my task is to design and make a number of 3D printed enclosures for this PCB (Above).
Before the design stage it was critical to do some research into the Arduino Uno to get more information about dimensions of the board. In addition, research was conducted into the toy market as inspiration to to create a design which would would help motivate and educate kids about technology. Some successful brands in this include Lego, barbie, hot wheels and marvel, which aided as inspiration for my ideas. However the brand which suited the aim of my project was Rubiks which was made famous by Ernő Rubik, who was trying to create a 3D mechanism whose parts can be moved independently without the object falling apart, which he could use as a teaching tool.
My second concept was inspired by popular marvel character spider man. The spider sign at the front of the custome is the focal point. This theme could turn what kids might see as a boring arduino enclosure into an object which peaks their interest in technology.
Information about the Arduino UNO board is available from various sources online (fig), I was able to find accurate dimensions of the Arduino UNO board in mm and inches which would act as a reference for my enclosure.
Research into the toy industry
Our first task to get us warmed up is of course to design a tea pot! This task has been used as a beginner exercise in many industries and some software companies even have built in tools to create a teapot. This is a relatively straightforward task to complete but is still fun and is a great way to get started on fusion 360. My aim is to create a design which has traditional features of a teapot but is also unique (see bellow)