4.1 Motion 

Motion
Motion simulation is a type of simulation which allows you to simulate motion within a 3D model, this allows you to analyse motion within joints and assemblies so that you can ensure that all parts of the model interact in a way which is not unintended and affecting each other.

 Preforming these simulations will allow the engineers to analyse how each part of the model moves in  relation to each other, this is essential especially when designing complex 3D models which require alot of moving parts. 

Collision detection
Collision detection is used  for  detecting when collisions occur  with assemblies or parts, this  makes sure that the  CAD model is designed correctly as the model  cannot contain unintended collisions  as it would cause issues if it moves into being  actually manufactured.

This is used so that the engineer can make sure that no parts, especially moving ones do not collide with eachother. The purpose of this is because if parts are colliding when they are not supposed to it could cause a number of complications such as the device that has been modelled not functioning as intended.

Gears, Drives, Motors or Pulleys
As the name states, this is all about testing motors, gears, drives and pulleys.  This helps as it detects backlash and unsymmetrical gears. 

The reason this is used is so that the engineers can test for issues within mechanical systems like backlash or asymmetrical performance. This is essential especially when designing something like a gearbox for example where accuracy is needed.

Benefits

Starting with benefits, motion simulations firstly save costs and time. This is because to reproduce this testing in real life it requires a real, physical prototype which potentially could be expensive and so making this virtually instead of physically means that costs will be saved on material and time and labor when producing the prototype itself.

This also relates to the fact that when a product is made virtually it is much easier to progress with creating newer, updated iterations of the prototype, this speeds up the entire product development lifecycle.

Doing motion simuations also provides more accurate data from a variety of conditions. This is because, when testing in real life sometimes you are unable to test the prototype in all ways wanted as it isnt feasible, when doing it virtually it has a lot of more options which are readily available.

Drawbacks

Firstly, simulations often require computers with high power specifications which can often be costly as well as requiring a lot of energy to run.  As well as this simulations can often take a long time to be done as they are so computing power heavy, even the most expensive computers can take a while to run some motion simulations. 

Simulations also presume that all factors are perfect, this is such as the materials being in perfect condition and the forces that are applied are exactly what they are. This in most cases does not accurately represent the real life scenario so can lead to virtual simulations being used to get an estimate, and physical simulations to get more accurate results.

4.2 Manufacturability

Draft Analysis:
Draft analysis is a feature which displays to the user the areas of the model which could potentially be difficult to produce when using a mould based manufacturing method. This is done through a sort of colour coding on which areas will be difficult to produce. It can be used to analyse if the draft angles are appropriate and how the overall mould will turn out. If this is not done it could to the mould being incorrect. 

Green is the colour which indicates that the area is easy to manufacture, red is difficult. 

This tool allows the engineers to analyse and evaluate any draft angles that are problematic and will cause issues, this will let them easily and quickly change them.

Mold Flow:
This essentially shows the user how the mould will be filled and what the properties need to be to completely fill the mould, this is all the way from melt temperature to how long the mould itself will actually take to be filled by the material that has been selected. 

As well as just highlighting issues, it also offers possible advice on how the make the mould be filled better and how to optimize the entire process. This makes sure that the engineers mould will be completely full and have a uniform filling.

Tooling Production:
This is a  process which simulates how each tool head will affect the prototype, this assists in the decision making of the user. This is because by being able to see the effect of each tool head it allows the user to narrow down which one they want to choose for their purpose and which will generate them the best results.

This tool will allow the engineer to simulate the tooling processes and let them be able to choose the most efficient ones for their manufacturing process, this will help in reducing errors.

Shrinkage Allowance:
Since materials expand when heated, this allows a preview on what the model will look like and function like when cooled and  shrinkage has taken place.  This is useful as properties of a model may need to be adjusted based on the shrinkage of the model. As well as just shrinkage when models go from hot to cold in a short amount of time it could cause deformities and warping to take place, this feature allows this to be analysed beforehand so that these chances can be removed. If this is not used then it could result in the model when being manufactured to come out deformed, this could lead to a loss of money and time. 

This tool helps the engineer be able to design their model while taking into account the fact that shrinkage will occur. It will better help them choose their materials and make design choices based on the results of the outcomes.

Machining Simulation:
Machining simulation  gives information on how the  model will actually be manufactured. It will give an insight onto  all the properties of the  process such as the filament usage, how long the manufacturing of the model will take  and what the required supports will need to be  to actually manufacture the  model without deformities.  This  can allow the user to  be able to estimate how much filament and time they will need to produce each model.

 This tool is used to give the engineer an estimate on what the material usage  will be as well as  the production time, this also gives the engineer an insight on how they can optimise the machining process and have  produciton outcomes which are consistent

Jig and Fixture Development:
This automatically designs  fixtures as well as jigs which will  assist the manufacturing of the model, this is because these jigs and fixtures are used as a sort of guide within the  machining of the product as well as the cutting. If not done then it could leave alot of room of error for wrong cutting or manufacturing, not only wasting time but also wasting materials as once  a product has been cut wrong it needs to be remade.

This tool  helps the engineer reduce cutting  errors within the  manufacturing process, this once again makes sure that all production outcomes are consistent and precise.

Benefits

This allows the user of the software to modify their design to be able to be manufactured efficiently with minimal material loss, less chance of issues, etc. As well as this, it allows the user to save time and costs due to the fact that by virtually improving on manufacturing it means that no real models are needed to be made to test to see if the manufacturing process is adequate or not. 

As well as just allowing the user to change their design based on manufacturing it also can let the user easily make their choices for the material of the product, this is especially relevant when it comes the analysing the best material to reduce shrinkage which will affect performance. 

Drawbacks
A high power computer is required for these simulations as they are so resource intensive on machines, these high power devices are  extremely expensive and draw a lot of power meaning that there will be high initial costs.

Simulations are not always accurate as well, these could not properly represent all factors of the manufacturing process and result in errors being made due to there not being consideration  of the affecting factors not being perfect conditions  as the  software will presume.

Software is not always compatible with the machines you are using so you often have to pay for multiple software packages, which becomes expensive and means you may need to spend more time and money on staff training to ensure they know how to use the different programs.

4.3 Finite Element Analysis (FEA)

Loads/Forces Applied to Components:

This  is similar to the pressure feature although instead of it being pressure it  gives an  analysis on how different affect  the model , this can allow the user to test from different levels of forces to where the force is affecting and even which direction the force is coming from. This can let the user detect weak spots in the design of the component as well as how the design will respond to these forces from different angles. This is very important in models which are being made of products that require forces to act quite often on them (such as a hammer for example).

This tool  provides the engineer with the ability to simulate how forces impact the model, easily giving them an insight on how to improve their design so that their model is durable and has the correct performance under the expected forces.

Torsional Testing of Components:
Once again, this feature is similar to the last two. This is because it allows the user to test how torsional forces will affect the components, this once again gives the user alot of options for the strength, where it is affecting and what direction. This will give the user feedback on how their design holds up against the forces and what changes they should make for their model to handle them correctly, based on the testing results.

These simulations allow the engineer to view how different  torsional forces will affect their model. This will influence their design choices as they will be able to make their design based on what twisting forces they expect  it to withstand.

Meshing of Geometry:

This feature essentially creates a mesh version of the model, this mesh version of the model  will  be analysed  for its geometric features such as  having sharp corners, overhangs,  variation of thickness and will provide feedback on how all of these can be improved for better strucutural ridigidty and just for an overall more heavy duty model. This also will give feedback on which parts  of the model are able to bew 3D printed  due to some design features which will not be able to be 3D printed.

 This tool  provides the engineer with  a indepth analysis of the models structural integrity  and  if the model is  manufacturable,  especially for 3D printing.

Benefits:

FEA provides the user with the ability to be able to modify their design based on the feedback of structural flaws from the testing, this will transfer to when the model is produced in the real world and in action. This is because, if this testing is not done and the design is modified the device could end up breaking due to structural integrity issues, wasting materials and time as a new device would be needed to be made.

Doing these tests virtually saves a lot of time as by testing them through simulations it means alot of prototypes arent needed to be made as testing them against forces and pressure would result in needing to test them to their breaking point to fully be able to get results on how the model holds up, this would need a lot of material to be used and a lot of time as work would need to be put into manufacturing a new prototype every time one breaks. 

Drawbacks:
Simulations  of this nature  require high power computers that can cost a lot of money to purchase. As well as this, these computers will draw a lot of power when simulating as the computers components will need more power for a higher performance. This means there will be high initial costs.

Using FEA correctly also requires a lot of training and knowledge. This is because there is alot of settings and properties that need to be set correctly to get an accurate simulations which can properly reflect a simulation which will accurately represent true results. 

As well as these factors, these simulations are not always the same as real life and could poorly reflect the real life results. This is due to the factors affecting not always being perfect.

4.4 Computational Fluid Dynamics (CFD)

Material Flow
Material flow is  simulating how a when during a injection style manufacturing process is taking place, how the material will flow through the model. This is because sometimes with certain designs, it is hard to fully fill a model due to the shape of it. To fix this and reduce the error using material flow will allow the user to see how their model will be made and if there is errors they can fix them before the model is manufactured in real life. 

This reduces the waste of materials as without this you would have to trial and error different designs in real life. 

These simulations make sure that all the moulds are filled completely and also make sure that they are filled in a uniform way so that all outcomes are consistent. 

Fluid Flow
This  is used for analysing how a  model will react in the flow of a fluid and how it will affect the flow of the fluid itself. This is because if you are making a model that deals with fluids it is important to optimise it so that it is more efficient. This is all given in feedback by the  software.  You can see results such as  the flow patterns of the model , the streamlines and  how  dynamic pressure will affect the model.

These simulations help the engineer to optimise their models for situations when they need to interact with fluids, this makes sure that the model performs efficiently. This is especially important in situations like designing pipes, ect.

Thermal Conductivity
This  feature is used for seeing how the  model will react under different temperature conditions, this is done by greating a sort of colour  coded model displaying which areas get especially hot and which areas are cold, this could assist in making material choices or design choices as you may want a model which only gets hot in one spot or one which spreads the heat out all over. 

These simulations allow the engineer to pick the appropriate materials for the correct heat distrubution across the model, this is very important especially for devices that are being made to withstand hot atmospheres.

Aerodynamic Efficiency
This feature  basically simulates how the model will react  with airflow,  the airflow can be set at different speeds and direction. This will mostly be used for models of cars, planes, ect. This is because the design will need to be as efficient as possible so that  slowing factors like drag, etc. are reduced. This comes as a simulation which will place  the model in a virtual environment with 'air' affecting it.

This will allow the user to optimise their model to be more aerodynamic so that they could possibly increase the speed or efficiency, etc. 

These simulations will give the engineer the ability to optimise their model to reduce the affects of drag and improve overall performance.

Benefits 

Doing these simulations virtually means that development of the model can be done faster since the improvements can be made at the same time as the simulations are taking place, allowing them to be retested directly afterwards. This overall makes the entire process more efficient as well as faster improvements in the performance. 

As well as this, CFD also provides a very indepth analysis beyond just simple factors such as pressure. By this, it means that the model can be tested for factors which are more relevant such as how well the model can withstand certain temperatures, these are factors which are extremely vital and could take more work and decision making to solve or change for the need of the situation. 

Following on from this, simulating all of these factors is more cost effective due to it being expensive to set up some of these tests. This is because to set up a thermal conductivity test, aerodynamic test, etc. it requires very specific environments and high level monitoring equipment. Instead doing this virtually it can be done with a simple click of a button. 

Drawbacks
Considering these are quite complex simulations, these are very demanding on  the system they are running on. This is unlike basic simulations which although are demanding, are not nearly as demanding as these . This would mean a high spec system is needed which can cost a lot of money up front. Even with this system, it will most likely take a lot of time for these simulations to fully render and complete.

Although these simulations can be used as a guide, real life testing will most likely still need to take place. This is because complex simulations are not always correct, this is due to how difficult they are to reproduce virtually, especially with flow of fluids. This is very similar to how the software will also base the factors affecting from assuming that all conditions are ideal, this is not accurate to reality due to it being very unlikely that all factors are ideal.  

Bibliography: 

Christoff, B.G., Brito-Santana, H., Cardoso, E.L., Abot, J.L. and Tita, V. (2019). ScienceDirect A topology optimization approach used to assess the effect of the matrix impregnation on the effective elastic properties of a unidirectional carbon nanotube bundle composite. Materials Today Proceedings, [online] 8. doi:https://doi.org/10.1016/j.matpr.2019.02.021.

‌Ozdemirel, N.E., Yurttas, G.Y. and Koksal, G. (1996). Computer-Aided Planning and Design of Manufacturing Simulation Experiments. SIMULATION, 67(3), pp.171–191. doi:https://doi.org/10.1177/003754979606700304.

‌

Tut, V., A. Tulcan, Cosma, C. and I. Șerban (2017). Application of CAD / CAM / FEA , reverse engineering and rapid prototyping in manufacturing industry. [online] Available at: https://www.semanticscholar.org/paper/Application-of-CAD-CAM-FEA-%2C-reverse-engineering-in-Tut-Tulcan/ee0b94f98a2a4621811cf017c52babb5802abd59 [Accessed 27 Feb. 2025].

‌

K. Wijesooriya, Damith Mohotti, Lee, C.-K. and Mendis, P. (2023). A technical review of computational fluid dynamics (CFD) applications on wind design of tall buildings and structures: Past, present and future. A technical review of computational fluid dynamics (CFD) applications on wind design of tall buildings and structures: Past, present and future, pp.106828–106828. doi:https://doi.org/10.1016/j.jobe.2023.106828.

‌