Design and analysis of a helicopter landing gear
Brief -
A landing gear is to be designed for a naval helicopter which is suitable for landing on an aircraft carrier. The motion of the aircraft carrier is an important consideration for the design. Vertical movement of the carrier due to the sea waves will cause a harder than expected landing for the pilot and has the potential to cause vibration during storage, therefore the design must allow for this to prevent damage to the helicopter. The design must also cater for diverse landing situations.
You will be provided with some typical data ranges for this type of helicopter, including the mass and some of the dimensions. You will need to find any additional figures you need by research or calculations. The design criteria is deliberately open, it is up to you how many wheels you use and how you model the system in Adams/view. Simulations should be validated with hand calculations where possible.
Tasks -
This is an individual assignment which comprises of four main sections:
1) The first element is to conduct research into the geometry of a typical helicopter landing gear arrangement and design a mechanism to connect the wheels to the fuselage. You should clearly justify the elements of your design.
2) The second element of the task is to specify the springs and dampers used for your particular mechanism. The springs and dampers must allow the helicopter to be able to land on an aircraft carrier under a range of specified conditions:
a. Normal landing - Vertical descent speed of 0.5 m/s, stationary deck, minimal acceleration and oscillations of the helicopter body to provide maximum comfort.
b. Hard landing - Vertical descent speed of 5 m/s, stationary deck, acceleration of the helicopter body must be less than 40 m/s2 to prevent damage to the helicopter.
c. Crash landing - Vertical approach speed 15 m/s, stationary deck, acceleration of the helicopter body must be less than 200 m/s2 to minimise injury to passengers.
3) The third element of the task is to analyse the performance of the helicopter when it is stored on the deck of the aircraft carrier. Assume that the carrier deck will move vertically is simple harmonic with an allowable amplitude and a frequency 1 Hz (6.28 rad/s) in response to the ocean waves, therefore the amplitude and resonance of your mechanism in response to this must be investigated.
4) The fourth element of the task is the modelling and simulation of the landing gear using Adams/view.
Learning outcomes -
This assignment allows you demonstrate the outcomes of the module:
Knowledge and Understanding:
1) Have a systematic understanding of how to model and analyse vibrating systems.
2) Be able to deploy accurately established techniques in order to analyse and synthesise planar and spatial mechanisms.
Abilities:
3) Apply vibration reduction methods to solve problems involving mechanical vibrating systems.
4) Use computer software packages to critically evaluate mechanisms and vibrating systems.
DESIGN & ANALYSIS OF A HELICOPTER LANDING GEAR General advice
Read the assignment brief and the marking scheme carefully!
There is no single correct answer to the assignment; however there are many wrong answers.
The report has maximum 3000 words limit, so you must decide how to present your work in a concise manner.
For example: an A4 page of 12 pt text will contain between 400 and 500 words. If you have a figure on each page, this is reduced to around 250 words, so you would expect to around 12-14 pages at a maximum (not included the appendices).
Split the report into sections e.g. abstract, introduction, design and modelling, results; discussion; conclusions: references etc...
Always using passive voice in writing (third person)
In the Introduction, give the aims and objectives of the work. Describe the project and give some background information (research).
Do not simply copy and paste the assignment brief.
Make reading and marking the report easy - explain the figures, discuss the graphs, etc., don't expect your reader to work them out - they may come to a different conclusion.
Include references in your report (where necessary). These should be listed at the end of the document in the correct format and cross referenced within the document to show the source of the information or specific fact.
Use tables and graphs to display large amounts of information.
Use graphs to compare the results and discuss.
Each figure should have a reference and caption written below the figure.
Likewise, each graph should have a title (written below the figure) and each table should have a table number and caption (written above the table).
If you have included a figure in your report, you must describe it and reference the figure within the text e.g. "The free body diagram in Figure 1 shows...". If you find you have not referenced it in your text, then it wasn't a necessary figure!
How many graphs are required? This is dependent on how you analyse the model. You may wish to present more graphs to show your design iterations.
You will need to justify your choice of design through discussion, calculations and validation with your ADAMS model.
You must perform hand calculations and compare them to the results from your ADAMS model. You do not know your ADAMS model is correct unless you attempt to validate it using calculations. Reports which do not use hand calculations to predict the response will be awarded a lower mark. However, you do not necessarily need to compare every answer.
Attachment:- Assignment Files.rar