Rigid body modes in modal analysis | NX Nastran FEA

Rigid Body Modes 

The model or part of the model may be displaced without stress if it is not sufficiently constrained. These stress-free displacements are called rigid-body modes. If your model is unconstrained in the FEA simulatiion, the first six modes of your solution will be the rigid-body modes

We can define the frequency tolerance under which NX Nastran considers a mode to be a rigid-body mode in its damping calculations. For example, if you define this tolerance value at 0.001 Hz, the modes generated up to this frequency are considered to be rigid-body modes and are excluded from damping calculations. 

1. In the Solution dialog box (when creating or editing the SOL 103 – Response Simulation solution), expand the SOL 103 – Response Simulation group.
2. In the Rigid Body Modes Below box, enter the frequency below which NX Nastran should consider modes to be rigid-body modes. The solve excludes these rigid-body modes from modal damping calculations. If you leave this value blank, the solver uses a value of 10–3 for the tolerance.
3. Click OK.

To Cut micro sim and nano sim from normal SIM| Airtel Smart SIM

Nowadays new smartphones are coming with either Micro SIM slot or nano SIM slot which requires the smartphone users to swap or cut their normal SIM into Micro or Nano SIM.
Method 1 and 3 is applicable to all Networks. Smart SIM option is available for only few networks.

Method 1: Using Micro or Nano SIM cutter 

The most preferred, Cheapest and quickest option is to make your normal SIM card into Micro SIM using Micro SIM cutter

• Go to any mobile service center. Even a small cell phone service center will provide this service.
• Tell them whether you need to convert your SIM into Micro SIM or Nano SIM. Only Apple iPhones require nano SIM . All other latest smartphones need Micro SIM.
• They will have a ready-made micro / nano SIM cutter which looks similar to a classic punching machine.
• The service person will place the SIM in the respective die and cut your SIM into Micro or Nano SIM within a few seconds.
• You can now happily put your Micro or Nano SIM into your new Smartphone and start using it as usual.

Method 2: New Smart SIM card request.

• Nowadays Airtel started to provided Smart SIM option on request.
• Smart SIM consists of the card holder which consists of a nano Sized sim and additional extension adapters of Micro SIM and normal SIM. You can easily swap into any size just by attaching or detaching the suitable extensions.
• The new Airtel Smart SIM card can be requested in all Airtel Showrooms and service centres. The Smart SIM may cost few rupees based on the network.

Method 3: Manual Cutting of Normal SIM to Micro or Nano SIM using scissors

• A risky non-recommended method . Because it requires high artistic skill . A slight deviation would result in damage of the SIM card.
• You have to download the template of Micro or nano SIM in original scale and take a print out.
• Mark it in your SIM card and cut using appropriate scissors to get your required SIM size. 

Best Practices for Keeping your online data safe and to protect your privacy

→Do's

Whether it is an email or online net banking or bill payment portal login, Always the password you set

• should contain a minimum of 8 and maximum of 15 characters
• comprise of characters taken from at least 3 of 4 groups, containing
• at least one uppercase character (A-Z)
• at least one lowercase character (a-z)
• at least one number (0-9)
• at least one special character (!, @, #, $, ^, &, *, ~, space)

→Dont's

Your password should NOT be:

• same as your user name or full name
• a word in any language
• containing single quotes (') or double quotes (")
• based on personal information, names of family members, etc.
• difficult to remember

• You could create a password based on a song title, an affirmation, or some other phrase. (e.g., "myLaptop" or better "Atging!", which is short for: "All that glitters is not gold!". (This is an example; start creating your own!) 

• Don't reveal your password :
• over the phone to anyone
• in an email message
• to family members
• to co-workers while on vacation
• in front of others , public place
• on questionnaires or security forms
• with its format (e.g., "my family name")

If you suspect there is some unexpected login for your online account, immediately change your password and if possible inquire the transaction or history of latest activities. 

Finite Element Analysis : Meshing | Basics

Finite Element Analysis : Meshing 

Generally a finite element model consists of a mesh of nodes and elements. In the Meshing task, we shall:

• define the mesh size directly on edges, curves, surfaces, or volumes

• generate one dimensional elements called beam elements on edges and curves

• generate two-dimensional elements, such as thin shell elements, on surfaces or sections

• generate solid, three-dimensional elements in volumes or solid body

The best way to create a mesh is directly on the part's geometry. Finite element model would be associated with the part, so the software updates the mesh to reflect any change to the part. You can also use geometry-based meshes for geometry-based optimization.

There are separate softwares like Hypermesh dedicated only for meshing with many advanced options that makes the meshing task very easy and fast.

If the accuracy and complexity of the FEA analysis requirement is average, then you can go for integrated FEA applications along with CAD software like Catia, NX , Solidedge etx.

But if the mesh model is very huge, then you should opt for an analysis specific software. 

Blue dart tracking status: Need Department Name/Extension Number | Complaint and Solution

Blue dart tracking status: Need Department Name/Extension Number

Severity Type : Medium

Status Description : Your Blue dart Courier has been received at your nearest blue dart hub . But if you have mentioned your office address to get the courier, then blue dart expect you to mention specific department name where you work and your extension number.

Resolution :

• The best option is to wait for one day, after you see this status and not to create any confusion in the process. Because most probably the delivery person will come to your office gate the next day and call to your mobile number .

• If the delivery did not happen even after one day, then call directly to the blue dart office where your courier is now getting struck. You have to tell your waybill number and your name. They may get your additional details to deliver the product.

• The third option is, in worst case if you need the delivery very urgent, then directly go to the blue dart office where your courier is finally struck (as per online tracking information). Tell your waybill number. Show any ID proof and collect you courier.

HD3D tools in NX | NX tutorial - HD3D for synchronous modeling

HD3D in NX

HD3D is a new feature introduced in NX Siemens , that allows you to quickly find an information about the product you design and helps you to diagnose the error or warning that occurs while designing the component by providing sufficient information about the error and warnings.
These information will appear like annotation tags , where the error occurs exactly in the component.

How to Access HD3D tools in NX ?

HD3D tools in NX is avaialbel in resource bar. We can also access this tools using command finder option.

What are all the HD3D tools available in NX?

Visual Reporting tool 

Visual Reporting tool helps you to visulaize information directly on the components / objects inside the graphics window itself.

Check Mate tool

Check mate tool allows you to validate product information.

Product template studio tool

Information related to execution of PTS template can be accessed using Product template studio tool

Requirements validation tool

Manages requirement of a product design.

Issue management tool

Allows you related to issue management.


You can use the HD3D tools to interact visually with information presented in the graphics window that may previously have been presented in dialog box lists and information reports

Trigonometry - Practical Real world applications and Problems in Trigonometry

Trigonometry :

• Trigonometry means Triangle Measurements. (Measurements of triangle)
• Considered as one of the oldest branch of mathametics as it is used since ancient days in the field of astronomy by ancient Indians and Babylonians.
• Historical records show that Babylonians used to divide a circle in 360 parts ,naming it as a degree . Maybe they had divided so, predicting 360 days for an year.
• And Indians discovered and applied sine function around 300 AD.

In modern days, trigonometry is used is real world applications in various fields like Engineering fields, Navigation purposes, Surveying applications etc.

Practical Application of Trigonometry :

1. To buy a new ladder :

A man build a room over his house . His budget is not allowing him to build concrete steps to climb for the new room. So he plans to buy a steel ladder to set up so that he could easily climb the room.
He decides to keep the ladder in 60 degree inclination (between ground and the ladder), for comfortable climbing. The height of the house from ground to first floor is 2.5 meters.
He goes to buy the ladder and the shop owner inquires that, what is the height of the ladder? Now,  what is the appropriate height of the ladder he should buy?

Solution :

Sin 60	= Opposite /Hypotenes
(√3 / 2)	= 2.5 / Hypotenes
Hypotenes	= (2.5 x 2 ) / √3
Hypotenes	= 5 / 1.732
Length of Ladder	= 2.88 meters