INTERVIEW-10

SECURE METER

Name

Shambhavi Mulgaonkar

Branch

Electrical

College

Sardar Patel College of Engineering

Company

Secure Meters

Month and year of interview

10/13/2015

Hardness Level of Interview

6

Company profile

The company is a pioneer for meters and metering solutions in India. It helps monitor and report consumption so that we can use energy more efficiently and responsibly. It is a core job (Marketing profile).

Secure Meters has won the European Smart Metering and Smart grid award for data management and solutions for the year 2015. Corporate responsibilities are done through foundations like 'Dharohar' and 'Khoj'. Its head office is in Udaipur. But it has branches in Mumbai, Gurgaon as well as abroad.

Group Discussion Topic

Group Discussion was completely different. We were given small topics on which we had to answer in one or five lines, concisely and precisely. This was to test how quick and smart we are. 

Then we were given various topics to discuss like- 'Is Mumbai safe for women to travel at night?', 

'Should freshers opt for a job or higher studies?', and so on. All the questions and topics were HR questions in disguise. 

  The sooner you understood that, the better you could formulate your answers.

Technical Round

One technical round was face-to-face. 

Questions regarding:

1. Basic vector analysis, 
2. Three phase power and measurement, 
3. Vector diagrams, 
4. Harmonics, 
5. Single line diagram, 
6. Basic machines, 
7. Power electronics questions 
8. and random questions like what circuit is used for a fan regulator, etc were asked. 

In the video interview (via Skype) ,

I was asked working of Induction motor, and in depth questions related to my BE project. I was also asked general questions regarding upcoming trends in smart grid and power sector.

HR round

HR round was basically were I live, my family background and my interests. 

Further they asked me if I was open to travel since the job offered was sales and marketing. They also asked how I will talk to new people, will I be interested in laying a foundation for their social causes here in Mumbai. They also showed me my technical and general aptitude answer sheets and asked me why I had answered certain questions in a certain manner, etc. They asked me if i was interested in further education, whether i would continue with Secure Meters for a good period of time and also in depth about my hobbies and my thought over various social causes to a great extent. We were also asked to write a feedback for the entire process they had held over a period of two days. 

Later, after I was selected, they informed me that i would be given a knowledge up-gradation schedule and training for two months in Udaipur.

Any advice

Be extremely honest and down to earth. Try to gauge the reason and logic behind every question and never contradict yourself. Be clear in what you know and what you don't and be upfront about. Since it was a marketing position for a core company, you need to have both technical and soft skills. Don't brag. These were very honest people and they expect the same from you. 
Be ready to travel or relocate, such opportunities are hard to find with a rigid set of mind. Try to show them that you can be an asset and bring something new to the table. Confidence is everything! All the best!

Implementation Analysis-Seed Sowing Robot

Preparing  the  Arena        

Design Analysis

Q-1      How will you detect the holes using the sensors available to you in  the kit?     
   We will be using the following sensors for detection of holes :

·         SHARP IR RANGE SENSORS(GP2D120) INTRODUCTION:

We are using the sharp IR range sensors GP2D120. The Sharp GP2D12 infrared ranger is able to continuously measure the distance to an object. The usable range is 10 cm to 80 cm. The device generates an analog voltage that is a function of range, and the output voltage can be measured by an analog-to-digital (ADC) input line on fire bird 5.

How it works

The device emits a pulsed infrared beam at a wavelength of 850 nm ± 70 nm. If an object is within range and in line with the IR beam, reflected light forms an image on a linear CCD  array in the receiver.

Triangulation is then used to determine range. Readings are updated at a rate of approximately 24 Hz. The detector is relatively insensitive to ambient lighting, as well as reflectivity of the object being detected. It is possible to detect relatively dark objects in full sunlight.

The output voltage is a nonlinear function of the distance from the object to the receiver. In figure 1, the curve of voltage vs. distance was taken from Sharp documentation.

**Note that objects less than 10 cm away can look like objects at longer distances. This ambiguity needs to be taken into account if objects are allowed to be closer than the 10 cm threshold.

Triangulation Method:

In trigonometry and geometry, triangulation is the process of determining the location of a point by measuring angle to it from known points at either end of a fixed baseline, rather than measuring distances to the point directly. The point can then be fixed as the third point of a triangle with one known side and two known angles.

The figure 2 shows the principle of triangulation method used in sharp sensors to calculate distance from the object

Q-2            Draw a labeled diagram to explain how you have planned to place the sensors on/around  the  robot? (15)

We are using only the two sharp IR range sensors provided in the kit for detection of hole. The figures 3 and 4 accurately determine the position of the two sharp sensors with respect to the arena and the position of the robot

JUSTIFICATION:

We have decided to place the sensors in the position shown above ,because it will help us detect the hole with great accuracy and prevent us from missing any hole .The sharp sensors have been adjusted in our arrangement at a height, such that it gives a great variation of output analog voltage when it moves from the thermocol surface towards  a hole

.This output analog voltage is then feed to the respective ADC converters which gives the approximate distance of the surface from the sharp sensor.(*in our arrangement ,a value less than 85 represents the presence of the thermocol surface underneath and is indicated by a digital value 0, will a value returned by sharp sensor above 120 represents a hole and is indicated by a digital value 1.Thus whenever the value of the sensor goes from 0 to 1 it represents the presence of the hole underneath.)

DIFFICULTIES:

We had to place the sensor in such a way that the surface is always at a distance more than 10 cm ,as we have discussed earlier that objects at a distance closer than 10 cm  can cause problem .

Q-3      Teams have to prepare the dispenser mechanism for dropping seeds into the holes.

a)      Choose an option you would like to use to position the dispenser mechanism on the robot.          (5)

1.     Front           2.     Back                       3.     Right/Left                   4.   On both sides

Answer: On both sides

**We have placed our mechanism at the center of the robot and have drawn to pipes, such that they are exactly over the left and right whole .thus we have selected the 4 option.

We would be placing the dispenser mechanism on the robot as shown in the figure 5

a) Draw a diagram to show the dispenser mechanism and how it is mounted  on the  robot.    (15)

The following figure determines the position of our designed mechanism for dispensing seeds one by one. We decided to mount our mechanism in the position shown after taking into consideration the following factors:

JUSTIFICATION:

We decided to place the mechanism on both sides of the robot such that the robot does not needs to deviate from the line. Thus the robot can remain in its position and can sow the seeds in the intended hole, preventing any error or confusion due to deviation from the line.

Other factors considered to decide the position of the mechanism:

·         Weight balancing :

Initially we had decided to place two storage and dispensing mechanism on both sides of the robot i.e. left and right, but taking into consideration the weight balancing of the robot we decided to use a single storage and dispensing mechanism such that the overall weight of the robot is balanced and took out two outlets from the it one for sowing seed in the left and the other for sowing in the right hole as shown in the figure 5.Besides this it also provides one more advantage that ,the overall load on the motor is reduced thereby reducing the current drawn by the motor.

·         Ease of mobility:

As discussed earlier we changed our plan of using 2 storage and dispensing mechanism, because it also brought a large amount of constraint on the motion of the robot. Thus reducing the ease with which the robot can move around the arena.

·        Stability of the structure:

Figure 5

WORKING:

Our mechanism consists of three major sections:

·         Seed Storage unit: The storage unit is basically used to store the seeds required for sowing .The unit is designed to store a maximum of 88 seeds .it consists of 8 tubular cylinders separated by 45 degrees , each tube having a capacity to store 11 seeds each as shown in the figure .it is always stationary.

·         Temporary Single seed separation unit:

It basically consist of two parts .one part consists of two disk 1 and 2 as shown in  the figure which are coupled together and are connected to the stepper motor .in between this two disk is another storage unit as above but has the capacity to hold only one seed at  a  time  .the  disk  1  and  2  each  have  a  single  hole  in  them  along  the  rim  of  the  disks

,separated by 45 degrees .the upper disk has a hole 45 degree ahead of the hole in the  lower disk. the hole in the disk 1 allows a seed to come in the single seed storage unit , when it is rotated by 45 degrees the hole in the disk 2 comes directly below the seed and thus the seed finally comes out of the storage unit and is then feed into the dispensing  unit

.this process is continued to drop one seed at a time.

Thus the above mechanism does not allow more then one seed to fall at the same time, preventing any unwanted loss of seed.

Figure 6

·         Dispensing unit: After the seed comes in this unit, it is directed by the servo to the respective hole either left or right. The position of the servo motor is shown in the  figure 7.We have used the servo motor to rotate the flap connected to its shaft a shown in the figure 8.The flap is rotated to decide in which hole does the seed actually go into, which is decided by the program .The figure 9 shown how the seed is diverted towards the left hole by the flap. Similarly the seed can be made to go in the right hole as well.

      FIGURE 7

FIGURE 8

After all of this the seeds are dropped in the hole and the robot moves ahead

Figure 9Q-4  Choose the actuator you will use to design the  dispenser mechanism.                  (5)

1.     DC-Motor        2.   Servo Motor             3.    Stepper   Motor                  4. Others Answer: Stepper motor and servo motor both.

Justify your answer by stating the advantage of the chosen actuator over others. Also give reasons for not using other actuators.

JUSTIFICATION:

We are using both a stepper motor and a servo motor in our overall dispensing mechanism ,but the stepper motor forms an much more integral part of our mechanism .The Stepper motor is used to rotate the disc in our mechanism by a specific angle depending on the number of seeds to be dropped in the hole .We decided to use a stepper motor ,because we required the differentiating disc shown in the figure 6 to be rotated by a complete 360 degree and the servo provided in the kit can rotate only a angle of 180 degrees .

Stepper Advantages:

Stepper motors offer several advantages over servo motors:

·         larger number of poles

·         Easier drive control.

·         The design of the stepper motor provides a constant holding torque without the need for the motor to be powered.

·         The torque of a stepper motor at low speeds is greater than a servo motor of the same size.

·         One of the biggest advantages of stepper motors is their relatively low cost and availability.

Conclusion:

For selecting the best motor for our application, we took into consideration the key design criteria for our system including cost, positional accuracy requirements, torque requirements, drive power availability, and acceleration requirements. Overall, servo motors are best for high speed, low torque applications while stepper motors are better suited for lower acceleration, high holding torque applications.

Thus we decided to use a stepper motor for rotating our disc as it required a high holding torque and their was no need of speed in this application.

Algorithm Analysis

Q-1 Draw a flowchart illustrating the algorithm used to complete the  entire task.          (40) We have divided the overall programs into three sub sections as follows:

·         MAIN

·         LINEFOLLOWER:

In the line follower algorithm below the sensors are represented by the terms left ,right and center respectively .while black and white terms are used to indicate the colour of  the surface.

·         SEED SOWING

MAIN PROGRAM

LINE FOLLOWER FUNCTION

SEED SOWING FUNCTION

INTERVIW-9

EMERSON

Name

Harsh Gosar

Branch

ELECTRICAL

College

SARDAR PATEL COLLEGE OF ENGINEERING

Company

EMERSON Network Power

Month and year of interview

12/11/2015

Company profile

Emerson Network Power is core company. Emerson Network Power – a business of Emerson Electric Company. It is a provider of critical infrastructure, developer and manufacturer of power, thermal and IT management systems, unified infrastructure, software and life-cycle services for original equipment manufacturers, telecommunications service providers, data center professionals, health care IT managers, and industrial facility managers.

Hardness Level of Interview(On scale of 10)

5

Group Discussion Topic

Hon-able prime minister Modi's performance till now

Technical Round

SUBJECTIVE Knowledge:

1. Asked about Semester 6 and 7 subjects. Enlisted Sem 6 subjects and interviewer asked favorite  subject. I told first favorite subject as POWER ELECTRONICS.

2. Asked about different electronics components e.g. Diode, BJT, SCR, TRIAC, DIAC etc.

3. Asked to draw detailed construction of SCR.

4. Detailed working of SCR.

5. Application of SCR- Both rectifier and inverter.

6. Working and graph of full wave rectifier and filter circuit. 

7. Asked about 2nd favorite subject. I told Micro-controller and its application.

8. Asked about which micro-controller you used apart from 8051, I told ATmega328P

9. Asked where this micro- controller is used, I told about its use in our project.

Project work:
1. Asked about project in detail. My project was on RFID based library system so I explained the same.

Participation in competitions:
1. Asked about robotics competition in detail including all the technical things.

HR round

1. Basic questions about family 

2. hobbies

3. extra-curricular activities

Any advice

Stay calm, they are fun loving person. Emerson company came to my campus for the first time (they mostly recruit from NITs).