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Created August 23, 2018 20:20
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> Why are you interested in this position?
I am a robotics researcher at the University of Pennsylvania and will graduate with a PhD in Electrical Engineering in August. The experience I have gained in both software and hardware robotics engineering are, I think, directly applicable to the mission of Humanistic Robotics, and I'm very interested to apply my skills to make the world a better and safer place.
> Describe your hardware design experience?
I have worked on several projects in college and graduate school that involved hardware design. As part of teams, I helped design a quadrotor UAV and later a handheld visuo-haptic sensor assembly which was modeled in SolidWorks and assembled using laser-cut MDF and 3D-printed acrylic. With my current level of experience, I am much more comfortable on the software side than in mechanical design, but I am looking to gain more experience using tools like SolidWorks.
> What size teams have you worked on in the past?
I have mainly worked on academic research projects, solo or in teams of 2-6 people.
> What is your experience with schematic design?
Each of my engineering design projects throughout college and graduate school have involved schematic design, using PCB Artist and Eagle for schematic capture. This includes a custom audio amplifier with digital volume control and several projects that involved designing a PCB to interface with peripheral sensors. In my thesis research, I modified an existing PCB designw to add more sensor inputs.
> What is your experience with test and characterization of switching power supplies?
I do not have previous experience with switching power supplies, but I am eager to learn!
> What is the difference between single ended and differential signals? Where might one have an advantage over the other?
The difference is in the reference point for the signal. In a single-ended system, there is a "ground" or "common" pin/wire which is taken to be zero, and the other signals are relative to that. On the other hand, differential signals need two pins each, and the measured value is the difference between their voltages. Each has advantages in some situations. A single-ended design obviously uses fewer pins. However, with long wires or very small signals one might choose differential signaling, so that any interference or voltage drift would apply equally to both wires, and get subtracted out. In my thesis project, we use an ATI Mini40 force/torque sensor which outputs strain gage measurements as differential signals, which are then amplified using a differential op-amp before quantization. Those signals can be quite small, so differential amplification is important.
> Which bulb will be brighter? Why?
The top bulb will be brighter. With the bulbs in series, the same amount of current will flow through each, but the top one is designed to dissipate less power, which means its internal resistance is higher, so the voltage drop across it will be higher. At constant current, power is proportional to voltage, so we have more power dissipated across the top bulb.
> How should the circuit be changed so that both bulbs will be as bright as possible given the same 100V source?
Place the bulbs in parallel. Since we're assuming the power source can produce as much current as required, each bulb will draw the current for which it is designed and be brighter than they were in series.
> Describe your ideal job. What would you work on? Who would you work with? *
I would ideally work on a small-to-medium-size team developing interesting technology that has a visible impact in the real world.
> What is your ideal yearly salary and why?
As you know, I'm just coming out of school. I think fair compensation should be settled in an interview after discussing job responsibilities. Based on my research, competitive industry salaries range from $80-100K, which sounds reasonable to me.
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