My time at Intuitive was packed with myriad projects, each showcasing an important part of an engineer’s day-to-day. From background knowledge, to planning, to building, to measuring, we were able to look at the full scope of the engineering design process and every bit of work that goes into it. It was an illuminating window into engineering careers and definitely piqued my interest as something I’d like to explore in the future.
Plus, I got a cool hat.
Today was my last day at Intuitive Surgical. I spent my morning finishing the nylon 3D print, and analyzing the data from the tests with the PETG 3D prints. In the afternoon I worked on finishing the presentation I would be giving later in the day, and did my final Instron test on the nylon print. This print ended up being my strongest, being able to withstand 210 pounds of force. To wrap up the day I presented my findings from my work over the past two weeks to the engineers at the office.
I had a great experience at Intuitive Surgical over the last two weeks, and would like to thank everyone at Intuitive for hosting me.
Today was the final day of our time at Intuitive. Work continued on the OCT projects as code was rewritten onto Arduinos and registered on signals, which were then observed on the oscilloscope. Meanwhile, more tests were done on 3D printed pieces, and a presentation was given to the mechanical engineers at the office about the design challenge, ideas, and results.
Today I worked on setting up a special 3D printer to print my designs out of carbon fiber nylon. A different 3D printer had to be used to as nylon requires extremely high temperatures to be able to print properly. Once the 11 hour print began, I spent the rest of the day working on CAD- designing an adaptor for their lazar cutter so that it could be hooked up to a ventilation system. Tomorrow the nylon prints will be ready for testing, and I will be able to conclude the project I have been working on for the past two weeks.
3D printer printing the nylon parts:
Today at Intuitive we continued our work on OCT (Optical Coherence Tomography) projects by mapping out multiple paths in python, some of the paths were, a square with n amount of lines, a circle cut up at a certain angle, and an Archimedes spiral with equidistant points by arc length. Calculating the distance of the points on the spiral involved some interesting calculus, especially with the intention to implement it on an Arduino which has far less memory than our computers.
Today we looked at creating a smaller version of an Optical Coherence Tomography machine—a non-invasive device used to create 3D images of tissue, often used for imaging retinas. Among other things, this device requires multiple scanning patterns, all of which are used to produce slightly different images. We implemented these in Python, plotting with matplotlib, in order to verify the correctness of our code. The next step is to put it on an Arduino.
Below: the code producing a scanning pattern approximating an Archimedes spiral. The code had to evenly space dots along the spiral arc, a nontrivial task with limited computing resources—the formula for determining arc length of an Archimedes spiral based on angle is complex and includes slow operations such as the natural log. In addition, we weren’t able to find a closed-form inverse for this function, which is necessary for actually plotting the points. However, we found that a second-order Taylor series provided an surprisingly good approximation and was easily computable and invertible. The code below utilizes the Taylor series and is effectively indistinguishable from a true Archimedes spiral.
Below: Me excitedly explaining the technique.
Today at Intuitive surgical, the morning was spent cleaning up the PETG plastic 3D prints that were printed over the weekend. In the afternoon the PETG designs were tested with the Instron machine (a machine that can apply and measure extremely high on an object in compression or tension). It was found that the PETG designs were slightly weaker overall, compared to the PLA designs previously tested. To wrap up the day I worked on setting up a special 3D printer that is able to print carbon fiber nylon plastic, an extremely strong material that can withstand much higher compressive strengths.
One of the designs being tested:
Today at Intuitive Surgical we finished our investigation into the voltage, current, and temperature of a linear actuator while it is performing work onto differing amounts of mass. Afterwards me began our next and final project: creating a signal generator to facilitate an OCT (Optical Coherence Tomography) solution. OCT is a technique used for creating three dimensional images, such as of retina, by reflecting electromagnetic waves of different frequencies and measuring the phase shift. We also stress-tested some 3D prints in the Instron machine.
Today was more 3D printing, printing out the same designs as yesterday but out of PETG plastic. PETG plastic is a heavier and is a lot stronger the PLA plastic used yesterday. After the 3D printing finishes over the long weekend, the final testing with the instron will be completed. While the parts were 3D printing, I spent my time refining a new CAD design- hoping to fix the flaws of the previous designs.
Today at Intuitive we looked at a real project mirroring the day-to-day work of engineers: measuring! Although engineering is often made out to be largely about design, it’s equally about ensuring that components and assemblies are built up to spec and continue functioning at capacity even under load.
The part we took a look at today was a linear actuator, a device that extends and retracts even when fighting significant force. We measured it loaded with weights and without, and plotted the voltage, current, and temperature over numerous trials.
Below: Overlaid voltage/time graphs for 216 trials.