When I learned of Professor Nelson's passing I was shocked and deeply saddened. My most sincere condolences to his family. It's taken me some time to find the right words.

I had Professor Nelson in my last semester of college for Robotics class. I remember before the semester had started I was slotted into a 3-hour lab that went with the course that got out at 11pm on Mondays - I told myself I was going to not like it. I remember the first week of class and thinking "Oh god, what have I gotten myself into with this strange class and strange professor". I remember completely forgetting about the first assignment and receiving a 0. I remember the night when everything changed.
I was trudging through the snow to get to the first lab of the semester, night had already fallen and I was so not looking forward to spending 3 hours in a room and then walking back in the cold. I walked into the classroom and there on the table were some decrepit pieces of technology - printers and a VHS player to name a few. Professor Nelson then told us that we were to take apart these "robots" and put them back together in today's lab. My eyebrows raised up. Okay...here it goes. I figured it would be easy as I pulled the VHS player towards me.
I could not have been more wrong. Have you ever taken apart a VHS player? Have you ever even seen the inside of one? I had absolutely no idea what I was doing but the challenge stirred something inside me. I meticulously took apart the robot and was frankly stunned at the beauty I found in it. I asked the Professor questions about this piece and that piece. He answered every single one. I had not even taken apart the whole thing before lab time was up. I, still to this day, have a piece of that old VHS player - the drum that rolls the tape. I often wonder if this exercise was a calculated ploy of Professor Nelson's. Did he know that it was unlikely anyone of us would take the robot apart and put it back together again? I think so and I believe the purpose of that first lab was to inspire wonder, which it exactly did with me. I was hooked.
I came into class the next day with a new sense of purpose. I began to eagerly await lab and class time and I soaked in the information. His class teaching style was different from any other professor I knew. He didn't treat us as students, he treated us as his teammates. His teammates that were going to build a robot with him.
What started out as a sketch on a board turned into a moving, working, living machine. It was called Blob-bot and I love every single step of the process in creating it. I no longer dreaded the labs, instead wishing that they were longer. My first experience with Arduinos, with power tools, and with circuits, were all in his class. Our class was small and soon enough we all became a tight-knit team, all with the goal of creating Blob-Bot. I will never forget the day at the end of the semester where engineering and science students give a poster session to show off their hard work. Blob-bot took to the floor, and even though it was not the fastest robot, there were people all around watching it. I was immensely proud. Looking back, I truly wish I had found Professor Nelson and his classes earlier in my college career as I believe it would have changed what I ended up studying. He opened up the world of hardware to me and I've craved it ever since. And, to take words to action, my current job is quite hardware heavy and I had been wanting to send the professor an email with pictures of what I had been building: "Look what I'm doing now! It's because of you!"

Thank you, Professor Nelson, for helping me find a passion that I never knew I had. You will be sorely missed.

~ Marcelina Martynek - June 21, 2020

I'm so sorry to learn of Randal's passing. We were in junior and senior high together, and I remember him as amazingly intelligent and interested in learning everything he possibly could. I'm sure his children and students benefited hugely from his quest for knowledge. In the past few years we became friends on Facebook, and I was always delighted when Randal would post new photographs. His wonderful eye for a photo was only exceeded by his ability to write a clever, and sometimes wry, caption. I am glad to have known Randal, and wish his family comfort from fond memories.

~ Kevin Bohnenblust - June 20, 2020

Please accept my deepest condolences Gwen, Fiona and Eric.
Randall was a caring man with a sharp wit and easy-going demeanor. I remember him with great fondness, as he engaged in school & scouting activities with our children. His great enthusiasm came through his understated and subtle manner. His smile welcomed and drew in many.
In sympathy, Amy Crossed-Rieck

~ Amy Crossed-Rieck - May 16, 2020

Randal was my colleague (in the Computer Science Department at the University of Rochester), and my friend for 32 years. In the late 80s and early 90s he was instrumental in securing a series of infrastructure grants from the National Science Foundation that laid the foundation for a generation of cutting-edge research. As he transitioned into an increasingly teaching-oriented role, he became the face of the department for graduate recruiting and admissions, and for the assimilation of new PhD students via CSC 400, our "immigration" course. There was no one more dedicated to the department, to his students and colleagues, and to scientific integrity. There was also no pretense: Randal was as candid and honest as anyone I ever met. He was quirky and fun. He loved Halloween. He loved every facet of scientific inquiry. He knew something about pretty much everything, and quite a lot about an amazing fraction of it. He was never ever boring. He was a loyal husband and father, and a steadfast friend. I will miss him very much.

~ Michael Scott - May 9, 2020

Dear Nelson Family,

So sad to hear of the passing of Randal. We have many fond memories of him from Seton and Boy Scouts.

He was a true outdoorsman and had a great love of nature.

He will be missed.

Dan, Mary, Max and Abbie Ferrari

~ Dan Ferrari - May 6, 2020

Randal was the best PhD advisor I could have asked for. The door of his seventh floor office was always open, and he never seemed to mind my interruptions. He always had a new idea I could try when I was stuck, and was always happy to see my successes. He was a gracious coauthor, always acknowledging my work. I took all of this for granted at the time, not realizing how lucky I was.
I haven't seen him for more than 15 years, and I always told myself I would go visit soon. Too late now...
My condolences to the family.

~ Andrea (Selinger) Salgian - May 2, 2020

Dear Gwen, Erik, and Family,
We were so sorry to hear of your sudden loss of Randal. We have very fond memories of Randal and all of you from Seton. God bless you during this very difficult time. Sincerely, Wayne, Linda, Evan and Julie Prentice

~ Linda and Wayne Prentice - April 29, 2020

Randal was a dear colleague at URCS for the past 8+ years, and the instructor from whom I took the Computer Vision course in 1993-1994. It felt like a century ago.

What impressed me the most was his curiosity and critical thinking, and his calmness in the face of his own illness. He also cared deeply about the students, the department, and the university. Over the years, we had arguments as colleagues, especially when serving on the graduate admissions committee together; but nothing was personal from Randal and we respected each other. That was a hallmark of Randal.

I will miss him dearly. My deepest condolence goes to Gwen and the rest of Randal's family and friends.

~ Jiebo Luo - April 29, 2020

I worked with Randal for three short years, in the department of Computer Science, at the University of Rochester. I am so shocked and saddened to hear of his untimely passing. He was always kind, generous with a smile and dedicated to his students. May his family keep his fond memories close to their hearts, where he will remain always. RIP Randal.

~ Michele Schultz - April 29, 2020

My colleague Randal had a varied nature. On one hand, he could speak in a clear-eyed, fear-free way about utterly terrifying health challenges. Yet, somehow along side that, Randal was the most childlike faculty member I have ever known. Not childish, but childlike: endlessly curious about how things worked. Beyond mere curiosity, he was always enthusiastic about finding the answers to how things worked, and he very generously shared with others what he knew (sometimes, in my experience, with actual demonstrations ranging from overlapping colored films to pointing out features on a recently built robot). Probably due to that flame of curiosity, in his too-short time Randal gathered an understanding of science that in its breath and depth was almost beyond belief.

My deepest condolences to his family.

~ Lane Hemaspaandra - April 28, 2020

A great guy, learned so much from him about nature and the outdoors. A lot of great Pack 65 memories. And thank you for the ability to light a campfire like MacGyver! Rest in Peace Randal with one L.
Paul, Davis, and Sarah Hill

~ Paul Hill - April 27, 2020

Gwen and family,
We are so sorry for your loss of Randal and were very saddened to read his obituary in the newspaper today. We have many happy memories of him and your family from Seton and Boy Scouts. Our thoughts and prayers are with you and your family.
Karen and George Morgan

~ Karen Morgan - April 26, 2020

Dear Gwen and family,
We were all deeply saddened to hear of your loss. We all remember Randal from our Seton days and how he was always there to support the kids. We send our love and prayers to all of you.
Sincerely,

Bruce, Pam, EJ, Julia and Kate Baker

~ Pam Baker - April 26, 2020

Randal was one of the most passionate, direct and meticulous people I've ever met.

Being the instructor of an "intro to research" seminar, a course required for all incoming Ph.D. students in Computer Science,
he's touched the lives of many graduate students. Coming from a different country, Randal's classes helped me to quickly get acquainted
with a new and quite different reality. I will always be grateful to him for these lessons.

As the head of the committee for admitting new graduate students, he was always very organized and energetic!
He deeply cared for the department and wanted all events to be a success.
He was never afraid to speak his mind, even if that would not please everyone. I found this aspect of his personality very refreshing.

Our thoughts are with the family in this difficult situation. Randal will be missed, but he will always exist through our memories. May he rest in peace, Spyridoula and Mohammad.

~ Spyridoula Gravani - April 26, 2020

I was greatly saddened by the sudden and premature loss of my esteemed colleague, Randal. He was a creative, incredibly versatile contributor to all our departmental missions and activities, bringing high standards and savvy insights to all he did, along with a great sense of fun---including the performance of satirical songs that brightened our festive occasions.

I was impressed with the scope and depth of Randal's knowledge right from my arrival in 1988. Randal and I were in a lunch group, and at one point the conversation took a turn towards the interpretation of quantum mechanics. I had recently audited a course on the philosophy of quantum mechanics at the University of Alberta, and thought that a tidbit I had learned about the violation of hidden-variable theories by certain quantum-mechanical properties of orthohelium would impress. However, Randal -- whose physics expertise I had little inkling of -- promptly countered with simpler evidence for the same conclusion; and he had a better intuitive grasp of his example than I had of mine!

I also particularly remember Randal's astute questioning of some of our colloquium speakers; we could be sure of our faculty candidates' secure command of their area if they were able to handle "the full Nelson"! Over the years I had many conversations with Randal on topics ranging from AI to politics to cosmic theories. His views were always insightful and often surprising. Whenever I walk down a couple of doors from my own office, I will remember going past his, and seeing the festively decorated and lit-up skeleton looking out at me through the glass partition, long after Halloween or Día de Muertos, and I will miss the chance to chat with him. But most of all, I am saddened by the thought of the hardship Gwen, along with Brendan, Fiona and Erik have had to endure, followed by this tragic loss. I send my deepest sympathy and condolences.

~ Lenhart Schubert - April 25, 2020

Prof. Randal Nelson was my colleague in the department where he was a
long-standing member and I had just joined. Among all my colleagues,
he was clearly the most idiosyncratic -- a skeleton sat in the window
to his office and was always decorated appropriate to the season. He
could appear gruff, but as you got to know him better, you realized it
was an act. He was a principled man and deeply cared about the
undergraduate experience at Rochester. I always looked forward to the
projects his students built during the semester.

He was a fount of knowledge on nearly every topic, and he would
delight both his students and colleagues by his ability to do
"back-of-the-envelope" calculations. The example etched in my memory
is how at the dinner for prospective PhD students, he went on to show
that Rochester was less likely to be affected by global warming or
nuclear warfare -- not a typical dinnertime conversation. But Randal
was not a typical professor.

I was distressed to hear of his affliction -- announced
matter-of-factly by him -- at the beginning of the semester this year, and
was stunned to hear of his passing. I grieve with his family and
friends, and will miss him greatly. My deepest condolences to his
family.

~ Sreepathi Pai - April 25, 2020

Randal and family were always good neighbors. We lost closer touch as our families grew and took us in different directions. So sorry to hear of his so sudden passing. He was a great help with some of the backyard exploits. Wishing peace and comfort to Gwen, Brendon, Fiona and Erik. Please let us know if we can be of any assistance to you. Shalom, Jim and Rita Murphy and family

~ RITA MURPHY - April 24, 2020

Randal was a great neighbor. He was always interested in solving problems and being of assistance. When my garage door wasn’t operating correctly he studied the problem and solved it for me. He helped me put up a long curtain rod that I couldn’t handle myself. Randal and his oldest son Brendan cut down a tree in my backyard for me. He and his two sons helped me move furniture more times than I could count!
Randal and Gwen generously shared beautiful flowers and fresh herbs from the bountiful gardens in their backyard. His nature photography of local parks and by-ways was just beautiful. Randal’s Facebook nature photos introduced me to parks I didn’t even know about right here in the Rochester area!
My sympathies to Gwen, Brendan, Fiona, Erik and the whole family.
With love from a neighbor,
Judy Day

~ Judy Day - April 24, 2020

Randal is among my most trusted and cherished colleagues. I have quoted him in my academic talks around the US and the world of his definition that "science is the art of measurement."

Just three days before he passed away, I asked whether I can quote him the following (in my speech at an award ceremony) where he stated that we at the university are Stewards of Knowledge and compared education with business: "The fundamental currency of a university is knowledge; while that of a corporation is capital. Both traffic information, money, and talented human beings, among other commodities, but the bottom-line metric differs. They serve essential but distinct societal functions.”

He replied my email within two hours:
That would be fine
Pleased to have words remembered!

RN

I will always remember Randal for his wisdom, generosity, songs by the camp fire, and many fond memories!

~ Chen Ding - April 23, 2020

Randal was a dear colleague and friend. He cared deeply about his students, the department, and the university, and has touched the lives of so many generations of our undergraduate and graduate students. He was never afraid to speak his mind. Students and faculty alike benefited from his curiosity, creativity, and wealth of knowledge on every subject imaginable (he was my go to person for advice on all things mechanical). Despite the recent setbacks he and Gwen faced, he poured his energy into all the things he loved the most until his very last second. Randal's warmth and quirky personality were part of the charm that drew me to URCS years ago. I will miss the humanity he brought to all our activities and events. I am sad that we have lost him well before his time. My deepest condolences to you, Gwen, Brendan, Fiona, Erik, and the rest of Randal's family and friends.

~ Sandhya Dwarkadas - April 23, 2020

Randal was one of the most enthusiastic, smart-beyond-imagining, and gentle people I've ever known. I can't believe he's been taken from us so soon. I will particularly miss his cheerful, slightly crooked smile, and his impassioned singing and piano playing with the Algo-Rhythms... My heart goes out to Gwen and the kids; this is wretched beyond imagining. I wish we could get together to celebrate him now... but it will be just as passionate (there's that word again) a gathering when we are able to. Thinking of you all with love and profound sympathy.

~ Suzanne Bell - April 23, 2020