Project Manager and Technical Lead. Wrote excavator firmware (Python). Designed/fabricated motorization of all levers/pedals, overhead beacon/camera assembly. Performed system-level wiring and integration. Edited movie (and filmed half of footage).

Popular Science Article

ZDNET Article

Gizmodo Article

SF Chronicle Article (Web, Scan and PDF)

ASME Article

Equipment World Article

LifeWire Article

For Construction Pro’s Article

Robotics and Automation News Article

Construction Equipment Article

Assoc. Equipment Manufacturers Article

Heavy Equipment Guide Article

Mechanical design/fabrication, electronics, software*, and robot-filming by Reuben.

*except for stereo camera ROS code by Tony Pratkanis and translation/extension of original Brewer vein-finding MATLAB code into C++ by Aubrey Shapero.

19 mechanical DOFs, 23 optical DOFs, 450 custom part designs, 6 custom PCB designs, 8 microprocessors, 4 DAQ cards, and 20,000 lines of code. Full description of complexity here. 

This movie represents Chapters 4 and 6 from my dissertation at Stanford University, "Improving Peripheral IV Catheterization Through Robotics: From Simple Assistive Devices To a Fully-Autonomous System" (PDF here).

Mechanical design/fabrication, electronics, and software by Reuben.

I created and ran the Automated Testing Lab at Juicero, developing and deploying automated electromechanical systems to 1. test product designs/lifetime for existing and up-and-coming products,  2. support factory manufacturing (e.g. force-vs-motor-current-calibration for every machine), and 3. facilitate and semi-automate data collection during food-science experiments.

Mechanical design/fabrication, electronics, software, and filming by Reuben.

Issued Patent

Washington Post Article

NBC News Article/Video

FOX News TV with Shepard Smith (Tweet after segment)

FOX News TV, “The Greg Gutfeld Show” Discussion

Redbull Article/Interview

Gizmodo Article

abc7 News San Francisco TV/Article/Interview

abc Action News Tampa Bay TV/Article/Interview

The CW WCCB Charlotte TV/Article/Interview

TheShadeRoom Instagram Feature (632K views)

Cheddar Instagram Feature (337K views)

PA Daily Post Article/Interview

IEEE Spectrum Article

DailyMail.co.uk Feature

Korean Channel-A Article/Interview

Digg Feature

Mashable Video Feature

The Dish Feature

TechAcute Feature

Demo at the NEDO/SVR/SRI “Rise of the Robots” event

(link 1 and link 2)

Demo and invited talk at RoboBusiness 2019

Mechanical design/fabrication, electronics, and software by Reuben.

Special thanks to Professor Günter Niemeyer and Benjie Holson for their invaluable advice on the controls-side. You are my controls heroes :)

My dissertation included design and fabrication of HaemoBot, a robot capable of visualizing  and identifying vein bifurcations and inserting an IV catheter into the best vein, completing the entire procedure autonomously. Details of its complexity, as well as the dissertation abstract, can be found here.

Links to PDFs:

Dissertation

Issued Patent, "Remote Center of Motion Mechanism and Method of Use"

Issued Patent, "Assistive Method and Visual-Aid Device For Vascular Needle Insertion"

Mechanical design/fabrication, electronics, and software by Reuben.

Teleoperating (remote controlling) a UR5 arm and Robotiq gripper via Spacemouse to operate a Keurig coffee machine.

https://github.com/Reuben-Brewer/UR5arm_ReubenPython2and3Class

Mechanical design/fabrication, electronics, algorithms, and software* by Reuben.

*Thanks to Aubrey Shapero for translating my original MATLAB bifurcation-finding code into C++ and extending it to 3D point-clouds and to Tony Pratkanis for writing the code that generated those 3D point-clouds from my custom, infrared stereo camera.

This work constituted Chapter 3 of my Dissertation.

Published paper on early Computer Vision work.

Mechanical design/fabrication, electronics, and software by Reuben.

Here is the published paper.

This spherical haptic device was my 3-month class-project for "CS277 Experimental Haptics" at Stanford. It proved that aluminum-on-aluminum friction-differentials could be used to create quality, high-dynamic-range haptic devices, and it used an innovative cable-transmission for the radial DOF.

Mechanical design/fabrication, electronics, software, and clinical-experiment-design by Reuben.

This work constituted Chapter 2 of my Dissertation.

Before we could design a robotic solution to IV insertion, we needed to gain a more thorough understanding of IV insertion itself. Towards this aim, we partnered with the Stanford University Hospital’s Department of Anesthesiology to perform a clinical experiment wherein we recorded video and mechanical data from instrumented needles on IV insertions performed by human practitioners on live human patients. Our broad goals were to answer the following questions:

1. What is the complete list of steps for an IV insertion, including all preparatory, insertion, and post-insertion components?
2. What are the mechanics of human IV insertion (forces, torques, accelerations, motions, and intravenous blood pressure)?
3. Can a human parse data from a real IV insertion to identify the needle and catheter penetration-events into the skin and veins?

The “Nano-needle” insertions used the following sensors:
1. ATI Nano17 6-axis force/torque sensor (on-needle).
2. Tekscan Flexiforce 1-axis piezoresistive force sensor (on-needle).
3. Intravenous blood pressure transducer (off-needle).
4. 3-axis digital accelerometer (on-needle).
5. Motion capture system to measure the 6-DOF motions (markers on-needle, cameras off-needle).
6. Four touch-sensors for manually coding subsections of the insertion (off-needle).
7. Two video cameras, one visible-light and one NIR-light, recording at 30Hz (off-needle).

We intentionally designed the “Nano-needle” to preserve the grasp of a normal, unaltered IV needle, such that the practitioner could grasp it with three or four fingers, left or right-handed. Our “Hook-And-Gap” geometry is what enabled this achievement by allowing the 6-axis force/torque sensor to be placed behind the finger-hold to maintain natural ergonomics while measuring forces as if it was located between the needle and fingers.

Mechanical design/fabrication, electronics, and software by Reuben.

This work constituted Chapter 6 of my Dissertation.

To be able to perform initial testing of my autonomous IV insertion robot, HaemoBot, I needed realistic hand/vein phantoms (not allowed by Stanford to poke myself). I created hardware, software, and fabrication-processes that allowed me to fabricate anatomically-correct, hyper-realistic copies of my own hands and veins.

Mechanical design/fabrication and electronics by Reuben (exception of spiral-capstan-design by Eugene Duval), software by Kevin Loewke.

Here are the published paper and issued patent.

This robot controlled the force between two Neodymium magnets (1 large and 1 small) by inserting plates of a highly-magnetically-permeable material (Hymu-80) in between the magnets to reroute the flux lines that transmit magnetic force. The idea was to use such a system for minimally-invasive procedures wherein a patient would swallow a medical device (e.g. camera pill) attached to a small magnet, and a larger magnet left outside of the body would manipulate the medical device within. Our system proved that closed-loop force-control between two permanent magnets (even with a moving, smaller magnet) is possible.

Mechanical design/fabrication, electronics, and software by Reuben.

This 5-DOF robot wrote sentences in a spiral down the surface of a ball and was my 3-month class-project for "CS225A Experimental Robotics" at Stanford. The robot accepted user-text-input and then generated a trajectory for the marker tip to follow along the ball's surface to write the letters.

It consisted of a custom, prismatic XYZ gantry for translation and a yaw-pitch, mechanical-Remote-Center-of-Motion for rotating about the marker's tip. The marker rode on a magnetically-spring-loaded linear slide to ensure sufficient contact with the ball's surface even with accumulated positional error. 

For this “Fully Balanced” design/prototype, the mechanical design/fabrication, electronics, and software-control were performed by Reuben Brewer at SRI International. Inception Drive inventor and project PI is Alexander Kernbaum.

Patent Application

The Inception Drive is a novel, ultra-compact design for an Infinitely Variable Transmission (IVT) that uses nested-pulleys to adjust the gear ratio between input and output shafts. This video shows the first proof-of-concept prototype for a "Fully Balanced" design, where the spinning masses within the drive are completely balanced to reduce vibration, thereby allowing the drive to operate more efficiently and at higher speeds than achievable on an unbalanced design.

As shown in this video, the Inception Drive can change both the speed and direction of rotation of the output shaft while keeping the direction and speed of the input shaft constant. This ability to adjust speed and direction within such a compact package makes the Inception Drive a compelling choice for machine designers in a wide variety of fields, including robotics, automotive, and renewable-energy generation.

Mechanical design/fabrication, electronics, and software by Reuben.

This work constituted Chapter 5 of my Dissertation.

This chapter sought to distill the best lessons from developing HaemoBot into a simple assistive device, “eye.V.ease”, to help a human practitioner insert IVs more easily and effectively.

Mechanical design/fabrication of field-hardened camera-rig by Reuben.

Movie of hardware in action here.

Terroir.AI uses Computer Vision and Machine Learning to estimate vineyard crop yields. A custom camera-rig is mounted onto the back of a standard ATV and driven along the rows of grapes for imaging, and that data is fed into Machine Learning algorithms to determine ripeness, disease, etc.

Article in WineBusiness.com about Terroir.AI.

Mechanical design/fabrication by Reuben, electronics and software by Morgan Quigley.

Here are the published poster and published paper.

This 7-DOF robot arm was designed to answer two questions: 1. what is the absolutely-least-expensive-design for a robot arm and 2. can inexpensive 3D accelerometers/gyros be used as adequate pose-sensors instead of more-expensive encoders?

Mechanical design/fabrication, electronics, and software by Reuben.

This 15-DOF, 5-fingered, anthropomorphic hand with an underactuated drive-train was my 2nd masters project at Stanford. It consisted of 5 identical fingers with 3-DOF each. The drive-train used only a single, powerful motor at the back and a complicated clutch system with a tiny servo for each finger to select which permutation of joints would be driven at any given time.

Adjunct Lecturer for graduate course “ME223: Applied Robot Design” in Stanford University’s Department of Mechanical Engineering, Fall 2022. This was the second offering of what I originally developed in 2012 as CS235 (switched departments from Computer Science to Mechanical Engineering).

In 2012, I developed and taught "CS235: Applied Robot Design for Non-Robot-Designers" at Stanford University to mostly graduate students. CS235 was born out of my desire for a practical, consolidated, and comprehensive course on building the mechanics of robots so that students don’t have to struggle and waste time teaching themselves these skills. We intentionally selected students with minimal knowledge of mechanical design and hands-on experience to prove that anyone can learn to design and build robots. The best validation? By the end of the course, a visiting CS Ph.D. student with zero mechanical experience had built a 3-DOF haptic device that could touch and feel a virtual environment (video and academic paper). After learning and practicing design and fabrication fundamentals for 7 weeks, each of the nine student teams designed, constructed, and programmed their robot from scratch in three weeks. Five teams created chess-playing robots, and four teams created haptic devices that allow a user to feel real forces in a virtual world. Three of these haptic device projects were the hardware-enabler or subject of academic papers : Forsslund 2015, Menon 2013, and Rotella 2014.

All CS235 lecture, lab, and project-demo videos are available here.

Here is the original course proposal.

Here is a shortened version of the presentation I gave on CS235 at the Stanford CS Faculty Lunch.

Mechanical design/fabrication and electronics by Reuben, software by Morgan Quigley.

This omnidirectional platform was one of my first masters projects at Stanford. The platform consisted of 4 non-holonomic, "steered-and-driven" omniwheels (meaning that they could drive in any new direction only after taking some time to turn/orient to the new direction before moving forward/reverse). Each wheel consisted of 2 independent wheels in a differential-drive configuration with a third, "turret" motor that spun both wheels about the azimuth. This third DOF provided some redundancy/safety in the event that the differential-drive pair lost traction while traversing an obstacle (like an electrical cord or door-jam). This was the proof-of-concept for the Stanford PR1 personal robot, and the same wheel/platform design was later used in the PR2 at Willow Garage.

Mechanical design/fabrication by Reuben.

Fun, 2-day experiment with building snake end-effectors. The top design used a tachometer-cable as the core (stiff in torsion, not in flexure) with laser-cut delrin plates for the body. The bottom design used cast silicone as the core/body.

Mechanical design/fabrication by Reuben.

Mechanical design/fabrication and electronics Reuben.

Motorized lazyboy...No explanation needed.

Mechanical design/fabrication by Reuben.

Junior Year, Undergraduate. These pneumatic stilts were my first self-machined project and took 3-days to design and build over Christmas-break of 2005-2006.

Mechanical design/fabrication and electronics by Reuben.

Junior Year, Undergraduate. This was my very first attempt at building an electromechanical device that wasn't LEGO Mindstorms. I had a $1000 used Subaru that I was happy to modify and a boring summer job that left me wanting to build something on my own.  I pulled a 24-hour build-fest in the JHU ME/EE parking lot. I hadn't been introduced to the concept of an H-bridge yet, so I reversed the drill's direction by using an RC servo to rotate the drill's power wires between two sets of polarity-reversed battery wires. Crude but effective!

Mechanical design/fabrication and electronics by Reuben. Need-finding analysis and testing with other team members.

Undergraduate Senior Design project. Johns Hopkins Applied Physics Laboratory sponsored this project and asked for a way of shooting a special, trackable paint at a car from an aerial vantage point (tracking for law enforcement).

I resorted to testing it on a zipline after the RC helicopter exploded (it hit mechanical resonance due to the extra landing-gear I built for it...)

This page serves to document some of the fun, small projects that don’t fit neatly into other categories.

Sangeet Satpathy (interned with me Fall 2023 - Fall 2024 while a rising senior at Henry M. Gunn High School in Palo Alto, CA). Sangeet developed a mobile robot with a gripper-arm that could drive around an area, use Computer Vision to recognize plastic water bottles, and pick them up for recycling.

Makenzie Fischer (interned with me at SRI International, Summer of 2023, while a rising 2nd-year-Masters student at Stanford University). Makenzie built a Twisted String Actuator (driven by a BLDC and position-sensed with a string-potentiometer) and wrote a PID-controller to issue linear-position commands. Prior to her internship, she aced my ME223 course by making a pancake-flipping robot for her final project.

Mihir Rao (interned with me independently, Summer of 2021, while a rising senior at Henry M. Gunn High School in Palo Alto, CA). Mihir developed a mobile robot for sanitizing high-touch surfaces by spraying isopropyl alcohol.

Claire Du (interned with me at SRI International, Summer of 2021, while a rising sophomore at Stanford University). Claire designed and built a motorized linear slide with a rotating cutter-head that could cut thin sheets of plastic film at high-speed.

Principal Mechatronics Engineer, September 2023 – Present

Performing mechatronic design in the development of robotic and digital solutions to address important cardiovascular needs.

Joe Mullings Video, June 2025 (LinkedIn Post)

Joe Mullings Video, July 2025 (LinkedIn Post)