Mabu - Catalia Health
At Catalia Health, I direct the design, manufacturing, assembly, and supply chain of Mabu. This little robot is the face of the Mabu Care Insights Platform™ that is being developed at Catalia to understand the challenges and journeys chronic illness patients face in the home.
While you can find out more about our company, our mission, and Mabu at our website, I will discuss here the development of the V1 robot, shown in the video above.
Designing Mabu started with the ID model that was created in collaboration with IDEO, shown above. We wanted to create a new and improved spiritual successor to Autom, Cory Kidd's robot from Intuitive Automata, and it needed a design makeover. Our startup-in-residence with IDEO yielded the following result: a much more rounded and (in my opinion) approachable design with a static landscape touchscreen. The robot would still have six degrees of freedom, driven by an Android-powered tablet via custom electronics. But now the robot would be cellular-enabled, and the operation would be simple: just plug her in, and Mabu comes to life.
For the mechanism design, I wanted to keep it very simple for DFM purposes: all motions would use spur gear drive with a small gearmotor, and a rotary potentiometer would track in line with the gearmotor for feedback. (An example of this is shown below.) All parts were designed with manufacturing in mind, with most parts made from ABS plastic with a two-part mold configuration. With the help of Fictiv, we were able to get many of the plastic parts optimized for DFM and DFA, from 3D print to final injection molded part. Using their family-mold process, we were able to get a small set (less than 1000) of plastics for a competitive price; this helped with bringing our BOM cost down. All other parts were either custom machined, or consigned, with emphasis on BOM size reduction.
The electronics were also simplified for cost reduction. Both major PCBA were constrained to two layers, and did not involve much custom design work. The motor control board was a conglomerate of the open-source IOIO board and an assortment of two-channel motor drivers that managed PWM control for the motors, and tracked feedback as analog input to the microcontroller. The board connects to the tablet module via USB serial, and operates in a continuous OTG mode with optimized IOIO firmware for more robust connection to our proprietary app. A small power management board relays power to this board, as well as to the tablet module and embedded hotspot. A push button regulates the on/off function for both the tablet and the embedded hotspot. Originally, the device was programmed to power on once power was plugged in, but complications with hotspot integrations demanded that both be synchronized with the push button for on/off operation.
The tablet module is the main operational component of Mabu. It is an Android OS powered, modified tablet that runs in a kiosk-style mode that only operates our proprietary app. As it is being assembled, Mabu is checked and calibrated using an Android app that I developed, with various modules that check individual components, as well as run a final assembly check for QC assessment and setup. In this process, calibration values are set, a quick burn-in of the motors are performed, and the tablet is configured to connect to its embedded hotspot via WiFi. The tablet originally was designed to use a cellular enabled chipset, but to save on cost and certification time, we opted for embedding a cellular hotspot and leveraging the WiFi for creating a data connection.
V1 of Mabu came with significant challenges, both to constrained mechanism space, cost, and speed. We were able to meet the challenge with many lessons learned, and the development of the Mabu platform continues, as we learn more about the interaction with our current patients, and the capabilities that Mabu can have in future revisions to help in the care of our patients.