Lightcraft Technology | Senior iOS Real Time Engineer | Remote (US) | https://lightcraft.pro/
Hi! I’m the co-founder of Lightcraft Technology. We’re creating a collaborative virtual production platform for the future of visual storytelling. Our team includes deep expertise in robotic systems, real time video processing, and Web frameworks – and a couple of Emmys and Oscars between us!
We’re looking for a senior iOS/real time developer to help craft the next generation of previsualization and on-set filmmaking experiences, where the stage meets the network. You’ll work closely with our small, fast-moving team on leading-edge technologies in augmented reality, rendering, and networking.
This is a product where milliseconds and mathematics matter, and mutexes are a love language. Spin up your xCode profiler, put the pedal to the Metal, and send responses to eliot (at) lightcrafttech.com.
Lead mechanical engineer of the original Roomba here. The article is good on the behavior based algorithmic approach, but equal weight should be given to both the clever sensor design, and the extremely unusual 'passive feedback' cleaning head system the team came up with.
The bump sensor, cliff detection, and wall detection were all implemented with plain IR LED emitter/receiver pairs, and very carefully shaped plastic enclosures so that the sensors provided a binary signal (floor vs. cliff, wall present/absent, etc.) that would hold up for the millions of cycles the machines racked up. This 'filtering in the sensor' simplified the inputs to the 8 bit 8051 microcontroller, and lowered the cost to a couple of cents for each detector.
The cleaning head used the torque of the brush motor to actively control the height of the cleaning head as the machine moved from carpet to hard floors and back. That's the 'core trick' that let the Roomba clean well on multiple surfaces with about 15 watts of brush power. Details in the now-expired patent -- https://patents.google.com/patent/US6883201B2/en.
Dave Nugent came up with the original torque lift idea, and then we worked it into the 'floating pulley' approach used in the final design. It seems obvious now, but at the time this was a radically different approach to mobile cleaning. Everyone else (Electrolux, Karcher, etc.) tried to make a miniature vacuum, but that burned too much power for a mobile system.
Joe Jones (project originator and team physicist) wrote a book about the original team and our development process that I recommend: https://dancingwithroomba.com/
Minor tech notes: Phil Mass did the original programming on the first generation Roomba in C on the aforementioned Winbond 8051 microcontroller. I think it had 256 bytes (!!!) of RAM and 4K of ROM.
The code was burned into the chip at its creation (no onboard flash!) so it had to be right the first time. For the 2nd generation system they ported the behavior code to the internal LISP dialect in use at iRobot.
It was a wild ride. I'm both proud of what we did, and dismayed (but not surprised) at what happened afterwards.
It's hard to appreciate how magical this is until you get beat up by traditional photogrammetry-based set acquisition or trying to build it from scratch in 3D.
In a couple of years you are going to see high school drama groups everywhere staging film productions with this tech.
Hi! I’m the co-founder of Lightcraft Technology. We’re creating a collaborative virtual production platform for the future of visual storytelling. Our team includes deep expertise in robotic systems, real time video processing, and Web frameworks – and a couple of Emmys and Oscars between us!
Our award-winning Jetset iOS app is the core of our real-time connection to cine cameras and stage production. https://apps.apple.com/in/app/lightcraft-jetset/id1634621836
We’re looking for a senior iOS/real time developer to help craft the next generation of previsualization and on-set filmmaking experiences, where the stage meets the network. You’ll work closely with our small, fast-moving team on leading-edge technologies in augmented reality, rendering, and networking.
This is a product where milliseconds and mathematics matter, and mutexes are a love language. Spin up your xCode profiler, put the pedal to the Metal, and send responses to eliot (at) lightcrafttech.com.
Technical details: https://bit.ly/4p3yfpG