It’s fascinating how simple / elegant this design is. Although you probably could use machine learning, etc for this a basic optical sensor is ‘good enough’. With all the exciting new tech out there it’s easy to forget that many things can be done much simpler.
"When tomatoes ripen in California, for example, they’re harvested in a 12-week period that has sorters running round the clock, up to 24 hours a day, processing as much as 800 tonnes of vegetables an hour."