For various experimental applications, microbial cultures at defined, constant densities are highly advantageous over simple batch cultures. That’s where a turbidostat comes in, which keeps a culture at a constant turbidity. Here’s a paper by Stefan Hoffmann, Christian Wohltat, Kristian Müller and Katja Arndt where they present a 3D printed small-scale turbidostat for under half a […]
With up to 4 watts of laser power, the Emblaser is comes as a kit for as low as $650. For five times the cost, and with ten times the power, you can get a “hobby series” laser cutter from Full Spectrum Laser. Of course consider if you really need or want a laser cutter, […]
An anonymous contributor wrote in about making laser shutters using hard disk drive rotary voice-coil actuators. The contributor’s lab has made a couple of these which are controlled via an Arduino, at a much lower cost than shutters from Thorlabs or similar. Another paper of a similar vein, by W. Bowden, R. Hill, G. Baird, and P. […]
The general base line solution to spectrometers is Ocean Optics. While bare bones and well known, it’s by no means cheap and the software is propriatary. Consider the Spectruino, at only half a grand and with open source software. Have you tried the Spectruino? We’d love to know your thoughts. The cheapest solution we know […]
The EyeWriter is a DIY low-cost eye-tracking apparatus + custom software that allows people to draw using only their eyes. Eye tracking solutions generally cost upwards of ten grand, but this is just $200 in parts.