This is a laboratory sample rotator designed so that can be used for tumbling as well as gentle mixing of samples in a variety of tube sizes by mixing them horizontally, vertically, or any position in between. Changing the mixing angle is fast and convenient and requires no tools. This device is has an on-board Arduino-based microcontroller incorporated so that adds the functionality of a laboratory sample shaker. These devices can be customized both mechanically and functionally as the user can simply select the operation mode on the switch or alter the code to perform custom experiments. The open source laboratory sample rotator mixer can be built by non-specialists for under US$30 and adding shaking functionality can be done for under $20 more. Thus, these open source devices are technically superior to the proprietary commercial equipment available on the market while saving over 90% of the costs.

For a complete BOM, the code and instructions see main source page and paper here:
* Karankumar C. Dhankani, Joshua M. Pearce. Open Source Laboratory Sample Rotator Mixer and Shaker. ''HardwareX'' 1, pp.1-12 (2017). doi:j.ohx.2016.07.001 open access http://dx.doi.org/10.1016/j.ohx.2016.07.001

This is but one example of how to make an Open Source Lab: http://www.appropedia.org/Open-source_Lab