  Many have explored the application of continuum robot manipulators for
minimally invasive surgery, and have successfully demonstrated the advantages
their flexible design provides -- with some solutions having reached
commercialisation and clinical practice. However, the usual high complexity and
closed-nature of such designs has traditionally restricted the shared
development of continuum robots across the research area, thus impacting
further progress and the solution of open challenges. In order to close this
gap, this paper introduces ENDO, an open-source 3-segment continuum robot
manipulator with control and actuation mechanism, whose focus is on simplicity,
affordability, and accessibility. This robotic system is fabricated from low
cost off-the-shelf components and rapid prototyping methods, and its
information for implementation (and that of future iterations), including CAD
files and source code, is available to the public on the Open Source Medical
Robots initiative's repository on GitHub
(https://github.com/OpenSourceMedicalRobots), with the control library also
available directly from Arduino. Herein, we present details of the robot design
and control, validate functionality by experimentally evaluating its workspace,
and discuss possible paths for future development.
