Meet the Lynxmotion SES-PRO: a semi-professional modular robotic arm with 550mm reach and 2kg capacity that you can use to build all kinds of complex robots. It has NEMA 17 & 24 motors & strain wave gearing with joints that can be swapped or reoriented. It can be used on a fixed surface or mobile platform.
Lynxmotion SES-PRO 550mm robot arm kit has accuracy of ±0.1 mm. You can add additional degrees of freedom for more complex projects.