**1. Introduction**

In medical mechatronics, especially in the minimally invasive surgery (MIS) applications, the design challenge often has multiple sources. However, these

<sup>1</sup> UMAY was supported by Young Investigator Award of Istanbul Technical University (2011–2016) to build a humanoid robot for rehabilitation uses on children with Autism Spectrum Disorders (ASD), supporting the co-authors of this chapter for their PhD.

<sup>2</sup> MEDICARE-C was funded by Alexander von Humboldt Foundation during the Experienced Researcher Fellowship project of Dr. Pınar Boyraz.

difficulties can be generally grouped in relation to mechanism/structural design, actuation selection, and perception. All three fields are affected by the fact that the room for passage, navigation, and operation is very limited. In addition to restrictions in the size of the device, the interaction between the medical device and the tissues or blood poses deeper questions regarding the accuracy of the control and safety of the patient. Regarding the robotic endoscopes/catheters, they can be used as diagnosis tasks using deliberate palpation as well. The other two obvious tasks could include safe navigation inside a narrow and torturous channel while providing adequate accuracy and stiffness at the location of the operation. This chapter presents three different novel approaches which can provide feasible solution to the design challenges while improving the safety. First, in order to improve the mechanical structure and mobility, hyper-redundant mechanisms are presented in Section 2 featuring three different module designs, emphasizing the reconfigurability and modularity. Then, for providing the adjustable forces and compliant action, variable actuator mechanisms are visited in Section 3. The last innovation path involves the perception upgrade, detailing on tactile sensors in Section 4. Involving the tactile sensing units in the robotic skin or sheath can help obtain better feedback and more accurate diagnosis and/or provide safer operation when there are obstacles in the path. All these three aspects are summarized in **Figure 1**.

**Figure 1.**

*An endoscopic robotic platform performing diagnosis, navigation, and operation having a hyper-redundant structure, featured in [1, 2].*
