Date of Award


Document Type

Masters Thesis

Degree Name

M. S.

Organizational Unit

Daniel Felix Ritchie School of Engineering and Computer Science, Mechanical and Materials Engineering

First Advisor

Mohammad H. Mahoor

Second Advisor

Siavash Rezazadeh

Third Advisor

Kimon P. Valavanis

Fourth Advisor

Goncalo Martins

Fifth Advisor

Kerstin Hering


Autism spectrum disorder, Children, Kinematics, Omniwheel, Robotic assisted therapy, Social robot


The continued growth of Autism Spectrum Disorders (ASD) around the world has spurred a growth in new therapeutic methods to increase the positive outcomes of an ASD diagnosis. It has been agreed that the early detection and intervention of ASD disorders leads to greatly increased positive outcomes for individuals living with the disorders. Among these new therapeutic methods, Robot-Assisted Therapy (RAT) has become a hot area of study. Recent works have shown that high functioning ASD children have an affinity for interacting with robots versus humans. It is proposed that this is due to a less complex set of communication modes present in a robotic system as opposed to the complex non-verbal communications present in human to human interactions. As such, the Computer Vision and Robotics Lab at the University of Denver has embarked on developing a social robot for children with ASD.

This thesis presents the design of this social robot; Nyku (Figure 1). It begins with an investigation of what the needs of ASD children are, what existing therapies help with, and what, if any, roles a robot can play in these treatment plans. From the literature examined, it is clear that robots designed specifically for ASD children have a core set of goals, despite the varied nature of the disorder's spectrum. These goals aim to reduce the stress of non-verbal communications that may occur during standard therapies, as well as providing capabilities to reinforce typical areas of weakness in an ASD persons social repertoire, such as posture mimicry and eye contact. A goal of this thesis is to show the methodology behind arriving at these design goals so that future designers may follow and improve upon them.

Nyku's hardware and software design requirements draw from this foundation. Using this "needs first" design methodology allows for informed design such that the final product is actually useful to the ASD population. In this work, the information collected is used to design the mechanical components of Nyku. These elements consist of Nyku's Body, Neck & Head, and Omni-wheel base. As with all robots, the mechanical needs then spawn electronics requirements, which are, in turn, presented. In order to tie these systems together, the control architecture is coded. Notably, this thesis results in a novel kinematic model of a spherical manipulation system present in the Omni-wheel Base. This solution is then presented in detail, along with the testing conducted to ensure the model's accuracy.

To complete the thesis, overall progress on Nyku is highlighted alongside suggestions for a continuation of the work. Here, the engineering work is compared against the design goals which it tries to fulfill in an effort to ensure that the work has stayed on track. In continuation, this examination maps out future steps needed to optimize the engineering work on Nyku for reliable performance during therapeutic sessions. Finally, a therapeutic plan is proposed given the hardware capabilities of Nyku and the needs of ASD children against the background of modern therapeutic methods.

Publication Statement

Copyright is held by the author. User is responsible for all copyright compliance.

Rights Holder

Dan Stephan Stoianovici


Received from ProQuest

File Format




File Size

148 p.


Electrical engineering, Robotics, Computer engineering