Assistive humanoid robot MARKO: development of the neck mechanism Marko Penčić, Maja Čavić, Srđan Savić, Milan Rackov, Branislav Borovac and Zhenli Lu MATEC Web Conf., 121 (2017) 08005 Published online: 09 August 2017 DOI: 10.1051/matecconf/201712108005