Dr. Pain is a Reader in Biomechanics at Loughborough University, Leicestershire, United Kingdom. His 30 yr. martial arts training undoubtedly helped in the creation of a martial arts kicking robot, which aims to faithfully replicate the roundhouse kick in Taekwondo. It was developed along with Dr. Felix Tsui, also at Loughborough. 
Their paper, ‘Utilising human performance criteria and computer simulation to design a martial arts kicking robot with increased biofidelity’ in: Proceedings of the Institution of Mechanical Engineers, part p-Journal of Sports Engineering and Technology, 226(P3-4), pp.244-252 – explores how much damage a (human) roundhouse kick can do, and whether a robot can successfully deliver such a kick. It concludes :
“Multi-segment mechanical impactors can be simple yet still replicate complex human movement, such as a roundhouse kick in Taekwondo. Using simple segments and joints, data in the flexion–extension axis can be evaluated to obtain the key components of the impact. At three kick velocities (12.0, 14.0, 16.0ms21), a multisegment mathematical model was able to match the coordination of the knee and ankle at impact, producing linear velocities (as a percentage of impact velocity) at the knee (8.4%) and ankle (44.8%) which were close to human performance (7% and 47%, respectively). Moreover, introducing additional segments was able to reduce maximum stress concentrations in the impactor by ; 68%, allowing for future development. Properly addressing the coordination and masses of an impactor could help to improve upon the future design of PPE to allow evaluations to be conducted more closely to competition conditions.”
For more info, see Dr.Tsui’s thesis ‘Determining impact intensities in contact sports’