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Control and Actuation of Eighth-Era Biomachina for Bipedal Gait Synthesis via Aetherochemical Somesthetic Instrumentation

A thesis presented by Athalaric Siegryn
in partial fulfillment of the requirements
for the accreditation of Mastery of Science
in the subject of Ars Arcanima

The complexity of the leg is reflected in the challenges of developing an artificial leg replacement, in particular that of Spoken and other creatures exhibiting a bipedal gait. Although agonist-antagonist actuation mechanics and framework of a bipedal leg can be simplified as a two degree-of-freedom ambulatory mammet actuated at its joints, the control of locomotion is dependent on environmental stimuli. Ambulation requires the intuitive processing of vast amounts of stimuli to inform locomotive intent, then translate intent to motion with negligible processing, but a prosthesis does not have access to the same sensors. Thus, a limitation of prosthetic control is the necessity of sufficient sensory robustness to motivate biomechanically accurate behavior.In pursuit of sensory robustness, characterization of locomotion-relevant stimuli is critical. These stimuli can be categorized by sensory modality. The somatosensory system is comprised of various intrinsic sensory modes for the perception of internal and proximate stimuli. This paper discusses the somesthetic senses of touch, balance, and proprioception, how such sensory stimuli informs locomotive behavior, and how analogous sensors can be implemented in a lower-limb prosthesis.One can begin by considering automata that already exhibit bipedal behavior; the magitek warmachina employed by the Garlean military comes first to mind when considering such examples. The overengineered stability of the walking frame of magitek vanguards and colossi alike can serve as the foundation for the synthesis of bipedal locomotion algorithms, with analogue hydraulics and redundant range of motion being the compensatory factors for addressing common issues to a bipedal gait, such as uneven terrain and balancing readjustment.This methodology is not without its shortcomings, however, as the control schema dictates the only stimuli to modulate the gait cycle be either contact-reactive or user-input, the latter of which has a rigorous ceiling of competence. This limitation in turn dictates the design criteria of the chassis and actuating components, which makes such architecture impractical for the purpose of limb replacement, for which a significantly higher power-to-weight ratio is necessary. Furthermore, when considering bipedal automata, the entirety of the gait cycle is synthesized by the controller - in the instance of limb replacement, however, such a device lacks any innate method to percieve the position and trajectory of the alternate limb [...]