New developments in defecatory studies based on biomechatronics

•The physiology of defecation and the pathophysiology of defecation disorders have been described in numerous studies.•Disagreement exists between results of anorectal tests and they correlate poorly with symptoms.•We tested a novel wireless Fecobionics device, a simulated integrated stool in normal subjects.•Novel analysis of distensibility indices is presented based on preload-afterload diagrams and key parameters describing defecation are derived.•Fecobionics obtained reliable data under physiological conditions. The study suggests that Fecobionics is safe and effective in evaluation of key defecatory parameters.•Novel parameters were generated that may be important for subtyping of patients with anorectal disorders.