File:Anthrobots can move across living monolayers in vitro.jpg

English: "A) A representative timelapse video of an Anthrobot as it moves along a neural scratch in vitro. B) Sample tracking video output with scratch edge highlighted in yellow and bot path in red. The rotation of the bot is measured through the change in the orientation of the green and red bars attached to the center of the bot in white. C) The significant (p = 0.017, slope 1.15, n = 17, t-test for slope) positive relationship between bot gyration index and proportion of bot's body in contact with scratch suggest that circular bots cover the edges of the scratch more as they move along the scratch. D) The significant (p = 0.031, slope 0.0082, n = 17, t-test for slope) positive relationship between bot speed and proportion of bot's body in contact with scratch further suggest that faster bots also cover the edges of the scratch more as they move along the scratch. E) For a subset of bots (dataset constrained to non-stalling bots with rotational tendencies between 0.33 and 0.7 and viable tracking videos), the quadratic (alternative curves were insignificant) relationship (p = 0.006, n = 13, t-test) between bot gyration index and scratch-trajectory similarity metric suggests that there is a goldilocks zone for the bot rotational tendency for maximum scratch area exploration. This quadratic relationship was revealed when we initially tested for a linear relationship between these two metrics by plotting the residuals against the fitted values for the model, and observed a clear quadratic trend among the residuals (see Figure S9, Supporting Information), which strongly suggested the fitting of a quadratic model instead, which is shown here. Consistent with these statistical analyses, in the experimental space we observed that bots with very low rotational tendencies interacted minimally with the scar edges while bots with very high rotational tendencies skidded in place or was prone to veering off the scratch edge. There appears to be an optimal amount of rotation for a bot to move across the scratch while faithfully following the scratch edge. "