From 673d522ad73398201cfd69a9cb959bf8fbeffc2a Mon Sep 17 00:00:00 2001 From: David Preiss <davepreiss@gmail.com> Date: Wed, 21 Jul 2021 16:46:39 +0000 Subject: [PATCH] Update README.md --- README.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/README.md b/README.md index 5578731..650e425 100644 --- a/README.md +++ b/README.md @@ -4,12 +4,12 @@ A 3-axis motion platform designed to minimize moving mass and inertia. Prototyped with the CBA at Haystack in July of 2021. Two prismatic actuators form a 3-bar linkage with adjustable side-lengths, which allows for an addressable XY space formed by the intersection of the two arm's revolved maximum length. -Note that the forward kinematics ignore the axes rotary centers not being coincident with their linear motion (an offset of ~25mm). This should be included before the system is adapted into a project requiring a higher degree of precision. +Note that the forward kinematics ignore the axes rotary centers not being coincident with their linear motion (an offset of ~25mm). This discrepancy should be accounted for before the system is adapted into a project requiring a higher degree of accuracy. -The CAD presented here uses a GT2 timing belt with a fixed NEMA17 stepper mounted to a rotating Z-axis. This belt + motor shuttles a 5/8" carbon fiber tube through custom acetal bushings. Many of the design decisions were based on what was immediately available at Haystack. - -<img src="images/ppaCAD.png" width="700"> +The CAD presented here uses a GT2 timing belt with a fixed NEMA17 stepper mounted to a rotating Z-axis. This belt + motor shuttles a 5/8" carbon fiber tube through custom turned acetal bushings. Many of the design decisions were based on what was immediately available at Haystack / the lab before leaving, so there's plenty of room for optimization left. Two scripts are provided, one which takes the actuator through a canned series of motions forming a rectangle, while the other listens for serial inputs from a MODs toolpath pipleine written by Eyal Perry. Click the picture below to find a video of the setup running. [<img src="images/forestBeing.png" width="500">](https://gitlab.cba.mit.edu/davepreiss/parallel-prismatic-actuator/-/blob/master/images/forestBeing.mp4) + +<img src="images/ppaCAD.png" width="700"> -- GitLab