Individual Assignment

Manufacturing of Soft Robotics

I decided to use thonny to replicate a softrobotic grip. I look for some information in different web pages. I found thissoft robotic toolkit page that brings different softrobotics tools, resulting in a series of elements and explanations develop for different projects. I decided to explore how to develop soft robotic actuartors:

  1. I choose PneuNets Bending Actuators
  2. Anderson Zelarayan also used this web page first, so I decided to look for a similar actuator, but with four (04) arms
  3. The limitation for our project was to limited access to electroninc sensors
  4. Our instructor suggest to develop a neumatic system using a 50ml syringe, that was available within the FabAcademy inventory
  5. I needed to build a neumatic system, so I look for some medical supplies that I could use
  6. I choose two different products:
    • 01 Venoclysis System (fig A) that cost $0.5
    • 01 Administration System for Enteral Pump for Tube Feeding (figure B) that cost $9
  7. Then, we need to focus on developing the actuator
  8. I looked for a gripper that could be useful to hold different kind of things. I found a web page with a blog call Why Use a Robot Gripper with 3 Fingers? by Mathieu Bélanger-Barrette
    9. uploaded in 2015 and updated in 2016. This blog brings comparissons between different kind (desings) of robot grippers, base on performance and flexibility. It recommend the use of 3 finger grippers (also call as self-centering). This one could be actuated by hydraulic or pneumatic energy, and because the comparisson is made about robotic grippers it says that the finger could be not so flexible and they probably need to be changed according to the type of object to be lifted. This kind of model could be used to lift different objects sizes and shapes. Thus I decided to look for grippers models with three fingers that could be 3D desing and fabricated.
  9. Further, I found this project at by Fabian Veile - @FabianVeile at printables web page. The project is called Soft Robotic Gripper with Exoskeleton
  10. I downloaded the files, and printed a first version for testing this was printed locating the mold base at the 3D printer's X axis
  11. I decided to replicate this model and design it using fusion 360. I measuare the two main parts and desing both, I made same small changes using fillet function. The following photos resume the process
  12. I decided to follow molding and casting week process to profuce the gripper
  13. We used Resine F-20 that requires Component A and B at a relantionship of 100/3
  14. The process requires to generate the first part of the mold using 4 3D printed parts
  15. The first result was good, like shown in the following image
  16. The first result was good, like shown in the following image, so I run the second step, that was to pour off a second layer of resin to enclosed the grip (figure A). Thus, I used a acryllic base to locate the first part of the grip. However I did not consider superficial tension phenomena. Hence the resin fill into the grip's channels, blocking the air (Figure B) like shown in the image below:
  17. The other problem was that the 3D printed mold broke during the disemsamble process. Thus, I need to change the mold position for 3D printing it, to avoid losing the mold during the process, like shown in the photo below
  18. With the 2nd mold I generated a new grip, and pour off a second enclose resin layer, in this case I pour off a slimer layer of resin, like shown in the photo below
  19. We tested the grip functioning by connecting the air system

  20. I decided to test the grip using a semi-sphere object

  21. Finally, I decided to test the grip with 100gr weigth

    22. You can download the original 3D printing fileshere.

    You can also download my modified version designed on fusion 360here.