Robotic Arm Project V2

Overview

I am working on an upgrade of my Robotic Arm Project that has managed to survive two years worth of kid interactions over the course of many different events. To say I am surprised at its longevity is an understatement.

Project Goals

As with all of my projects, my primary goal is to learn more about electronics, CAD, programming, etc.

For version 2 I will be adding or changing the following items

• Better Base - the previous version had a small base as outlined in this post which had to be attached to a surface. In my case, I screwed it down to a board and mounted the arm, controller and controls to that board. It worked but wasn't at all a finished project. For version 2, I am designing a base enclosure and control interface. 
  
  
• Better Base Support Bearing - In the original project, the arm was supported entirely on the lower servo shaft. Remarkably, this design has lasted for 2 years but it is still very flimsy and makes the arm wobble. So, for the upgrade, I will be using a more robust bearing design.
  
  
• Arduino Controller - The previous design used a programmable servo controller to take inputs and control the arm. It worked pretty well but was limited in the number of inputs and outputs. For version 2 I will be using an Arduino for the controller.
  
  
• Record and Playback - In addition to manual manipulation of the arm, version 2 will be able to record a series of movements and then play them back.
  
  
• Demo Mode - Watching the interaction of people with version 1 taught me that if allowed, people (especially kids) will sit and play with the arm for an hour if you let them. For version 2, I will be adding different modes of operation - one of which will be a demo mode that allows folks to play with the arm for about 1 minute and then shuts down so that the next person will have a chance to play with it. I am planning on having a screen on the arm with a countdown timer that displays that the time is up. I call this Armatron mode after one of my favorite childhood toys.
  
  
• Preset Buttons - I will be adding some buttons that will perform some preset or recorded functions.
  
  
• Aux Control Port - I'd like to make the control options for the arm expandable. I will be adding an I2C connection port so that alternate controllers can be plugged in to control the arm. Examples may include gesture control, PC control, feedback control via third pary system, etc.

Project Timeline

I would like to have this project completed in 4-5 months. I've given myself a deadline of Febuary 28th, 2017.

Project Budget

• My goal is to keep my materials cost below $100.
• Other costs like laser cutting and engraving are not included in this budget as they change based on vendor and location. I use a very reasonable local vendor who does excellent work. 
• I tend to recycle used parts when I can so the ultimate cost may be difficult to follow but when this project is complete, I will as usual post a list of parts and sources that I typically use so that others can build the project if they choose.