Announcement of Intent to Compete for Gada Prize
For now this is our announcement of our intent to begin a design which will be entered for the Gada Challenge.
In accordance with the Gada Challenge rules, we are documenting this project on this Wiki, and will be posting all information here, as well as in our own blogs on 
Our design will be a pyramidal structure, with a Delta manipulator built from the top down. The print bed will be stationary, and the delta manipulator will carry a mobile print head. Multi-material printing will likely be achieved by either multiple bowden style heads, or by interchangable tools which can be swapped by the manipulator.
We will be building the electronics from scratch, and using a simplified linear actuator model using inexpensive DC Brushless motors for motion control. The entire control system will have constant realtime absolute positional feedback and a closed PID control loop for motion control as well as thermal control.
One feature we will be building into the electronics are hard failsafe states, for motion and thermal, providing hard protection in the event of firmware malfunction.
The project is in it's early infancy right now, more information will be posted here as we develop it.
3rd party credit
- Ottawa Mini Maker Faire, for inspring me to go ahead with this.
- Rob Gilson, and Hacklab.to for inspiring me to go ahead with the delta manipulator design, with their prototype delta robot they had at the 2010 Ottawa Maker Faire. (Although my overall machine design will be significantly different, the idea to use a delta manipulator generally came from them)
- My wife, Andrea Mumby, for being supportive of this work, including the insane amounts of time and money I've invested into it.
- If I've missed you, I'm sorry, This is a quick post, but I'm sure there are more to come, so to be expanded later.
Features/Goals & Current State
Solid Model Files
This is a simple list for now, very 10,000 foot view. Will refine as we work through the various stages.
- Finish Round 1 Prototype Designs - WE ARE HERE
- Print Round 1 Prototypes
- Assemble Round 1 Prototype Machine, and Test it.
- Design Round 1 Electronics Prototypes
- Build Round 1 Electronics Prototypes
- Begin initial basic control firmware for Round 1 Electronics
- Test Round 1 machine under power.
- Revise Prototype Designs for Round 2
- Print & Test Round 2 Prototypes.
- If test is successful, then publish designs on wiki
- If unsuccessful, then iterate again.
- Finalize control systems for actual use (including writing gcode interpreter and so on).
- Begin work on Extruder Design, and testing actual print capability (single extruder)
- After getting basic printing ability up to par with current RepRap quality levels, then move onto new feature development:
- Automated Build Platform
- Multi-Material Printing
- PCB Manufacturing
- Research into Conductive Thermoplastics
- Pick & Place Grasper Possibility
- Other Developments
- First Beta Prototype of the finished machine designed built at this point
- Final testing, revisions, and adjustments
- Finalization of the design - END GOAL
- While this will be borrowing several ideas from RepRap, the end result is this will likely be a fairly radical departure from existing reprap designs. We will be redesigning and rebuilding almost every component from the ground up, while borrowing inspiration, and ideas from existing reprap development, and building on the lessons learned already which are floating around in the community.
- Initial prototype will have single print-head only. Will look at multi-material printing later, once we have basic printing capability.
- We are considering using modified RC Servos for motion control... These may not offer the resolution we seek, but if we can make the modifications easily enough, they will be far less expensive, and easy to source. If this fails, we will fall back to our original idea of building our own linear actuators from DC Motors.
Nov 8th 2010
- William Harding Joined the team
Nov 13th 2010
- Building up basic plan
- Building on existing ideas, and fleshing out our design goals
- Beginning prototype design for mechanical parts.
Nov 17th 2010
- Prototype designs for Delta mechanics are nearly finished. Need to complete a few more parts before we can print/test a first round prototype. Will post designs shortly once we have finalized them.
- Seeking additional sources of funding/assistance to push the project forward at a more rapid pace. More on this later.
- Servos for the prototype are ordered.
Nov 27th/28th 2010
- Finally got some work done printing and assembling first round prototypes.
- Had to redesign the frame vertices, and the Servo Plate.
- Printed the vertices, and assembled the first round prototype of the pyramid! (pics soon)
- Printed the servo plate parts, and began mounting them.
- Should be able to finalize the STL files shortly, at which time I'll post the current revision here.
Feb 9th 2011
- Had a really rough couple months, haven't been able to get much work done.
- Did manage to get the final design for the universal joints done, and the first segment of the arm is built.
- Need to source a few more bearings before final assembly of the basic robot.
- Once remaining design files are finalized (as in printed, and confirmed at least mostly functional) I will release them here, and on thingiverse.
- Discovered the PolyBot today on thingiverse, been so busy was unable to check in lately. Interestingly they have nearly the same design plan as I do, although their robot is more complete, and their particular goals are slightly different.