6/25 Update
As of now, I still have not received images of the hang robot, so I cant make the CAD model yet.
As of the CAD design process, I have been going through PTC’s “How to Develop a Product” and here is my current learning:
Phase 1 –
- First of the few steps are self explanatory and some of which we have already done. This includes – Creating a project plan table in which we document current tasks for team members and putting on them on a spreadsheet separated by date. They have also talked about using PTC Windchill.
- Here are some future plans that they suggest – Creating a systems requirement table and this includes identifying the scoring options, and the robot functionality required and then the system requirements.
- In PTC Parametric, they talk about using a very rough draft called an envelope in which we create different subsystems. These subsystems are basically the parts of the robot in which we will explain their functionality pertaining to a specific goal.
Phase 2 –
- This stage is quite long specifically for using PTC Parametric and talking about all of its features for calculating things such as density, center of gravity, etc and documenting them down. Currently I am still going over parts of this phase.
Phase 3 –
- This phase is for after the product design is complete.
- It first talks about the importance of assembling a robot design in CAD before actually creating it so that you can identify all of the parts in the product design and create a bill of materials.
- Next is creating a production plan with a spreadsheet. This will separate parts, fabrication, supplier, and date received.
- Something that it also stresses is documenting all the decisions and changes that have been made.
Phase 4 –
- The main topic of this phase is something called FMEA (Failure Modes and Effects Analysis), and it is used to determine why things might fail, and their probability of failing.
- Step 1 – Identifying all the possible ways in which your robot could fail.
- Step 2 – Rank failures in their likeliness to occur, and their effect after failing.
- Step 3 – Address theses failures, and find a solution.
- There are also a few more plans that is suggests – Field Support Plan (Used to prepare parts for the robot in case of failure), and Product Retirement Plan (Disassembly and recycling of parts and materials.)
- Finally it talks about exploded drawing in PTC Parametric, which I am currently working on.
7/23 update (Jerry)
I have finished most of the CAD model. It looks like this:
A few interesting things I learned:
- When assembling different parts together, the 1st piece you assembled has to be default, and when you assemble the 2nd piece, you only see the first piece. But, even after you assemble many pieces, when you try to change the position of the 2nd piece, you still only see the first piece in the screen. So, you can drag around the parts on the left side bar to change that, and so if you drag a piece to the 7th spot on the side bar, you can see the first six pieces on the screen. Also, if you do make a mistake in ordering like this, you should delete all the constraints before trying to fix it.
- I should probably figure out how to do treads.
Next, Justin or Abhishek will need to put the electronic components on, and attach the harvester. Everything else is done.
CAD Offseason 2016