2axis
A robot that can move in the x and y axis. It is meant to be able to move an air hockey puck and play with you, but has the option to add any other attachment to it (like a pen for drawing or a laser)
Total Time: 5.5 hours
Day 1: July 1
Today I started by researching how to make a 2 axis robot. I looked into how 3D printers work, and realized a linear steel rod with a linear ball bearing works best and is the cheapest. With this, I started to make an onshape model. One problem I had was how to use special elements, like aluminum t-slots or ball bearings in my CAD. After doing some research, I learned I could link these models into my CAD, making it much easier to use special parts in my 3D model. I imported the bearing and aluminum tubes and then measured my air hockey table to find I need a frame 40 in by 36 in. However, I could not find an aluminum t-slot that long, so I traced the face sketch and extruded it to extend it. I edited the imported part to fit my requirments. I also made 3D printable brackets to attach to the aluminum tubes and hold the bearings. I was able to make the basic movement frame, and added mates and limits to simulate how it would move. I also added the grove to the main slider in order to be able to add multiple attachments to the frame. One problem I faced was that the horizontal length was slightly less than 36 in (35.66in), and it would be easier if the horizontal and vertical bars were the same. I spend some time changing dimensions to make room for the extra 0.44 inches. I also used a variable for the bolt, rod, and bearing diameter in case I can't find the exact dimensions I modelled. Overall, I was able to make the base to see how the robot would move (without any motors), and added variables to make easy changes later.
Note: I could not find the original creator of the aluminum tube and bearing, but the STEP files are in the onshape project (unsure if I used someone else's CAD or a linked CAD, since could not find name of owner or original document) (Not trying to steal credit or work, just no citations given by onshape about the model I imported)
Time spent: 3.5 hours
Day 2: June 2
Today was a parts research day. I spend the most of this session finding the exact parts I needfor the project so I can finish the CAD based on those dimensions. One problem was that the linear rods were very expensive, so I decided to use thinner rods (around 10 mm instead of 16mm). I was also able to find which stepper motor I am using and the driver, so now I will be able to make a case for the motor. I decided to use an arduino mega for the microcontroller due to it being cheaper, easier to use, while still having a large number of inputs and outputs. I also did some research and found that 1/4-20 nuts and bolts are best for t-slots. I decided to use 1/2 inch bolts and added it to the BOM. I also made the initial BOM and added all the parts and prices. Another thing I did today was make the attachments that go on the slider to see how the groove would work. I made two attachments (one from an air hockey stricker, the other for a pen), and added mates to see the sliding motion. Overall, today, I was able to find the parts I needed to continue the CAD and made a simple part to test the groove mechanism on the slider.
Time spent: 2 hours