Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Alternate use- mini golf challenge obstacle
08-28-2017, 03:24 AM (This post was last modified: 08-28-2017 03:52 AM by Jetguy.)
Post: #1
Alternate use- mini golf challenge obstacle
So I previously built the older PS3 based air hockey version and have a side project of building basically the same setup but to block or make it really difficult for putting through the obstacle. The frame is built from a combination of some normal 20x20 extrusion and for the linear rails section specific Open Builds V-slot style extrusion for the Delrin V-wheels to roll on.

I'm using it with a mini ITX board with an i7 4790 and the PS3 cam running Windows 7. Also using the standard jjRobots electronic brain shield (robbed from my iBoardbot until the second brain shield just came in the mail yesterday.

So the good- it works and fully understand the basic parameters of setup and have it tracking golf balls and it works well. I set up an end "goal" and side rails (shown in the pictures tonight in aluminum but are actually 1x1 inch wood being painted black at this exact second. Again, I modeled this after the standard basic dimensions and out of the box it didn't take much to get it all running.

That said, this is where I need help for this adaptation.
I want to move the resting or parking position away from centered across the goal position in the middle. I want to park the machine "puck" left or right of the goal position waiting until it tracks the incoming ball to intercept. Again, I want to change the basic action that rather than parking in front of the goal centered I want to adjust it left or right (doesn't matter and can be either side) but as soon as a ball begins being tracked move to intercept in attack mode.

I think part of where to edit this is in the robot file of the Arduino code and potentially line 97? com_pos_x = ROBOT_CENTER_X; //center X axis
What I am concerned with is breaking the code. I'm not a programming expert and just enough to be dangerous to myself. I'm just worried that if I use a fixed X value does that break the code elswhere and cause bad things.

I posted the pictures here for now and will update with a full BOM and details as this progresses. Any help that you can provide as a pointer to editing the source code as I think even for air hockey being a little sneaky and parking just to the side of the goal (even trickier if random one side or the other) in the resting position.

Also, I actually have a lot more mods under the hood of this to make it perform even stronger for this task. The first being I cut the pins on the A4988 stepper drivers for the Vmotor pin so that rather than the standard 12V, I'm pushing the drivers only to 24V for absolute maximum stepper performance. I have an extremely powerful fan and special thermal epoxied heatsinks to the genuine Pololu brand A4988 stepper drivers (they claim better thermal performance than your typical cheap red A4988s from the typical sources). Also using some large NEMA17s with relatively low inductance values for maximum speed, but retained the printed plastic 32t pulleys to keep the steps per mm identical to stock.
I'm sure my moving mass is slightly higher than the 3D printed parts but considering the golf ball I'm trying to hit is also heavier than a puck the masses kind of work out.

Again, it would really help me out if anyone who better understands the source can give me a few pointers of what is safe to edit or even add this feature request to be able to adjust the parking/resting position off just to the side of the goal rather than parking centered.

Also, just a note about frame details. Sorry for the late night and relatively dark pictures. I'll take day shots tomorrow and some action video shots. I covered the frame rails by hot gluing black EVA foam strips to prevent reflections as they were interfering with the camera tracking. This has proven to be extremely effective and solved a bunch of problems specific I had to tracking.
What is also not shown is that I have a thicker foam covered adjustable paddle that bolts to the blocking arm hanging down and can be adjusted to match the surface (turf carpet). This both dampens the blow of striking the golf ball and reduces the forces on the components.

Another key factor of the frame is that the side rails and goal are adjustable to be spaced in from the side uprights so that I can fine tune the rail to match the physical XY the blocker can hit. Again, the actual rails are a 1x1 pine set of boards being painted black tonight and then the far end has a roughly 6 inch "goal" gap between the end wood rails to copy the basic dimensions of the standard air hockey table used in the actual EVO Air Hockey setup. Also, I am considering placing a board or aluminum panel raised at the far goal end under the carpet to give the same roll back effect of the feet mod mentioned in the Evo instructions. This will only be a slight rise and again I can set this frame on top so that the entire system maintains a uniform gap between the pusher blocker and the turf surface.

What is also not shown well is the upper panels you may see in the photos will be a scrolling LED sign to give it a little flash. This is a Raspberry Pi3 and the Adafruit RGB matrix hat and 2 each 32x64 panels in series https://learn.adafruit.com/adafruit-rgb-...i/overview I'm debating if to have this tied to a way to detect a "goal" scored when the user makes it past the
Find all posts by this user
Quote this message in a reply
08-29-2017, 05:04 AM
Post: #2
RE: Alternate use- mini golf challenge obstacle
Here is a video in action https://youtu.be/wV-o3IFHSss
Sorry in advance, this was shot with one hand trying to hold the camera and operate with the other.
Find all posts by this user
Quote this message in a reply
08-30-2017, 10:22 AM
Post: #3
RE: Alternate use- mini golf challenge obstacle
Wow! Very impressive structure. Smooth and sturdy. Great job Vernon! Do you mind if we post about your creation in the webpage?
Visit this user's website Find all posts by this user
Quote this message in a reply
Post Reply 


Forum Jump:


User(s) browsing this thread: 1 Guest(s)