New K'nex Ball Machine in Progress

I am about a week into the construction of my newest and most complex ball machine, which is currently unnamed. The machine centers around a massive two-axis overhead gantry which covers my entire room. When finished, the gantry will be able to automatically detect when a ball has been loaded into it, then deposit it in one of several tracks by the use of a random number generator. This video is the first test of bi-directional motor control in this machine. I will post a new video when I have a test of ball loading and depositing completed.

Continuously Variable Automatic Transmission - Finished

This is the finished model of my earlier Automatic CVT prototype. It contains 31 gears and roughly 2,500 pieces. The mechanical design has remained unchanged since the prototype, but numerous structural enhancements have been made to allow for operation at much higher speeds and torques. I plan to post a video of the transmission soon.

Continuously-Variable Automatic Transmission

This is phase two of my attempt to build a continuously-variable automatic transmission for use in gradually accelerating heavy objects to a very high speed without breaking motors and/or pieces. My first attempt was over a year ago (http://knexdesigns.blogspot.com/2010/10/knex-centrifuge-work-in-progress.html) which required an operator to manually adjust the torque output and had no variable gearing ratio. This new design, which uses two differential gear boxes, automatically switches the gear ratio between 1:1 and 1:6. Because the gear ratio is continuous, any ratio between 1:1 and 1:6 is possible, and acceleration between ratios is perfectly smooth. This prototype is fully functional, but still needs to be re-enforced and stabilized. I will post more as I continue work on it.

K'nex Projection Mapping Test

I have been experimenting with projection mapping lately, here's one set to music projected on Blue Fox.

K'nex Solar Death Ray

I think I can safely say that this is BY FAR the most powerful K'nex "gun" ever constructed, even if the main component is not technically a K'nex piece. Rather than blasting its target with a white rod shot shot from rubber bands, the "death ray" hits its target with 9.6 Kilowatts of solar energy, enough to reduce pennies to puddles in seconds.

My friend Paul and I bought a 4 foot by 3 foot Fresnel lens this morning. The obvious thing to do with it, of course, is turn it into giant solar magnifier, so we constructed a 1,500 piece K'nex frame for it. By the time we were finished it was 7 in the evening so the sun was fairly low in the sky, but it still got hot enough to vaporize pennies with ease.

I plan to post a video soon when we get a chance to try it mid-day.

Paul holding the death ray, attempting to melt a railroad spike.
The welding mask is necessary to look at the spot, it would blind you otherwise.

Close-up of the death ray vaporizing pennies.

Penny: before and after.

Small summer projects

Here's a couple of small projects I built over the summer.

Blue Fox - Final Video

Ten months of construction, four days of filming, two weeks of editing, here it is. The final video of Blue Fox, nearly a year in the making.

Blue Fox Video Progress

The final video for Blue Fox is, without a doubt, the most tedious video I have ever tried to make. My friend and I shot over 11 gigabytes of HD video the other night, and after trying 4 video editors (cyberlink, sony vegas, adobe premiere pro, final cut pro) and 2 computers, I still have been unable to find a video editor that won't either throw the audio out of synch or simply crash during the editing. From the looks of it, it'll be a while yet on the final video.

Wind-Powered K'nex Ball Machine

My friend Sam and I built this ball machine over the past few days using the pieces left over from Blue Fox. This is, to my knowledge, the first 100% wind powered K'nex ball machine ever constructed. The 6 foot tall lift hill is powered entirely by a 3.5 foot diameter wind turbine made only with K'nex pieces. It has over 4,000 pieces, stands 8 feet tall and has 50 feet of track. It is equipped with an automatic transmission which ensures that no matter what direction the blades turn, the lift hill always goes the same way, doubling its overall efficiency.
We call it Don Quixote.

Blue Fox - LED ball prototype

Using 3 button cell batteries and 2 ultra-bright blue LEDs, I created an illuminated K'nex ball, with light shining out both of the holes. The ball is extremely bright, and has a switch on the inside so it can be turned off. The two small blocks of foam keep the electronics centered in the ball so it does not get unbalanced and shield them from impacts.

Blue Fox - Video and possible logo design

Here is a possible logo for Blue Fox. The final version will be animated. I tried really hard to avoid using blue and orange contrast... but come on! Something is called the blue fox. That can't not be blue and orange. Just saying...

Also, here is 2 minutes of unedited, raw video of the finished machine as it will most likely be quite some time before I get an official video produced, I am still waiting on a friend of mine.

Blue Fox - Path Topology Diagram

This diagram shows the 17 connections between the 6 towers in Blue Fox. The towers are shown in their actual locations around my room. However, since this only shows path topology, the lines between them only show connections, not the actual shapes and routes of the paths. I used this diagram to help balance the number of incoming and outgoing paths from each tower as I constructed the machine.

Blue Fox - DONE!

My most complex ball machine to date is finally finished after 10 months of construction. It has 22,000 pieces, 120 moving parts, 86 gears, 16 paths, 7 motors and 6 lifts. I’ll make a video later, right now I have a lot of reliability testing to do.

Blue Fox - New Tracks (also 100th post)

This is my 100th post on this blog!

Also, here is an update on the construction of Blue Fox.
Since finishing the spring semester, I have had tons of free time to resume work, and construction is progressing rapidly. I have already constructed four new paths: The giant loop, the robot arm, a medium-length roller green roller coaster track, and a vertical drop track. At the moment I am working on general reliability as well as balancing the topology of the machine, in other words, making sure a ball lift doesn't have too many inlets or outlets, and that balls spend equal time in each segment. I plan to upload a topology map later, something which I have never done before. With a machine this complex, however, I feel that it is necessary.

I have also reprogrammed the robotic arm. It now operates at nearly twice the speed, as well as taking a new path which avoids the tracks I have placed in its way. I'm still a ways away from completion, however. Because this is the most complex K'nex machine I have ever constructed, reliability testing will take a very long time.

New Track - Giant Loop

I can not bring myself to construct a large ball machine without including the classic giant loop. Despite my success in constructing the first successful K'nex corkscrew, that track has been abandoned for reliability and space issues. This has freed up space to construct the two new tracks I have posted recently. Due to the space taken up by the loop, the programming for the robot arm track had to be adjusted, slipping the arm through a tiny gap in-between the loop supports and the giant supporting arch. With this track, I hope to add some balance to the flow of the balls from tower to tower.

K'nex Ball Machine Robot Arm Track Test 1

The robot arm is now fully integrated into the rest of the machine.

2-axis K'nex robot arm proof-of-concept

Bi-directional K'nex Motor Control with an Arduino

So this is what I'm up to this week, now that I am done with school. I purchased a bunch of new electronic components, as well as two new k'nex motors, and am experimenting with programmable bi-directional control. So far it's working great, I plan to integrate this into my latest ball machine, if possible.

Blue Fox - Interactive 360° Panorama

I discovered Photosynth recently, so I made a 360 degree panorama of my room/ball machine. This way, you can see the entire machine in a 105 megapixel image rather than one piece at a time, because it really is impossible to photograph it all at once.
Anyway, enjoy! Link

Blue Fox - Preview Video

This video is now two months old, but I just realized I completely forgot to post it here. You may have seen it on my youtube channel, but here it is.






There are 11 working paths in this video.

K'nex Corkscrew

Corkscrews are relatively common in K'nex roller coasters, so I decided to make one with a 2-railed ball track. After several days of tedious fine-tuning, I finally have a working model completed. I can not guarantee that this will make it into the final machine, as reliability may become an issue, but here it is now. Filmed at 30, 300 and 840 frames per second.