This wind-driven version of Theo Jansen's Strandbeest is considerably simpler than most of the designs posted, using only 4 basic parts for the body of the beest. The first simplification is that the leg units print-in-place, pre-assembled. The second is that the crankshaft prints as a single, monolithic unit. Add 2 end pieces and connection rods on the side and you have yourself a Strandbeest!
This version is actually wind driven. In the animations shown, it is driven with a table fan on its LOW setting (I'm guessing maybe a 15mph breeze?). You have your option of chasing it around with a fan as it walks across your desk, or you can set it in the provided stand as a piece of kinetic art.
Printing
Printing is fairly straightforward. I recommend PLA for its stiffness and yield strength. The only areas that needs supports are the overhanging shafts on the crankshaft part. The other thing I changed from the standard settings is to slow down the print speed of the small perimeters so that the vertical shafts print with better layer adhesion.
For the basic beest, you will need to print two of the Legs plates (8 legs total) and one of the Misc plate. If you want to drive it around with a fan, you'll need to print the fan plate. The stand is optional, but nice for showing off.
Assembly
After printing the legs, all the pivots need to be broken free. Grasp adjoining links near the pivot point and gently crack each joint free. After everything is freed up, work each joint back & forth many times until it is completely loose. Wiht 8 legs, you can tolerate very little friction and still have it move under fan power. If a joint is particularly stubborn, you can work a razor blade into the horizontal gaps between the links. Lastly, apply a drop of light oil to each joint and wipe away the excess. | |
Each side rod has a long end and a short end. Starting with the long end of one rod, slide your first leg on in the orientation shown. (Note: in the subsequent photos, the gap in the C-shaped end of the lower connecting arm is different than in the files provided. The gap is in a different position. This has been tested, and it makes the arms easier to assemble.) | |
Stack all four legs onto the side rod as shown, with the feet at the bottom and the longer end of the rod to your right. Assemble both side rods in exactly the same way. | |
Place one of the end pieces on the table and press the long end of the left rod into the taller of the receptacles and press the short end of the right rod into the shorter receptacle. The rods should press firmly into place and end up flush with the table.
Note that the flat sides of the rods should be oriented towards the center of the frame. This isn't critical, it just looks better. | |
Place one end of the crankshaft into the center hole in the end piece. | |
Now the slide the other end piece over the other end of the crankshaft and press both sides onto the ends of the side rods. The ends of the side rods should be flush with the outer surfaces of the end pieces. | |
Now comes the tricky part. You'll be clipping the ends of the upper and lower connecting arms to each section of the crank shaft. Note that each axle section of the crankshaft has a flat section that is a little thinner. For each arm that you clip on, you'll need to rotate the crankshaft to an orientation where the gap in the C-section aligns with the thin section. You can then snap the clip over the axle.
But don't start yet! | |
The legs operate in pairs, with one right leg and one left leg driven from the same axle section. The connecting arms for the left and right legs need to be clipped onto the axle in a specific order, starting from back to front as shown in the diagram. | |
Let's get started: clip the upper arm of the left leg first. | |
Next clip the lower arm of the left leg. Remember, you'll need to rotate the crankshaft some to make the flat section align with the gap in the end of the arm. | |
Now do the lower arm of the right leg. | |
And finally, the upper arm of the right leg. | |
When finished, it should look like this.The crankshaft should turn freely and operate all of the legs as it turns. | |
Now press the 60 tooth gear onto one end of the crankshaft. Make sure it doesn't rub against the face of the end piece. | |
Insert the fan into the upper hole in the end piece so that the small gear engages the big gear. | |
Finally, insert the retaining clip into the groove in the end of the fan shaft to secure it in place. You are now ready to set up your desk fan to drive your Strandbeest! |