Strandbeest

Hi there, the Strandbeest is one of my semester projects and i would like to share it with you. The Strandbeest is a walking machine that moves by means of the coupling gear mechanism made famous by Theo Jansen.

The aim was to build a fast and lightweight running machine powered only by a 9V battery. 

It achieved a speed of 0.5m/s at a weight of 250g!

If you've got any questions or improvements to my design let me know!

Have fun building!

@ridgedworks

SEE VIDEO BELOW

A FDM printer is sufficient for the majority of parts.

I would recommend using the same geared motor, as it can lead to movement problems with other transmission ratios.

All moving parts must be easy to move, but must not have too much play. Have a drill and some sandpaper to hand just in case.

What else you need:

- Gear motor (3-6V, 1:90 gear ratio, metal gearbox, double axle, 200upm)

- 9 Volt battery

- Battery housing (preferably with switch)

- Alu/Carbon tube (6mm)

- Instant adhesive

- Cable ties

Frame

The frame consists of five parts. First, the motor mount must be glued to one of the two inner panels. Then the two inner panels are each glued to the outer frame parts. Make sure that they are aligned parallel. 

The motor and battery can then be placed in the brackets provided and the other half of the frame assembled. Cable ties can be used to hold the frame together during further assembly.

Drive Train

The drive train consists of the crankshaft and the crank, which are glued together. Caution! Both cranks must be glued to the crankshaft in the same orientation! For example, align the long side of the crank with the engine slot. 

This prevents the leg movement from being incorrectly timed.

Both crankshafts can then be inserted sideways and attached to the engine offset by 180 degrees.

Then insert the two aluminum/carbon tubes (16 and 20 cm) and slide on the spacers.

Switch on the engine and check whether the crankshaft rotates freely.

Preparation of the feet

A bolt must be glued to the back of each of the four triangular feet of the running machine. This is used to attach the C strut. Note that the bolts for one pair of legs must be glued on the opposite sides!

Leg pair

We start with the leg that is closer to the frame (no spacer on the tube). The struts J, F, C, K are placed on the bolts as specified in the last pictures and fixed in place with the end cap. To fix the leg 

Note that the pictures shows the left leg of each pair of legs. The image must be mirrored for the right-hand legs.

Now drill out the end cap for the pipe until it can be pushed onto the pipe with a little force. This fixes the leg to the pipe. Then slide two spacers onto the crank and start assembling the other leg.

Repeat this process for the other pair of legs.

Ensure that the leg pairs fit precisely at the connection points.