The ultimate DVD tower is the Heroine 220. It stores 220 DVDs. A maximum of 10 towers were planned, providing a total capacity of 2200. In reality, skyrocketing rent and endlessly higher capacity disks make it unlikely that more than 4 towers will be built.

Each storage tower has 110 rows for DVD storage, packed as close together as the mechanical accuracy of the robot allows. Each row stores 2 disks.

To speed up accesses and resist collapse, the tower is divided into 3 modules of 37, 37, and 36 rows. Below each module is an express boundary which can be detected by the sled much more quickly than the rows. The sled quickly lowers to the nearest express boundary, then slowly ascends to the exact row. It also keeps the sides from bending under the weight of 220 disks.

The Heroine 220 towers weigh 25 lbs empty. They take up most of the room in the robot and are virtually indestructible. They take 1 month to build by hand.

With this kind of durability, a heroine 220 never forgets.

The towers were conceived in this original drawing. The interlocking mechanism was overkill but it looks cool.

Raw materials for a tower come in. They're made of highly fire resistant MDF and steel. We wanted to build out of plaster or fiberglass for ultimate fire protection but those were too expensive.

In one end goes 16 guage, plated steel wire and out the other end comes 220 steel row pieces.

Wood is marked with all the pieces.

Holes are drilled into the inside faces for the row pieces. After painting, they need to be drilled again from the outside to remove excess paint. Unfortunately drilling on the inside before painting is required to prevent the drill chuck from scratching paint. They have to be drilled from the inside to get the alignment right.

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Timelapse movie showing sanding of the wheel guides. The wheel guides are shaped with sand paper to achieve a 45° angle. This was the cheapest and most reliable wheel guide to make. Additional bevelling is done on the back of the tower even though the robot doesn't travel there because it looks cool.

Final sanding and alignment complete and ready to receive paint.

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3 coats of flat black paint are applied to the insides of the modules. The paint must withstand endless sliding of disks in and out.

The black backing prevents light behind the tower from interfering with the vertical sensor. Gluing the black backing is still a real pain because it must be pressed down manually until the glue dries.

Big, fat, expensive bolts hold the 3 modules together. They need a huge screwdriver.

Final assembly before aluminum painting. Except for the top extension, no glue is used. The screws are ground flat where disks are slid in.

3 coats of aluminum paint are applied. The wheel guide requires liberal painting to withstand hundreds of wheel movements.

While drying, the paint is brushed in vertical strokes to produce a distinct vertical lattice. Row pieces are painted white to increase reflectivity.

With the aluminum paint dry, the towers lay flat for further drying while the express boundaries are painted white.

The inverted gothic arches were another waste of time that looked neat.