Building the Doomsday Machine from "The Pink Panther Strikes Again" - Part I: Wooden Structures

Next month, our local Community Theater will be performing "The Pink Panther Strikes Again". In case you don't remember (... I never remember which title matches which plot in the Pink Panther series), this is the one in which Dreyfus threatens to destroy the world with the Doomsday Machine shown in the picture.

A group of  artists has already painted beautiful set pieces, and I volunteered to build the Doomsday Machine. Based on my experience from building movie props, like the Flux Capacitor, or the HAL 9000 computer, I think I will be able to build an Arduino- and Raspberry Pi-based prop that will exceed the expectations. The play is in four weeks, so I have about two weeks to finish this.

Plans

Everything starts with a plan. In discussions with the director, we decided that the Doomsday Machine should have a height of about 6 feet. For the theater play, given the time and budget constraints, it is not possible to build a decent replica of the machine from the movie. On the other hand this is also not required. From my point of view, it just has to be impressive in size (a sized of six ft should do that) and in terms of the light effects. If there are enough lights, then programming the different patterns should take care of that. While the machine is supposed to make hums and other sounds, this be be done by the theater sound person - so the machine itself does not need any audio capabilities.

My initial sketch shows a design that is roughly based on the shape as seen in the movie. It is made of three parts: The bottom ("base") has an octagonal structure (everything SciFi is octagonal, right?), the center piece is a rather simple box, and the top piece ("laser gun") is a cylinder with some add-ons. The center piece holds a computer monitor plus switches and LEDs (controlled by an Arduino). The laser gun has a few (maybe 5-8) vertical LED strips. When these are illuminated in steps, from left to right, it gives the feeling that the laser is being fired. I still have a computer monitor lying around that I bought for 4 bucks at a Thrift Store. This is connected to a Raspberry Pi, and simply showing some images that one would expect to see on a computer screen in a SciFi movie. The LEDs on the center piece will blink in various patterns, indicating (a la Star Trek) that the computer is operating.

Main Structure for the Base

[Sun, Sept. 15]  A little geometry helps to figure out the relation of eight side pieces and the width of the octagons for the base.

A little more geometry is needed to determine (for a given height) the length and the angle of the connections between the lower and upper platforms of the base. For a total height of 26", the side pieces should be 26 1/4" long, and cut at an angle of 8.5 degrees.

And these are all pieces that need to be cut for the base.

From Lowe's, I got a few pine boards 3/4" x 12", 4 ft long, and a large 4ft x 8ft sheet of 3/16" plywood. The pine boards are cut into strips of 3/4" x 1 1/2",

and (at 22.5 deg angles) into the appropriate lengths (13" and 10") for the lower and upper levels of the base.

The plywood is cut into octagonal shape,

 and the wooden strips are glued and screwed onto the plywood.

 Finally, the vertical bars (cut at 8.5 deg angle) are glued and screwed to connect the bottom and upper levels.

This is the result: it is 26" tall, 31" wide at the bottom and 24" wide at the top. It is stable enough to hold the expected weight. The open areas will later be covered with corrugated cardboard (I get this from Sam's Club). It only needs to look good from a distance, and the cardboard keeps the weight small. The cardboard will be painted and decorated with various items.

Main Structure for the Center Piece

[Tue, Sept 17] The center piece is a simple box that will hold all of the input/output elements. The basic structure is a frame.

This center piece is 25" tall, 21" wide and 12" deep.

The sides will be made of plywood pieces that are glued/screwed to this frame. The front side has all the openings for the computer monitor, the LED lights, the switches, and a joystick. These are made using a laser cutter.

Main Structure for the Laser Gun

 [Wed, Sept 18] Like the original prop, doomsday machine will feature a laser gun at the top. The laser gun is a cylindrical piece, with a cone at the front, and a stick pointing outwards. The cylindrical structure is based on six wheels with inner holes that will hold the stick. These wheels are cut with a laser cutter. Two of the six wheels have additional areas that are later used for mounting the laser gun on the center piece.

The wheels are connected by eight wooden bars with notches (cut on the table saw) to glue them onto the wheels.

This design was a spontaneous idea and, initially, I was skeptical if it might be hard gluing the pieces together. But it turned out to be very simple, and it came out fairly accurate.

I love how this looks like! Later, the wooden (3/8") stick will be glued to the two wheels in the front, and the whole structure will be surrounded with cardboard, glued to the wooden bars.

continue with Part II: Finishing the Enclosure and Part III: Electronics, Arduino, Raspberry Pi