Nuts and Volts - September 2014

working on my first three-axis skull, I followed the conventional method and used several different software programs. These included VSA and products from Monkey Basic (see Resources), along with a joystick to set each individual movement for the nod, tilt, and rotate servos.

Through my work and while observing others setting up their routines, I found that most people didn’t really need that kind of control. What most of us were trying to achieve was just random movement since we really didn’t know where the guests would be in relation to our props. We just wanted our characters to appear lifelike.

I began trying to figure out how to program my PICAXE for random movement of the three servos and found that much of the work had already been done. Joseph Maddalena — also known as Hpropman on the Haunt Forum — had some code that would do just what I was looking for. He made the code available and I use it for the basis of the code I run many of my props on.

Building on the success of the EZ4, I soon decided I needed a board that would be versatile enough to control a variety of basic props. I wanted it to include a stereo sound card, be able to be triggered by a PIR (passive infrared) sensor, have a three-pin servo header, have a 12V/110V relay, and be able to run a 12V motor or light. You probably would never use all of these at the same time, but I wanted them available. This became my simple prop controller. It’s the board I reach for the most often when building a prop (Figure 7).

As I became more confident in my design skills, I decided to try my hand at building a button banger controller. The button banger style of controller does not require the end user to do any programming as it’s already on the chip. Once the PICAXE chip is programmed with the basic code, the actual routines are added by just pushing a few buttons in the desired sequence that triggers the appropriate relays which are connected to your prop motors, lights, or solenoids. There are several great controllers like this on the market, but I thought they could be made better.