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Lucinda Childs : Vehicle
Performance Engineer : Peter Hirsch

October 16 & 23, 1966

Cast: William Davis, Alex Hay. Slides: Les Levine

Lucinda Childs performing in 'Vehicle'. Photo: Adelaide de Menil

Lucinda Childs performing during Nine Evenings. Photo: Adelaide de Menil

Artist Statement: Vehicle consists of materials animate, inanimate, air-supported (in one instance), which can exist in a non-static state and be observed in increased dimension as they come in contact with light and sound sources made available consistently or intermittedly by radio signals through-out the dance.

The Doppler sonar has ultrasonic beam sources and a receiver. The beam emits frequencies at a level which is greater than our hearing capacity. A moving figure or object passing in front of the beam interrupts it and sends frequencies back to the receiver of the sonar at a level determined by the velocity of the figure or object. What we hear is the proportional difference between the frequencies sent out and those returned through interruption of the beam,  and the resulting reduction in the frequency level is what makes the sonar audible. Middle C (as we know it in music) is supposed to occur at approximately three feet per second of movement. This device, however, picks up movement of any duration or speed at the exact time that it begins or ends.

The ground effect machine is made from a General Motors refrigerator part which is designed as a platform to raise the 440 lb. weight of a refrigerator a fraction of an inch off the ground by the intake of air from a vacuum cleaner, thus making it possible to move the 440 lbs. with ease. The engineer, Per Biorn, installed two vacuum cleaner motors onto this platform so that I am in effect on a cushion of air when I use it.

I intend to utilize these devices in a set of circumstances as instruments which may or may not be efficient to the notion of completing anything. I do not feel that dance should be limited to the display of physical exertion alone; anything that can exist in a non-static state for a certain duration of time is of interest to me. My ideas are generally derived from the laws which govern the materials themselves and I attempt to allow the qualities and limitations of materials to be exposed in different situations.

Lucinda Childs wanted to translate body motion into something that corresponded to the energy of moving, and an engineer Manfred Schroeder came up with the idea of making a Doppler sonar in sound. In other words, sound beams at some fairly high frequency hit a moving object, and the reflective signal is beat with the outgoing signal, and the beat is audible. Peter Hirsch then built an 70 Kc Doppler sonar system for sound.


Another technical system Lucinda Childs used in Vehicle was the Ground Effects Machine (GEM) designed and constructed by Per Biorn. The six-foot high Plexiglas cage was held off the ground by air from 4 Hoover vacuum cleaner motors; it supported a person  standing inside this box and it actually could float above the floor around the room. Childs remarked, “ the ground effects machine was designed to be a little bit like a wind surfer that you would be able to move into space, depending on how you're balanced on it. So I like very much the idea of this object in relationship to the sonar beam.” But they soon discovered that the person inside the GEM pleixglas struture, could not guide it; so it was guided around the floor by a person outside it.


At the beginning of the performance, a Plexiglas cube is suspended in front of a large screen to the left, a fan is blowing on it, and it is slowly turning. First one light source throws the shadow of the Plexiglas cube in motion onto the screen. Childs then added one more light to double that image, and a third to triple the image. She then moved the cube to hang in front of a third large screen to the far right, where  it continued to rotate. A  light inside it, continued to cast its shadow onto the large screen. Alex Hay, entered in the GEM,  guided by William Davis, and holding a red fireman’s bucket with a light inside it. Alex delivered the bucket to Childs who hung it from a scaffolding. He returned back stage two more times and delivered two more buckets to Childs. Hay and Davis then continued to guide the GEM slowly around the floor of the armory. As Childs noted: The buckets were brought in by the Ground Effects Machine; I decided to I use this machine like a butler because I wanted to introduce it in a sort of functional way not  just a decorative way and give it a purpose. We could keep the light source in these buckets on from when they were brought on stage until they were hung on the scaffold.  And then with the buckets suspended from a simple scaffolding, the audience could actually see that the manipulation of the buckets and my movement affected the sound.

As Childs swung the buckets, the audience could begin to hear the sound produced by Hirsch’s Doppler sonar. It consisted of five 70 kHz ultra-sonic transmitters which were mounted alongside with microphones in the 3-foot high stands surrounding the scaffolding area. The signal reflected from an object moving in the ultra-sonic beam will have a slightly higher or lower frequency than the original signal. The frequency-shifted, or Doppler shifted, signal is picked up by the microphone next to the ultra-sonic transmitters and mixed with the original 70 kHz signal. The resulting beat frequency falls in the audible range. Childs began to swing the buckets Hay had given her in the plane of the ultra-sonic beams. Her movements and those of the buckets were picked up and translated into sound over the twelve speakers around the Armory.

The sound generated by the moving buckets can best be described as a swishing noise like wind blowing through a forest. The beat frequencies from the sonar system were also processed to create video images projected on a large screen to the left of the main activity. The lights in the buckets and lights surrounding the scaffolding were triggered off and on by the sound of radio station WQXR, not heard by the audience. Childs continued to push the three buckets around in varying patterns and speeds.

Towards the end of the piece, a series of slides were projected on the screen through the swinging buckets, first of the shadow of a bucket, and then with the camera moved backwards, more and more stills revealed more swinging buckets, and finally the image of the three buckets swinging was projected on the actual swinging buckets. Then the lights went out.

Preparations & Technical Elements


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