The Waiting Hand


The Waiting Hand is a kinetic sculpture comprised of a mechanical hand that repeatedly taps its fingers in wait. It is a visual metaphor of life and death, reduced down to one singular action. The hand exhibits delicate life-like movements, taking on a personality in itself, and makes it easy to identify with on a personal level as it is a symbol for how we touch, feel and experience life. The hand’s entire existence consists of one action: the tapping of its fingers, which it carries out in a repetitious, mechanical manner as it waits for something to happen. The only real change or event that occurs is that the hand ceases its movement completely when someone approaches it – a representation of death.

The same dynamic is paralleled in the experience of the viewer, who is inclined to approach the intricate moving sculpture in order to get a better look. They approach the piece intending to improve their experience of it, anticipating certain expectations. When they approach the hand however, they are only greeted by its stillness. They don’t get a chance to experience anything and now the wait is transferred onto them. They soon realize that their experience is over before it began.

The interactivity is integral to the concept of the piece as half of its purpose is realized only when someone approaches it. There is no overt statement or singular purpose in the piece, as it is intended to leave the viewer with more questions than answers. They are meant to think about its meaning and the outcome of their experience. By pondering the purpose of the hand and its motion, the feelings are transferred onto pondering the meaning of life and death. What is the purpose of our actions? Do we wait too much? What are we waiting for? The answers will be unique to every individual.


The Waiting Hand is a kinetic sculpture that is made up of a mechanical hand driven by various axels, wheels and pegs, which allow the fingers of the hand to move in a tapping motion. This motion is repeated in a loop and powered by one main axel which is controlled by a parallax continuous rotation servo. An IR sensor placed in the front of the piece measures the proximity of the user and controls the hand’s execution of the designated behaviours. The minimalism of the aesthetics of the piece is reflected on the detailed, realistic representation of a life-sized human hand which is white, while every other component of its surroundings is painted black. The contrast also acts as a spotlight, focusing the eye on the hand and its delicate movements.

Measurements: width 15.5” / height 9” / depth 11.5”

Progress Pictures

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Project Plan

Title: The Waiting hand
Concept: Life and Death reduced to one minimal action
Execution: Kinetic sculpture – a hand repeatedly tapping its fingers

1) Make the hand
Mix and create a mould and pour the cast into it
Materials: Alja-Safe Alginate, Smooth-Cast 300

2) Cut & shape pieces of hand
Saw the hand into the appropriate pieces to allow movement and proper alignment
Components: Four fingers, Thumb, Palm
Hand saw, Jigsaw, Dremmel

3) Create axel for finger pivots
Drill holes across knuckles for the wire to pass through
Drill, drill bits
Materials: Wire

4) Line up fingers & movement
Line up the fingers and wire and drill holes below them for the rods to poke through
Tools: Drill, Hammer
Materials: Wooden base, marker, ruler

5) Line up mechanism
Find the median line of all four points where the axel will be positioned. Line up the axel for the wheels so it sits directly below the rods. Attach the axel to the servo motor and adjust the height of the motor so the axel rotates on the spot.
Materials: lower wooden base, wooden dowels, balsa wood, servo

6) Make wheels
Create the wheels and line them up below the feet of the rods. Glue smooth plastic strips to outside of wheels and to the bottom of the feet to  minimize friction. Rotate them to the appropriate starting position and fasten them in place.
Materials: balsa wood, thin plastic strips, hot glue

7) Attach everything in place
Spray paint the wooden structure and wooden rods. Attach electronics to base and sensor to front of the box, attach thumb and palm in place.

eXploration IV – Making the Hand

I thought the easiest way to go about this was to cast a real hand, so I went about getting some materials. Making a reproduction of a hand requires making a mold, into which the hand is then cast.

My first attempt was a lazy one, as I decided to get my materials from the conveniently located Curry’s Art Supplies. The materials were Alginate for the mold (also used by your dentist for teeth impressions), and for the cast something called Clear Casting Epoxy. The alginate hardened extremely quickly, faster than i could mix in the water, but the mold came out ok. The cast instructed to leave it for 72 hours, thats three days! I got impatient and took it out after 24 hours, only to find some air-bubble-filled reproductions of fingers.

The mold

The cast

I then decided to go for the real thing, which meant going to Sculpture Supply Canada. I didn’t have time to wait for a shipment so I decided to go to there in person. It is a bit of a journey to get there, but it was worth it for the results. They have materials designed specifically for body casting: Alja-Safe Alginate (not mint flavoured like my previous purchase), and Smooth-Cast 300, a fast curing liquid plastic. The result was an awesome reproduction with incredible detail and realism.

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eXploration III – Mechanics sketches

The motion will be on the four fingers of the hand, which will move consecutively with a bit of overlap. I know that I want the motion to be revolving around one axel, allowing the use of just one servo motor.

Idea #1:
Four rods that go through the fingers will be rotating around one axel. Fixed to another axel will be circular shapes with a protruding bump that are positioned to hit the rods at certain times.

Idea #2:
The four fingers will have one rod going through the knuckles. The motor and mechanism will be placed below the hand and used to push up rods that will nudge the fingers up. The mechanism will be made up of one axle, on which circles will be rotating. The circular pieces will be rotating off centre in order to bump the rods at different heights.

eXploration II – Continuous Rotation Servo

To make the hand, I need to use a servo that is able to rotate 360°, so I’m using a parallax continuous rotation servo. After some quick reading I realized this has to be coded differently than the standard servo that I’m used to, with a few added lines of code. The servo can be made to move clockwise, counterclockwise, or be made to stop based on the right combination of values. A certain value can make it go one way, and a different value the other way, and as you move slowly from one value toward the other, the servo runs slower, then stops, then slowly gains speed in the other direction.

I need to make the servo respond to a distance sensor, where it will rotate continuously unless someone is in close range to the sensor. I found this helpful code here. I played around with the numbers and had to tweak the values slightly to make the servo come to a full stop. The first for loop makes it stop, the second makes it rotate right:

int servoPin = 7;
void setup(){

void loop(){
int i;
for (i = 0; i <= 200; i++){
delayMicroseconds(1498); // 1.5ms
delay(20); // 20ms}

for (i = 0; i <= 200; i++){
delayMicroseconds(1200); // 1.2ms
delay(50); // 20ms}

I took this code and added a sensor that would make the servo rotate unless someone was standing in front of the sensor, which is when it would come to a full stop:

#include <Servo.h>
int servoPin = 7;

void setup() {
Serial.begin (9600); // (speed) sensor

void loop() {
int distance = analogRead(0);

if (distance > 400) {
stopTap();  }
else {
tap();   }

void stopTap() {

void tap() {