SHARP GP1S036HEZ: A PHOTOINTERRUPTOR TILT SENSOR

This is a subminiature sensor that measures tilt in one plane around a 360-degree range. However, it only has 2 bits (90) of resolution, indicating upright, upside down, on its left side or on its right side. The sensor has built-in photodetectors that measure the position of a ball within a chamber. The plane in which tilt is measured is defined by the gravity vector and by a line drawn through the center line of the device between the two rows of connector pins.

What is a photointerruptor? --- (derived from Sharp website)

A photointerrupter is a type of optoelectronic device that integrates a light emitting element (for converting electrical signals to light signals) and a light detecting element (for converting light signals to electrical signals) into a single assembly.

"'Two Types:"' transmissive photointerrupters and reflective photointerrupters.

Transmissive photointerrupters contain light emitting and detecting elements that are opposite each other, detecting objects that pass between them.

Reflective photointerrupters have a light blocking barrier that reflects light from the emitter and that gets detected by the detecting element.

The GP1S036HEZ is a transmissive-type photointerrupter.

APPLICATIONS

This sensor has been used in digital cameras and camcorders. I also found that a company called LABORIUS came up with a spherical robot called Roball and used this tilt sensor for position detection. http://www.usherbrooke.ca/uilo/offers/electronic/roball.htm

ELECTRICAL CHARACTERISTICS

GP1S036HEZ Datasheet: http://www.junun.org/MarkIII/Info.jsp?item=78

PhotoInterrupter Datasheet: http://document.sharpsma.com/Handler/getfile_handler2.asp?nodeid=Documents&fileid=7B98285C-809C-4B06-8D4A-A9162F408FCA

Looking at the above graph, I figured that the sensor is only able to take in a maximum of 1.4 V to operate. It may also produce a reverse voltage of 3V up to 6V max. The sensor's output seems to be a change in voltage coming from the emitter. I'm not sure of this. I know that the sensor is also described to involve a 2-phase output type. This sensor has two emitter leads and one collector lead. The collector operates with 5V and uses 55 to 300 mA.

PIN DESCRIPTIONS

This sensor has 5 leads. The sensor legs actually have a solderable part and a non-solderable part. Below is a diagram describing the representations of each pin.

MICROCONTROLLER CONNECTIONS

I am in need of guidance in this aspect. So far, I have this setup, following a transmissive-type photointerrupter schematic diagram I found at Sharp's website.

CODE SAMPLES

I tested the above setup with a simple serout of the ADCIN value from the 2 emitter leads of the sensor. I am not sure if this was the correct way of doing it. When I viewed the results through serial, I just got insignificant values from 1019 to 1023.

TYPICAL BEHAVIOR

Since I haven't gotten the sensor to work effectively at this time, I will be updating this section later. I need the class' input on my questions.

However, on my humble attempt, I was able to detect very minor voltage changes during tilt.

PositionEmitter 1Emitter 2
Upright4.864.86
tilt Right4.964.96
Upside Down4.864.96
tilt Left4.964.90

APPLICATIONS

I will be using this sensor on a previous project called the 'Cocktail Grooves.' This project requires a sensor to detect tilting of glass bottles / pouring liquid from a bottle to trigger other commands. This section will also be updated later.

QUESTIONS

1. Which is the output pin? The emitter or the collector? I think it is the emitter.

2. From the graph, I don't know what output changes to expect from the sensor. Does it produce voltage changes? most likely?

UPDATES: I FINALLY HOOKED IT UP CORRECTLY!

Here is the final Pin Diagram:

The following diagram shows a summary of results. Please note that this sensor is digital, or better yet, binary. It shows 'on-off' states in four different positions. Interestingly, instead of '1' for 'on,' the serial value showed '3.'