Welcome !

Presented By Vatsal ShahIU1241090055

INDUSUNIVERSITY

Presentation On : Flex Sensor

Electronics & Communication Dept.

5th Semester

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

A Flex and Force sensor. This is a flexible sensor which changes its output when it is bent or when force is applied on it.

This sensor has two output wires.

The resistance between these two wires varies when the sensor is bent or when subjected to a force. Hence, this sensor can be used as a flex or force sensor.

When the sensor is kept straight with no force acting on it, it has a resistance of around 10 K Ohms.

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When the sensor is bent in either way, or when force is applied on the sensor, the resistance between these two wires increases proportionally to the amount of bending.

They convert the change in bend to electrical resistance - the more the bend, the more the resistance value.

They are usually in the form of a thin strip from 1"-5" long that vary in resistance from approximately 10 to 50 kilohoms.

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

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Basic Circuit:

Flex Sensor as Voltage Divider - Output voltage increases with the bend. The impedance buffer in the circuit reduces error due to source impedance

of the flex sensor as voltage divider. Suggested op amps are the LM358 or LM324. We can also test our flex sensor using simple test, and skip op-amp.

Schematics

9 11 13 15 17 19 21 23 250.5

11.

52

Voltage vs Resistance

Resistance (Kohm)

Volt

age

(V)

R (Flex Sensor) Vout

9.48 kΩ 1.78 V

15.3 kΩ 1.69 V

17.0 kΩ 1.59 V

21.2 kΩ 1.36 V

22.7 kΩ 1.32 V

Flex Sensor – Test & DataVATSAL N SHAH

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

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Flex sensors are analog resistors. They work as variable analog voltage dividers. Inside the flex sensor are carbon resistive elements within a thin flexible substrate. When the substrate is bent the sensor produces a resistance output relative to the

bend radius. With a typical flex sensor, a flex of 0 degrees will give 10K resistance will a flex of 90

will give 30-40 K ohms. The Bend Sensor lists resistance of 30-250 K ohms..

How they Work

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

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Size: approx. 0.28" wide and 1"/3"/5" long

Resistance Range:1.5-40K Ω Temperature Range: -35 to +80°C Voltage: 5 to 12 V

Electrical Characteristics

Characteristics

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

Used copper tape to fix the problem Only one working flex sensor Reduced accuracy to differentiate between gestures Broke due to heat

Problems14VATSAL N SHAH

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

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1. Toys

3 . Fitness Products

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Application

What is Flex Sensor ?

How they Work?

Schematics

Characteristics

Project

Problems

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The parts required: Arduino UNO 10 x Red LEDs 9 x 330 Ohm resistors for the LEDs 1 x 10K Ohm resistors for the flex sensor. 1 x Flex sensor Wires and Breadboard to connect it all together

Project

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References:

http://forum.arduino.cc/index.php?PHPSESSID=los7pd7c6mjj40j78bcm5vudp6&topic=70883.msg527105#msg527105

http://sensorwiki.org/doku.php/sensors/flexion http://itp.nyu.edu/physcomp/sensors/Reports.Flex http://www.flexpoint.com/companyInfo/about.htm https://www.youtube.com/watch?v=ZJiwaAKHMNw https://www.sparkfun.com/products/10264 http://www.instructables.com/id/How-to-Make-Bi-Directional-Flex-Sensors/ http://www.imagesco.com/sensors/flex-sensor.html http://infusionsystems.com/catalog/product_info.php/products_id/54 http://www.digikey.com/us/en/ph/SpectraSymbol/flex_sensor.html http://www.adafruit.com/products/182 https://www.inventables.com/technologies/bend-sensor http://devices.sapp.org/component/flex/ http://www.nskelectronics.com/flex_sensor.html http://arduinobasics.blogspot.in/2011/05/arduino-uno-flex-sensor-and-leds.html

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Thank YouFor Your Attention !

VATSAL N SHAHINDUS UNIVERSITY