Force Sensor
Go to Home Page

Out of Stock    Force       $24.00                 

Using this sensor with NXT requires a Lego NXT conversion cable (W770323).

Measure how hard you are pushing or squeezing.

A force sensor lets your Lego Mindstorms RCX measure how hard something is pushing or squeezing. You can build a scale to see how much things weigh, or see how hard your robot can push or pull. The Force Sensor measures force applied to the blue button in the middle of the sensor top. It measures force between one to 15 Newtons . A mass of 1 Kg (2.2 pounds) has a weight (force due to gravity) of 10 Newtons.

This sensor is not very accurate or repeatable. It is not intended for laboratory measurement. It is intended to provide a rough indication of force in a working robot. The sensor is NOT capable of measuring force between zero and one Newton. The sensor is best programmed as an unpowered sensor in RAW mode. Maximum force is limited to4 Newtons when programmed as a light sensor in the standard RCX icon language.

Relay brick for Mindstorms

Force Sensor for Lego Mindstorms.

Programming

The Force Sensor is an unpowered sensor. It may be programmed as either a powered or an unpowered sensor. If you are using Robolab, use the generic unpowered sensor icons. If you are using NQC or similar text languages, program the sensor as a passive (unpowered) sensor in the RAW mode. If you are using the standard Lego icon language, you can program it as a light sensor. When programmed as a light sensor, the measurable range is about 1 to 4 Newtons . If you are using NXT G-code, program it as a temperature sensor and use the RAW output as shown below.

Using the G-code temperature sensor icon to read an unpowered sensor in raw mode.

Typical RCX values for unpowered RAW mode.

Typical RCX values when read as a light sensor.


Time delay

It takes some time for the foam rubber to be squeezed down after a force is applied. The graphs below show how the RCX value varies over time, for two different amounts of force. The graphs were created with Robolab Investigator using the generic unpowered sensor icon.

                           2 Newtons                                                                        5 Newtons

   


Example: Scale

The scale below provides a stable mechanical platform on top of the force sensor.

Connector for Mindstorms relay control

Simple Scale using Force sensor.

Short shaft (black) pushes blue button on sensor.


Specifications

•  Brick Size: 2 bumps by 2 bumps.  Height is one and one thirds bricks.  (one brick plus one flat plate). Overall size: 16 x 16 x 15 mm. (.625 x 0.625 x .575 inch)

•  Mindstorms black electric connector on 6 inch (10 cm) cable.

•  4 mm (.15 inch) blue button actuator

•  Passive (unpowered) sensor.

•  Resistance 500K with no force, 500 ohms at 15 Newtons..

Technical Description

The force sensor contains a piece of foam rubber that has carbon dust mixed in the rubber. Carbon lets the rubber conduct electricity.. Electricity flowing through the foam must follow a long path, going around all the air pockets. As you push on the blue button, the foam rubber gets squeezed together. The air gets squeezed out, and electricity has a shorter path. A shorter path means lower electrical resistance. Your RCX measures the electrical resistance.

 

jordan 11 legend blue legend blue 11s jordan 11 legend blue black infrared 13s jordan 11 legend blue black infrared 13s jordan 11 legend blue jordan 11 legend blue jordan 13 black infrared jordan 11 legend blue jordan 11 legend blue legend blue 11s jordan 11 legend blue jordan 11 legend blue jordan 13 black infrared 23 jordan 13 black infrared jordan 11 legend blue legend blue 11s jordan 13 black infrared jordan 11 legend blue black infrared 23 13s legend blue 11s black infrared 13s jordan 11 legend blue jordan 13 black infrared 23 jordan 13 black infrared 23 jordan 13 black infrared jordan 13 black infrared 23 jordan 11 legend blue legend blue 11s black red 13s legend blue 11s jordan 11 legend blue black infrared 23 13s legend blue 11s jordan 11 legend blue jordan 11 legend blue legend blue 11s jordan 13 black infrared legend blue 11s michael kors Black Friday michael kors black friday michael kors Black Friday coach black friday michael kors black friday michael kors black friday kate spade cyber monday moncler black friday hollister black friday lululemon cyber monday canada goose cyber Monday burberry black friday victoria secret black friday under armour black friday Tiffany cyber monday Oakley cyber monday kate spade cyber monday victoria secret black friday jordan cyber monday michael kors cyber monday jordan cyber monday north face black friday victoria secret cyber monday nike cyber monday uggs cyber monday north face cyber Monday michael kors black Friday beats by dre black Friday canada goose black friday michael kors black Friday north face black Friday beats by dre cyber Monday lululemon black Friday beats by dre black Friday moncler cyber monday north face cyber Monday canada goose black friday lululemon cyber monday beats by dre black Friday uggs black friday north face cyber monday deals uggs cyber monday michael kors black Friday michael kors black Friday nike cyber monday beats by dre black Friday Versace black Friday the north face black friday michael kors cyber Monday michael kors black Friday uggs cyber monday Babyliss cyber Monday black Friday beats by dre michael kors black Friday michael kors black Friday beats by dre cyber Monday lululemon black friday Babyliss black Friday louis vuitton black Friday coach black friday coach cyber monday michael kors black Friday north face cyber monday kate spade cyber monday lululemon black friday bose black friday Babyliss cyber Monday uggs cyber monday michael kors cyber Monday north face cyber monday uggs cyber monday Juicy Couture cyber monday uggs cyber monday beats by dre cyber Monday Tiffany cyber Monday moncler cyber monday uggs cyber monday beats by dre black Friday sale beats by dre black Friday north face cyber monday gucci cyber monday lululemon black friday michael kors black Friday beats by dre cyber Monday uggs black friday lululemon cyber monday uggs cyber monday michael kors black Friday uggs black friday uggs black friday uggs black friday uggs black friday uggs black friday uggs cyber monday uggs cyber monday uggs black friday north face black friday beats by dre cyber Monday beats by dre cyber Monday beats by dre black Friday beats by dre cyber Monday beats by dre black friday beats by dre cyber Monday north face cyber monday beats by dre cyber Monday north face black friday michael kors cyber monday michael kors cyber monday michael kors cyber monday michael kors cyber monday michael kors cyber monday michael kors cyber monday michael kors black friday michael kors cyber monday michael kors cyber monday uggs cyber monday uggs black friday north face black friday uggs black friday uggs cyber monday uggs black friday uggs cyber monday uggs cyber monday north face black friday uggs black friday north face cyber monday