Accelerometer and Gyro Buying Guide - SparkFun Electronics

Accelerometerand Gyro BuyingGuideby Jimb0 | July 12,2010 | 10 comments Skill Level: Beginner

Accelerometers and gyros are becoming increasingly popular in consumer electronics, so maybe it's time youadded them to your project! Scrolling through SparkFun's sensors category reveals a huge list of these sensorsthat might be perfect for your next project, if only you knew what they did, and which one best fit yourproject. The goal of this buying guide is to get you speaking the same language as these sensor's datasheetsand to help you select the one that is best-suited for your needs.

What's an accelerometer measure? Well, acceleration. You know...how fast something is speeding up or

slowing down. You'll see acceleration displayed either in units of meters per second squared (m/s2), or

G-force (g), which is about 9.8m/s2 (the exact value depends on your elevation and the mass of the planetyou're on).

Accelerometers are used to sense both static (e.g. gravity) and dynamic (e.g. sudden starts/stops)acceleration. One of the more widely used applications for accelerometers is tilt-sensing. Because they areaffected by the acceleration of gravity, an accelerometer can tell you how it's oriented with respect to theEarth's surface. For example, Apple's iPhone has an accelerometer, which lets it know whether it's being heldin portrait or landscape mode. An accelerometer can also be used to sense motion. For instance, anaccelerometer in Nintendo's WiiMote can be used to sense emulated forehands and backhands of a tennisracket, or rolls of a bowling ball. Finally, an accelerometer can also be used to sense if a device is in a state offree fall. This feature is implemented in several hard drives: if a drop is sensed, the hard drive is quicklyswitched off to protect against data loss.

Now that you know what they do, let's consider what characteristics you should be looking for when selectingyour accelerometer:

Full-Scale Range – One of the characteristics that stand out the most is the accelerometer's full-scalerange – the upper and lower limits of what the accelerometer can measure. In most cases, a smallerfull-scale range means a more sensitive output; so you can get a more precise reading out of anaccelerometer with a low full-scale range.

You want to select a sensing range that will best fit your project, if your project will only be subjectedto accelerations between +2g and -2g, a ±250g-ranged accelerometer won't give you much, if any,precision.

We have a good assortment of accelerometers, with maximum ranges stretching from ±1g to ±250g.Most of our accelerometers are set to a hard maximum/minimum range, however some of the fancieraccelerometers feature selectable full-scale ranges.

Accelerometer and Gyro Buying Guide - SparkFun Electronics http://www.sparkfun.com/tutorials/167

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Interface – This is another one of the more important specifications. Accelerometers will have eitheran analog, pulse-width modulated (PWM), or digital interface.

Accelerometers with an analog output will produce a voltage that is directly proportional to thesensed acceleration. At 0g, the analog output will usually reside at about the middle of thesupplied voltage (e.g. 1.65V for a 3.3V sensor). Generally this interface is the easiest to workwith, as analog-to-digital converters (ADCs) are implemented in most microcontrollers.

Accelerometers with a PWM interface will produce a square wave with a fixed frequency, butthe duty cycle of the pulse will vary with the sensed acceleration. These are pretty rare; we'veonly got one in our catalog.

Digital accelerometers usually feature a serial interface – be it SPI or I²C. Depending on yourexperience, these may be the most difficult to get integrated with your microcontroller. That said,digital accelerometers are popular because they usually have more features, and are lesssusceptible to noise than their analog counterparts.

Number of axes measured – This one's very straightforward: out of the three axes possible (x, y, andz), how many can the accelerometer sense? 2- and 3-axis accelerometers are the most common thesedays. I'd suggest three-axis accelerometers; they're really no more expensive than one or two, andextra information can't hurt.

Bandwidth – An accelerometer's bandwidth represents how often the sensor can be read reliably.Bandwidth requirements will really depend on the application, but usually 50-100Hz will suffice.

Power Usage – If your project is battery powered, you might want to consider how much power theaccelerometer will consume. The required current consumption will usually be in the 100s of µA range.Some sensors also feature sleep functionality to conserve energy when the accelerometer isn't needed.

Bonus Features – Many more recently developed accelerometers may have a few nifty features,beyond just producing acceleration data. These newer accelerometers may include features likeselectable measurement ranges, sleep control, 0-g detection, and tap sensing.

Analog Devices' ADXL203CE and ADXL213AE - Older, power hungry, expensive, but very reliable,dual-axis accelerometers

ADXL203CE and ADXL213AE

AccelerometerFull-Scale

RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

ADXL203CE ±1.7g Analog 2 500Hz3-6V,

700-1100µASelf test

ADXL213AE ±1.2g PWM 2 500Hz3-6V,

700-1100µASelf test

Pros:


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Wide operating voltage range - can be used in both 3.3V and 5V systems.Less range means more resolution. If you need precise, low-g readings these are a good option.The ADXL213AE is the only accelerometer in our catalog with a PWM interface.

Cons:

Pricey - These are some of the most expensive accelerometers in the catalog. You can get comparable3-axis accelerometers for cheaper.Power hungry - you'll notice that ~1mA is quite a bit in comparison to the other sensors in thiscategory.

Analog Devices' ADXL320, ADXL321, and the ADXL322 - Our recommendations for those determined touse a 2-axis accelerometer


RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

ADXL320 ±5g Analog 2 500Hz2.4-6V,

350-480µASelf test


350-490µASelf test


340-450µASelf test

Pros:

Wide operating voltage range - these will work in both 3.3V and 5V systems.Low-current consumptionGood selection of ranges available. The ±18g range of the ADXL321 is actually relatively high, andwould be a good choice for projects with really fast starts and stops. For example, we strapped it to amodel rocket.Easy-to-use analog interface

Cons:

Only 2-axis - I'd recommend the comparable (not to mention cheaper) ADXL335 3-axis accelerometer,if the ±3g range works for your project.The ±18g of the ADXL321 means it has a relatively low resolution, only use it if you're going to takeadvantage of the full range.

Analog Devices' ADXL193 - That's a lot of g's!

ADXL193 Breakout Board


RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures


1.5-2mASelf test


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Pros:

Yeah...±250g. Even the above-mentioned model rocket was no match for the full-scale range of thissensor. Needless to say, if you have a project that requires an appearance by the ADXL193, you needto tell us about it!Wide operating voltage rangeBoth the chip itself and the breakout board are very small

Cons:

±250g means a very low resolution - the sensitivity of this accelerometer is 8mV/g, meaning a 10-bitADC (like Arduino's) will only be able to read data in steps of about 0.4g. This is definitely not theaccelerometer to pick if you need to sense gravity or other small accelerations.1-axis - If you're crazy project requires sensing huge accelerations in 2- or 3-axes, you may needmultiples of these.High current consumption, upwards of 1mA

Analog Devices' ADXL335 - Our 3-axis, analog accelerometer workhorse

ADXL335 Breakout Board


RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

ADXL335 ±3g Analog 31600 (x/y),550 (z) Hz

1.8-3.6V,350µA

Self test

Pros:

Very easy-to-use analog interface.3-axis accelerometer - the first one on this list!Low-cost - when compared to the 2-axis accelerometers above, it's hard not to go with this one.The ±3g range should provide a good balance of range and resolution.Low-current consumption - 0.35mA!We can't say enough good things about this accelerometer - we've put it into all sorts of other products

Cons:

The ±3g range can be limiting for some projects.Can only be supplied with up to 3.6V.

Freescale's MMA7260Q and the MMA7361 - Analog accelerometers, for those that can't make up theirminds on what range they need

MMA7260QMMA7361 Breakout Board


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RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

MMA7260Q±1.5, 2, 4,

6gAnalog 3

350 (x/y),150 (z) Hz

2.2-3.6V,500-800µA

G-select,sleep mode

MMA7361 ±1.5, 6g Analog 3400 (x/y),300 (z) Hz

2.2-3.6V,400-600µA

G-select,sleep mode,

0gdetection

Pros:

G-select! These sensors give you the flexibility to choose a measurement range that best suits yourproject. You can change the measuring range on-the-fly.The newer MMA7361 features a 0g detection interrupt. Perfect if you need to sense for free-fall.Easy analog interfaceVery low-priceThe sleep pin allows you to save power when you're not using the sensorThe MMA7260Q has been a SparkFun engineer favorite for a while, and is featured on quite a fewproducts (serial accelerometers, IMUs, UberBoards, etc.).

Cons:

The MMA7260Q has reached its end-of-life, and will be replaced by the comparable MMA7361.Unfortunately, the MMA7361 doesn't offer quite as much flexibility as it's predecessor, but it does have0-g detection.More complex (though, still quite easy) to get up and running - they'll require a few extra wires.

Analog Devices' ADXL345 and Bosch's BMA180 - Digital accelerometers with many great features

BMA180ADXL345


RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

ADXL345±2, 4, 8,

16gSPI and

I2C3 3200Hz

2.0-3.6V,40-145µA

Selectablemeasuring

range, free-falldetection,

tap/double-tapdetection,bandwidthselectable,

programmablepower modes

BMA180±1, 1.5, 2,

3, 4, 8,16g

SPI and

I2C3 2400 Hz

2-3.6V,650-975µA

Selectableranges,

programmabledigital filters,

interrupt


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features,programmablepower modes,

free-falldetection,

tap/double-tapdetection,

slopedetection

Pros:

A lot of flexibility in selecting your full-scale rangeBoth give you the option to choose which of the two serial interfaces you'd like to useDigital interface is less susceptible to noise than analogTiny...both physcially and power consumption-wise (40uA for the ADXL345!)So many features! The interrupts can be very handy depending on your project.Tap/double-tap detection means your accelerometer can work as a mouse buttonVery few external components necessary

Cons:

Digital interface may be more difficult to get up and running, but don't let that scare you off, we've gotplenty of examples.May require more wires than the ADXL335, at least if you're planning on using all of the features.Pricier than the 3-axis analog sensors, but still not too expensive

VTI's SCA3000 - The accelerometer of choice if accuracy is of utmost importance

SCA3000 Breakout Board


RangeInterface Axes

MaximumBandwidth

PowerRequirements

BonusFeatures

SCA3000 ±2g SPI 3 300Hz2.35-3.6V,300-650µA

Selectablefrequencyresponse,

temperatureoutput,

interruptfeatures

Pros:

This sensor offers the greatest accuracy of any of our accelerometers.Ambient temperature sensor is useful for further calibration of dataFree-fall and motion detection interrupts are comparable to the ADXL345 and BMA180The breakout board features a voltage regulator


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Cons:

Digital interface may require a bit more work to get it runningHigher price tag than other comparable sensorsOnly one range - may be limitingThe chip itself is rather large, but the breakout board's still pretty small

SparkFun's Choices

Easiest to use: ADXL335 - Nothing required beyond providing power and reading the output voltages.The full-scale range should work fine for most projects.Analog: MMA7260/MMA7361 - The ability to choose your sensing range and change it on-the-fly canbe a great luxury.Digital: BMA180 - A top-of-the-line sensor, hot out of the fab house. Lots of flexibility with 7selectable sensing ranges. The interrupt features can also come in very handy.

Gyroscopes measure angular velocity, how fast something is spinning about an axis. If you're trying tomonitor the orientation of an object in motion, an accelerometer may not give you enough information toknow exactly how it's oriented. Unlike accelerometers gyros are not affected by gravity, so they make agreat complement to each other. You'll usually see angular velocity represented in units of rotations perminute (RPM), or degrees per second (°/s). The three axes of rotation are either referenced as x, y, and z, orroll, pitch, and yaw.

In the past, gyros have been used for space navigation, missile control, under-water guidance, and flightguidance. Now they are starting to be used alongside accelerometers for applications like motion-capture andvehicle navigation.

A lot of what was considered when selecting an accelerometer still applies to selecting the perfect gyro:

Full-scale Range - Make sure the maximum angular velocity you're expecting to measure doesn'texceed the maximum range of the gyro. But also, in order to get the best possible sensitivity, make sureyour gyro's range isn't much greater than what you're expecting.

Interface - There's actually not much diversity in this section, 95% of the gyros we have feature an

analog output. There are a few that have a digital interface - either SPI or I2C.

Number of axes measured - Compared to accelerometers, gyros are a little behind the curve. Onlyrecently have inexpensive, 3-axis gyros begun to appear on the market. Most of our gyros are either 1-or 2-axis. When selecting those, you need to pay attention to which of the three axes the gyro willmeasure; for example, some two axis gyros will measure pitch and roll, while others measure pitch andyaw.

Bonus Features - Not much in this section is going to blow you away. Many gyros feature atemperature output, which is very useful when compensating for drift.


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Analog Devices' ADXRS610, ADXRS613, and ADXRS614 - Old, expensive, reliable, single-axis gyros

ADXRS61x Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features

ADXRS610 ±300°/s Analog 1 (z)4.75-5.25V,3.5-4.5mA

Analog temperatureoutput, self test





Pros:

Can be powered and interfaced at 5VEasy-to-use analog interfaceAnalog temperature output can be very helpful in stabilizing the readings

Cons:

Expensive - you can get similar 2-axis gyros for cheaper.BGA package is difficult to solder (if you're not using the breakout board)Relatively large and old - not that being old is a problem, but as time has passed gyro manufacturershave been able to pack much more into a smaller package

ST Microelectronics' LISY300AL and LY530AL - Our suggestion for those determined to use a single-axisgyro

LY530AL Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features

LISY300AL ±300°/s Analog 1 (z) 2.7-3.6V, 4.8mASelf test,

power-down

LY530AL±300°/s and/or

±1200°/sAnalog 1 (z) 2.7-3.6V, 4.8mA

1x and 4x outputs,self test, power-down

Pros:

Power-down feature is a nice way to conserve battery lifeThe LY530AL provides nice flexibility with two available measuring ranges±300°/s is a good balance of range and resolutionVery low-price - If all you need to measure is one axis, you can save money going with one of these.Relatively low current consumption


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These are both excellent single-axis gyros. We'd recommend the newer LY530AL due to the 4.5xoutput it offers. It also pairs really well with the LPR530AL 2-axis gyros a few sections below.

Cons:

Only 1-axis - there are 2-axis gyros available for not much more costThe LY530AL requires quite a few filtering components, if you're doing your own layout

Melexis' MLX90609-75, MLX90609-150, and MLX90609-300 - Flexible, single axis gyros with a fewbonus features

MLX90609 Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features

MLX90609-75 ±75°/sAnalogand SPI

1 (z)4.75-5.25V,16-20mA

Analogtemperature

output, self test


1 (z)4.75-5.25V,16-20mA

Analogtemperature

output, self test


1 (z)4.75-5.25V,16-20mA

Analogtemperature

output, self test

Pros:

If you can't decide whether you want an analog or digital interface, you don't have to!A lot of features you won't find on any other gyrosGood selection of rangesAnalog temperature output can be very helpful in correcting for drift

Cons:

Price is significantly higher than other single-axis gyrosRelatively high-current consumption

Larger footprint than most of our gyros (though the breakout board still comes in at less than 1in2)Limited to 5V power and interface

Invensense's IDG1215, IDG50, and the IXZ500 - Excellent all-around dual-axis gyros

IXZ500 Breakout BoardIDG1215 Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features


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IDG1215 ±67°/s Analog2

(x/y)2.7-3.3V,7-9.5mA

Temperature sensor,auto-zero

IDG500±110°/sand/or±500°/s

Analog2

(x/y)2.7-3.3V, 7mA

Temperature sensor,auto-zero, 1x and 4.5x

outputs

IXZ500±110°/sand/or±500°/s

Analog2

(x/z)2.7-3.3V, 7mA

Temperature sensor,auto-zero, 1x and 4.5x

outputs

Pros:

Breakout boards feature voltage regulationTemperature outputs help in stabilizing the angular velocity outputThe two available ranges of the IDG and IXZ500's provide a great mix of resolution and rangeWe've gotten a lot of mileage out of the IDG500, it's a great all-around sensor.Low-current consumption

Cons:

Quite a few external components are necessary to get them up and runningThe IDG1215 ±67°/s full-scale range means excellent resolution, but may not be enough of a range formany projectsSomewhat pricier than the ST dual-axis gyros

ST Microelectronics' LPR/LPY503AL, LPR/LPY530AL, LPR/LPY5150AL - Two axis sensors that getthe job done and offer a lot of variety

LYPR530AL Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features

LPR503AL±30°/s (4xoutput) or±120°/s

Analog2

(x/y)2.7-3.6V, 6.8mA

Self-test,power-down, 1xand 4x outputs

LPY503AL±30°/s (4xoutput) or±120°/s

Analog2

(x/z)2.7-3.6V, 6.8mA


LPR530AL±300°/s (4xoutput) or±1200°/s

Analog2

(x/y)2.7-3.6V, 6.8mA


LPY530AL±300°/s (4xoutput) or±1200°/s

Analog2

(x/z)2.7-3.6V, 6.8mA



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LPR5150AL±1500°/s (4x

output) or±6000°/s

Analog2

(x/y)2.7-3.6V, 6.8mA


LPY5150AL±1500°/s (4x

output) or±6000°/s

Analog2

(x/z)2.7-3.6V, 6.8mA


Pros:

This line of sensors features good mixture of range and axes combinations - you should easily be able tofind a sensor with the range and 2-axis-set that best fits your project.The LPR530AL is a great complement to the LY530AL for single plane, 3-axis angular velocitysensingPower-down feature is great for conserving battery lifeEasy analog interfaceVery low-cost

Cons:

As with a lot of these, all sensors require quite a few external filtering componentsThese gyros seem to be a bit more susceptible to drift than the comparable Invensense gyros in theprevious section

LPYR540AH - Finally a 3-axis, analog output gyroscope!

LPYR540AH Breakout Board

Gyro Full-Scale Range Interface AxesPower

RequirementsBonus Features

LPYR540AH±400°/s (4xoutput) or±1600°/s

Analog 3 2.7-3.6V, 10.8mASelf-test, 1x and

4x outputs

Pros:

3-axis! This is one of the first 3-axis analog gyros to hit the general market.Not too expensive - If you need three axes of angular velocity sensing, you'll save money using justone of these, rather than two different sensors.Very easy-to-use analog interface

Cons:

No power-down feature, like we're used to with other analog STMicro gyrosLow-availability at the momentCurrently only the ±400/1600°/s sensor is available. Not a lot of resolution if you're trying to sense very


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slow rotations.High current-consumption compared to the ITG-3200 below

Invensense's ITG-3200 - The mother of all gyros, 3-axis and loaded with features!

ITG-3200 Breakout Board

GyroFull-Scale

RangeInterface Axes

PowerRequirements

Bonus Features

ITG-3200 ±2000°/s I2C 32.1-3.6V,6.5mA

Programmable low pass filter,optional external clock input,

interrupt outputs,temperature sensor

Pros:

3-axis gyro! Triple-axis gyros are still pretty rare, so this one is very exciting.Comparably, very few external components requiredVery low current consumption, compared to the LPYR540AH aboveVery wide measuring range (±2000°/s), while still managing good resolution (16-bit ADCs on board)A lot of features no other gyros have availableTemperature sensor built-in, great for drift compensationSleep mode available, reducing current usage to 0.005mATiny!

Cons:

I2C may require more overhead to get up and running

SparkFun's Choices

Analog: Any of the analog ST gyros. Whether it's the three axis LPYR540AH or the single axisLY530AL, all of ST's gyros are very easy to work with, require very little power, and are dependable.The 1x/4x outputs offer great flexibility.Digital: The ITG-3200 is really top-of-the-line. If you need data from each axis of rotation and can dealwith the serial interface we'd definitely recommend this sensor.

Gyroscopes and accelerometers are great, but alone they don't give you quite enough information to be ableto comfortably calculate things like orientation, position, and velocity. To measure those and other variablesmany people combine the two sensors, to create an inertial measurement unit (IMU) which provides two to


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six degrees of freedom (DOF). IMUs are widely used in devices that require knowledge of their exactposition, for example robotic arms, guided missiles, and tools used in the study of body motion.

SparkFun's IMUs can really be broken down into two classes: simple IMU combo boards, which just mount anaccelerometer and gyro onto a single PCB, and more complex units that interface a microcontroller with thesensors to produce a serial output. If you've glanced over the previous sections, you should know what kindof specifications to be looking for in IMUs: the number of axes (both for the accelerometer and gyro), themeasuring range of the sensors, and the interface.

Analog Devices IMU Combo Boards - pricey, solid, 3DOF boards

IMU 3DOF Combo Board

Accelerometer/GyroAccel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range

Interface PowerBonus

FeaturesDOF

ADXL320/ADXRS6142

(x/y)±5g 1 (z) ±50°/s Analog 5V

Self Test,temperature

3

ADXL320/ADXRS6132

(x/y)±5g 1 (z) ±150°/s Analog 5V


3

ADXL320/ADXRS6102

(x/y)±5g 1 (z) ±300°/s Analog 5V


3

ADXL203/ADXRS6142

(x/y)±1.7g 1 (z) ±50°/s Analog 5V


3

ADXL203/ADXRS6132

(x/y)±1.7g 1 (z) ±150°/s Analog 5V


3

ADXL203/ADXRS6102

(x/y)±1.7g 1 (z) ±300°/s Analog 5V


3

Pros:

All of the Analog Devices' sensors are very solid and reliableThis is the only combo board you'll find with a 5V operating range.With all of the range combos, you should be able to find something that perfectly fits your project.

Cons:

Expensive, not a lot of bang for your buck - if you have your heart set on a combo board, I'd reallyrecommend the 5DOF IDG500/ADXL335 comboThe ADXL203 is relatively power-hungryAs the market has grown all of these sensors have gotten better and cheaper; who wants three degreesof freedom when you can get five or six for cheaper!

IMU 5 Degrees of Freedom IDG500/ADXL335 - A combination of two superstar, analog sensors

IDG500/ADXL335 5DOF


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IMU ComboBoard

Accel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


FeaturesDOF

IDG500/ADXL335 3 ±3g2

(x/y)

±500°/sand

±110°/sAnalog 3.3V


5

Pros:

This board combines two of our favorite sensorsAll outputs are analogAn analog temperature output is available from the IDG500 sensorTwo available gyro ranges provide good resolution and maximum rangeComparatively low-costSmall! This board packs a lot of inertia sensing into less than one square inch of space.

Cons:

Limited to just ±3g - this is a good balance of sensitivity and range for many projects, but may be toolow for othersNot a 6DOF!

ArduIMU Sensor Board - 6DOF (Main) - Just a 4DOF, but easily expandable to 5 or 6

IMU ComboBoard

Accel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


FeaturesDOF

ArduIMUSensor Board

- 6DOF(Main)

3 ±3g 1 (z) ±300°/s Analog 3.3VSelf test,

expandableto 6DOF

4

Pros:

Makes use of the ADXL335, one of our favorite accelerometersSimple, analog interfaceMates directly with the popular ArduPilot UAV Controller, providing it with information necessary toimplement an AHRS (attitude heading reference system) for unmanned aerial vehiclesA lot of support is provided on the DIY Drones Community websiteLow-price for a combo board

Cons:

The name of this guy is a little misleading -- this board alone provides a triple-axis accelerometer and asingle-axis gyro, so four degrees of freedom. However, combining it with a couple ArduIMU Daughterboards, provides the full 6-degrees of freedom.


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Designed mostly for use with the ArduPilot, but don't let that stop you if this IMU seems perfect foryour project

IMU 6DOF Razor - A super-tiny, inexpensive 6DOF

IMU 6DOF Razor

IMUComboBoard

Accel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


FeaturesDOF

IMU6DOFRazor

3 ±3g 3±300°/s

and±1200°/s

Analog 3.3VSelf-test,

power-down6

Pros:

It's a 6DOF!Packs a lot of punch into a tiny board. Not only is it less than one square inch, it's also much thinner(hence the 'Razor' nickname) than any of the other PCBs.Again makes use of the ADXL335 - noticing a pattern here? We really like that sensor!Combines the LPR530AL and the LY530AL to provide three axes of gyro sensingNine analog outputs in totalA common 3.3V source powers all three sensorsAll chips consume very low amounts of currentLow-cost - the cheapest 6DOF in our catalogPower-down control for both gyros, to save power when they're not in use

Cons:

Without multiplexing, many popular microcontrollers (Arduino, ATmega328/168) won't be able to readall 9 outputs.The board has no voltage regulators, you have to provide exactly 3.3V to the board.Limited to just the ±3g on the accelerometer outputsThe STMicro gyros are somewhat more susceptible to noise than Invensense's

6DOF v4 Sensor Board - The sensor guts of the beastly 6DOF v4, also includes three axes of magnetometeroutput

6DOF Sensor Board

IMUComboBoard

Accel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


FeaturesDOF

6DOFv4

SensorBoard

3±1.5g,2g, 4g,or 6g

3 ±500°/s Analog3.3V-16V

(3.3Vinterface)

3.3V regulator,Accelerometerg-select, 3-axismagnetometer

6 (+3magnetic)


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Pros:

It's actually a 9DOF! HMC105x magnetometers, and their supporting circuitry, are placed on theboard. The magnetometer can be used as a compass, providing the IMU's orientation with regard toEarth's magnetic field. This information is incredibly helpful if you need to know a device's exactposition.On-board voltage regulator output to all sensors - you can power the board at anywhere between3.3V and 16V.Built with sensors that we view as top-of-the-lineTwo IDG500s, mounted perpendicularly to each other offer three axes of gyro outputsAccess to the MMA7260Q's g-select pins, so you can choose the acceleration sensing range that bestfits your project

Cons:

Only the ±500°/s outputs of the IDG500s are broken outYeah...it's priceyIt is tailor made to be seated on the 6-DOF Controller Board, but that shouldn't stop you from using itfor your own pursuits, if it fits your project well.

IMUs with a Serial Output

All of the previous IMUs have all had an analog interface - one analog output per axis per sensor. This meansyou'll need 3-6 (or more) ADCs to be able to read all of the data. If you don't have enough ADC inputsavailable for all of that, you may want to consider one of these IMUs, which all interface a processor with thesensors, compiling all of the information into a single serial output. All of these IMUs come with firmware ofour own design, but you're free to customize the firmware as much as you'd like and program them yourself.

WiTilt v3.0 - A fully enclosed, LiPo battery powered, bluetooth enabled 4DOF

WiTilt

IMUAccel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range

Interface Power Bonus Features DOF

WiTiltv3.0

3±1.5g,2g, 4g,or 6g

1 ±150°/sBluetooth

(SPP)

LiPo,requires5V for

charging

Fully enclosed,LiPo charging

circuit, selectableacceleration range,report on thresholdoptionality, setableoutput frequency

4

Pros:

On-board processor is the popular ATmega328All components of the WiTilt are fully enclosed in a sexy, compact case. This means everything will


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stay in the correct place, and be safe from any tampering.Uses the MMA7260Q accelerometer, which features four selectable rangesThe included LiPo battery should be able to hold a charge for up to 12 hours of run-timeA wireless bluetooth output should work with any bluetooth-compatible computer or bluetooth devicethat supports Serial Port Profile (SPP)Our firmware is loaded with features - you can set the WiTilt to only report accelerations beyond aparticular threshold, set the output frequency, set the accelerometer range, and more!

Cons:

Does not include a 5V LiPo charger. The connector is a bit funky, you'll likely need to purchase abarrel-jack to 2-pin JST adapter.Somewhat high price tagOnly 4DOF - not really a huge negative, but there are a lot of 6DOF options hereMMA7260Q is being phased out, to be replaced by the MMA7361, meaning it will lose the 2 and 4granges.

Atomic IMU 6 Degrees of Freedom - XBee Ready - A versatile 6DOF, can output over a hardwired serialconnection, or wirelessly using XBees

Atomic 6DOF IMU

IMUAccel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


AtomicIMU

6DOF3

±1.5g,2g, 4g,or 6g

3 ±300°/s

Serial,includesXBee

headers

3.3-10VDC

Versatile serialoutput, can bepowered with

any of ourLiPos,

selectableacceleration

range, settableoutput

frequency

6

Pros:

On-board processor is the popular ATmega328, and access to the programming pins is provided if youwant to customize the firmwareInput power is regulated via a 3.3V LDO voltage regulatorThe serial output of this IMU is very versatile. An XBee, a very popular and easy-to-use wirelesstransceiver, can be placed directly onto the IMU giving it a wireless input/output abilities. The serialoutput is also routed to a 6-pin header, which can be interfaced with another microcontroller's UART,an FTDI basic board (to connect it to a computer's USB port), or even one of our Bluetooth Mates(making it bluetooth compatible).Designed to be powered by our line of JST-connected LiPo batteriesUses the MMA7260Q accelerometer, meaning you have four selectable g-ranges


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Very low-price considering what is offeredWell explained datasheet and an example PC program available to interface with the IMUOur firmware allows you to select the output frequency, acceleration range, and output mode

Cons:

Gyros mounted perpendicularly to board may have some inherent errorThe board is relatively largeMMA7260Q is being phased out, to be replaced by the MMA7361, meaning it will lose the 2 and 4granges.

IMU 6 Degrees of Freedom - v4 with Bluetooth Capability - A beast of a 6DOF (9DOF really) withBluetooth output capabilities

IMU 6DOF v4 - Bluetooth Compatible

IMUAccel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


IMU6DOF- v4

3±1.5g,2g, 4g,or 6g

3 ±500°/sBluetoothor Serial

3.3-10VDC

Bluetooth orhardwired output,

3-axes ofmagnetometer,input voltage

regulated,selectable output

frequency

6 (9)

Pros:

The only IMU to feature an ARM processor - the LPC2148 - it has a lot of processing power. If youwant to write your own custom firmware, it can be easily reprogrammedThe sensor board also includes HMC1052x magnetic sensors, which can be used can be used as acompass, providing the IMU's orientation with regard to Earth's magnetic field. This information isincredibly helpful if you need to know a device's exact position.Bluetooth output, wireless is very niceIf you don't want to use the bluetooth, a hard-wired serial interface is also availableUses the MMA7260Q accelerometer, meaning you have four selectable g-rangesIDG500 gyros are really excellent, analog gyrosCan be powered with any of our JST-connected LiPo batteries, or any power source 3.3-16VDCIt's cool looking!

Cons:

The two-stack design is cool-looking, but a little clunky.It's relatively large and expensiveOnly the ±500°/s outputs of the IDG500s are usedMagnetometer outputs are very susceptible to noise over the bluetooth output. If this data is ofextreme importance to you, I'd suggest using the hard-wired interface.


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MMA7260Q is being phased out, to be replaced by the MMA7361, meaning it will lose the 2 and 4granges.

9 Degrees of Freedom - Razor IMU - AHRS Compatible - A brand new, small and inexpensive 9DOF that'sArduino-compatible

9DOF Razor IMU

IMUAccel# ofAxes

Accel Range

Gyro# ofAxes

Gyro Range


9 DOF-

RazorIMU

3 ±16g 3 ±300°/s Serial 3.3-16VDC

Arduino-compatible,

optional AHRScode, 3-axis

magnetometer

9

Pros:

ATmega328 processor includes the Arduino bootloader, so you can easily program whateverfirmware you want onto the IMUWith the work of Jordi Munoz and many others, the 9DOF Razor can become an Attitude and HeadingReference System (AHRS). This enables the 9DOF Razor to become a very powerful controlmechanism for UAVs, autonomous vehicles and image stabilization systems.From the serial output you can choose to interface the 9DOF with another microprocessor, or acomputer via USB, an XBee, or even a Bluetooth.The ADXL345, is top-of-the-line and loaded with featuresLY530AL and LPR530AL combination means no perpendicular mounting of gyros necessaryThe 3-axis HMC5843 is an excellent magnetometer which works great as a compassComparatively, very low-costOn-board reset switch, and ON/OFF control switchOur most recent addition to the IMU categoryCan be powered with any of our JST-connected LiPo batteries

Cons:

The STMicro gyros are more susceptible to drift than their Invensense equivalentsThe shipped firmware is pretty basic, but there is some great example AHRS code availableYou'll need a 3.3V FTDI Basic Breakout to program it as an Arduino

SparkFun's Choices

IMU Combo Board: IMU 6DOF Razor - Ultra-Thin IMU - The fact that it's cheaper than just about allother combo boards, which all actually have fewer features, makes this a pretty easy decision. Thisboard just packs so much punch into a small package, the other combo boards really pale incomparison.

The IMU 5 Degrees of Freedom IDG500/ADXL335 gets runner up here. The IDG500 is afantastic sensor, and we really love the ADXL335. If you can do without that last gyro output,


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you'll save a few dollars going with this board.IMU w/ Integrated Microprocessor: 9 DOF - Razor IMU - It's hard to pick one in this category,because each IMU has it's own stand-out features. However, I think the relatively low-price,cutting-edge sensors, and versatility of the 9DOF makes it really hard to beat.

The market for accelerometers, gyros, and IMUs is rapidly changing. A year or so ago, just the thought of a2-axis gyro was pretty mind-blowing; now we're beginning to see sensors that combine both a 3-axisaccelerometer and a 3-axis gyro into one single chip. Needless to say, we're really excited about what thefuture holds for this category. We'll be updating the list as new sensors become available to us.

Thanks for taking the time to read this, we hope it was informative and made your decision easier. If you haveany questions or concerns, please don't hesitate to add a comment down below, or drop us an email.

Login to post comments.

Dinuka | July 18, 2010 at 1:15 AM 5

This is what I like about SFE. No Crap. They are not afraid to tell us about the cons of their products. Goodtechnical support. My only worry is the high shipping cost to Asian countries like Sri Lanka.

BTW Many thanks for the detailed guide.

Pizzafuchs | November 16, 2010 at 1:59 PM 1

Totally agree! This is an excellent guide, as always at SparkFun :-)

Member53350 | November 30, 2010 at 1:32 AM 2

Can somebody please explain what exactly is a gyro/accelerometer drift ? It is not something you can find inthe datasheeet. I thought it is maybe the error you get when digitally integrating a signal over time, but now Iam not sure.Does anybody know ? help...

dustynrobots | December 3, 2010 at 1:54 PM 2

Great guide! Do you have any preferred references for using the raw data from the accelerometers and gyros(and magnetometers) to get position, velocity, and orientation? I'm guessing the DIY Drones community mighthave some of this done already? I have a commercial IMU unit I can get the raw data from, but theircalculations are "proprietary" - I'm thinking of scrapping that and starting with one of these!

Sam R. | January 1, 2011 at 9:28 AM 1

Its way more fun that way!!


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ExplodingLemur | January 2, 2011 at 12:07 PM 1

Yep, Ardupilot (DIY Drones) would be one reference (they use the Direction Cosine Matrix algorithm),another would be Paparazzi (uses a Kalman filter).

Hm, and I believe there's DCM code for the Razor 9DOF IMU, check that product page.

dustynrobots | February 17, 2011 at 1:37 PM 1

Thanks! I'll have to translate things from UAVs into my biomechanics world, but it looks like most of the workis already done.

ToniK | April 28, 2011 at 1:38 PM 1

Also, check out the firmware for the KinetaMap. It is designed for biomechanical type stuff, so that willprobably help even more.

RocketGeekLyons | January 22, 2011 at 1:28 PM 1

As a high power rocketry enthusiast, these products set me to drooling over the idea of building my idealflight computer. The biggest issues are Z axis maximum G ratings (I need something on the order of100-150G's) and gyro rates (here I need on the order of 3600 deg/sec). The components are getting there, butthe ranges aren't yet. For a UAV, it looks like what is needed is here already, for rocketry - particularly foractive guidance control on a bird pulling 70 G's off the pad it just isn't looking ready yet.

rusteze | March 25, 2011 at 4:35 AM 1

Great guide, very objective considering you're supposed to be salespeople ;) Just noticed the link for yourrecommended IMU Combo Board, IMU 6DOF Razor, points to a depreciated product. You may want toupdate the link to point to the newer version sku:SEN-10010


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Accelerometer and Gyro Buying Guide - SparkFun Electronics

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