Measuring Vibration? Know Which Sensor to Use

Measuring Vibration? Know Which Sensor to Use

Every object that moves is experiencing acceleration, but not every movement requires one type of accelerometer to measure it. For applications that involve vibration, the type of accelerometer you need depends on the requirements of your project.

Force-balanced accelerometers

Force-balanced sensors are often used to test & control passenger trains

For Low Vibration Sensing

Force-balanced sensors use a pendulum and torque motor and MEMS accelerometers use chip-based technology to measure acceleration in ranges to +/- 40G with a resolution to 1 µg. Some MEMS units have a bandwidth of 400 Hz which means they can be used for low level vibration monitoring, but not higher levels.

The low bandwidth for these accelerometers is intended to prevent outside vibration from interfering with their acceleration readings. The force-balanced sensors are fluid-damped and the MEMS use micro controllers and low-pass filters to keep their frequencies low.

MEMS Accelerometer

A MEMS accelerometer is a low-cost option & includes bandwidths up to 400 Hz

These types of accelerometers can be used on projects such as aerospace or automobile testing, train controls, wind turbine controls and sea state monitoring. If the level of vibration in your project is greater than 400Hz, a different type of accelerometer may be what you need.

For High Vibration Sensing

You may come across a project that includes a higher level of vibration from what a force-balanced or MEMS sensor can offer. When the frequency of your project is greater than 400 Hz, you will need a sensor that is specifically meant for high vibration measurement. Piezoelectric sensors are designed based on the concept that voltage induced by pressure is proportional to the acting pressure. Using this method, the sensor can measure single or repetitive pressures such as vibration.

If your application demands a level of vibration no greater than 400 Hz, a force-balanced or MEMS accelerometer is a useful solution. If you’re looking for more information on which accelerometer is right for your project, talk to us.

Precision Sensors for a Tight Budget

Precision Sensors for a Tight Budget

When developing a new railcar, bridge or construction machine, every movement is a crucial contribution to the success or failure of the project. Implementing precision inertial sensors into the design of a project is a necessity, but with limited resources, short design cycles and tight budgets, engineers are expected to do more with less. High precision sensors typically cost thousands of dollars each, but there are some out there that will run a few hundred bucks a piece, without sacrificing too much precision.

JDI Digital MEMS Inclinometer

JDI Digital MEMS Inclinometer

Economical Sensors for Design Engineers

MEMS sensors can be purchased fully packaged at significantly lower prices than traditional sensors. They aren’t quite as sensitive as traditional sensors (resolution to 0.0001° tilt, 0.04 mg acceleration), but for many OEM and industrial applications, this is sufficient precision.

MEMS accelerometers have high vibration sensitivity (up to 400 Hz), which can be useful for detecting failures within a mechanical design.

 

SMI Emerald Series Inclinometer

SMI Emerald Series Inclinometer

Emerald Series inclinometers and accelerometer (3.5 µrad or 3.5 µg resolution) are higher precision OEM sensors with servo technology and durability (IP65) seal. However, they are not fluid-damped so you’ll want to keep them away from vibration. This series falls under the traditional precision sensor category, but without the steep price tag.

MEMS and Emerald series sensors have a small footprint making them easy to build into a design and they have the precision to serve applications such as construction equipment, industrial automation, solar trackers, platform positioning and automotive testing.

850 MEMS Tuff Tilt

850 MEMS Tuff Tilt

Economical Sensors for Civil Engineers

Civil engineers need a static and weatherproof unit that can be mounted on a bridge, building, dam or platform to track structural integrity. The 850 and 875 series utilize low-cost MEMS technology within weatherproof enclosures providing a geotechnical tilt solution that brings down costs.

Black Diamond 750-050 Tiltmeter

Black Diamond 750-050 Tiltmeter

The Black Diamond 750-050 is much like the Emerald Series in terms of performance and price, but is intended for the geotechnical industry. Most civil engineering tiltmeters have a large footprint, but the Black Diamond (1.55″ W x 3.10” L x 2.04″ H) saves on space.

PCA Boards

PCA Boards

Use a Raw Sensor

If you have the means to construct an enclosure of your own, PCA MEMS boards can be purchased on their own as an easy and affordable tilt sensing option.

Looking for a quote or a custom sensor? Contact us to learn how we can build a solution tailored to your project and budget.

Why Solar Trackers Depend on Inclinometers

The demand for renewable energy has grown as we seek to preserve our planet while harnessing its resources. The solar farm automation market is expected to grow at a compound annual growth rate of 18% between now and 2025 which means more solar farms will be popping up, worldwide.

Many countries are investing in this form of renewable energy and to ensure that they get the largest return on their investment, these panels must be designed and controlled with reliable components.

What a tilt sensor has to do with solar tracking

To harness the sun’s energy at all hours of the day, a solar tracking panel must be able to constantly make subtle movements so that the sun’s rays fall perpendicular to the panel at all hours of the day. A high precision inclinometer (tilt sensor) is necessary within the design of these panels in order to ensure they operate at their best.

With a resolution as small as 1 µradian, a force-balanced inclinometer can be embedded into the base of the panel and provide feedback on its positioning. As the sun moves across the sky, the inclinometer can be used to automate the position of the panel to capture all the solar power it can.

What kind of sensors are useful

A single or dual-axis sensor is ideal for this kind of application. A force-balanced inclinometer will provide high performance and a long lifespan, but if your budget is a big factor, a MEMS sensor has lower precision, but is a suitable, low-cost option. Since this application is static, a gravity-referenced 900 series electrolytic tiltmeter is a highly sensitive and customizable option. To learn more about how these sensors can be implemented into your design, talk to us.

How to Get Tilt Readings from Beneath the Water

You’ve been hired to maintain an iconic bridge that thousands of people need to cross every day. There are plenty of factors to consider and you’ll need to be able to track its stability using precise instruments that will likely have to be plunged into the water, but still provide effective readings.

Shallow Water Tilt Solutions

For inland structures such as a bridge or a dam, you won’t need a heavy duty tiltmeter to get the job done. A lightweight, submersible unit such as the 820 series can be planted down at the base of a structure to provide those must-have readings from the hardest places to reach.

Offshore Ocean Solutions

When you’re looking at a 2,000 meter dive into the ocean to test and measure the stability and performance of a structure such as an oil rig, a heavy duty instrument is the answer. DeepWater tiltmeters come in a rugged housing and can be bolted to deep underwater structures for precise structural feedback.

Undersea geophysical studies such as volcanic activity and fault lines can be monitored with a Lily borehole tiltmeter. NOAA has been using one to monitor the activity of an undersea volcano.

Conclusion

Most landscapes subtly change over time and engineers need to account for this when building and maintaining vital infrastructure. Most tiltmeters are designed to stay high and dry, but there are models built for specific subsea needs, whether they’re in shallow freshwater or extreme offshore depths. Looking for more information or a custom tiltmeter? Talk to a sensor expert.

Why Electrolytic Tiltmeters Must Remain Static

Why Electrolytic Tiltmeters Must Remain Static

Electrolytic tiltmeters are excellent solutions to constantly monitor the structural health of large, important infrastructure or landmasses. They are highly sensitive, low maintenance and have long lifespans. However, they are temperamental to linear motion which is why they should avoid environments where excessive vibration and motion are present.

What happens to a tiltmeter in a non-static environment

Tiltmeters use electrolytic technology which consists of a vial filled with electrolytic fluid. When tilt is applied, the fluid moves and is noticed by pickup electrodes, much like a carpenter’s level.

Since this technology is so sensitive, it can be vulnerable to heavy shock and motion. When this happens, the fluid sloshes back and forth until it settles down. This creates a lot of squiggly lines on your datalogger and can take up to several minutes to level out and provide the readings you need.

A Tuff Tilt 420 tiltmeter monitors the Huey P. Long Bridge in New Orleans, LA

Which applications are right for electrolytic tiltmeters

Tiltmeters live in static environments such as the pier of a bridge or on the surface of a volcano. Since these places do not rattle or move around, the sensor will detect vital tilt measurements. For instance, when an earthquake strikes a bridge, you will have to wait until the phenomenon is over and the readings settle to determine if that event caused the bridge to move.

Which applications won’t work

If there is linear motion, there will be interference in the readings. Some OEM applications such as construction machinery or military equipment can include constant movement and vibration. In these cases, most force-balanced inclinometers are designed to filter out noise and vibration and will likely be the solution you need.

For additional questions or to learn about how to order a custom inclinometer, talk to a sensor expert.

3 Examples that Reveal How Important Inclinometers are for Construction Vehicles

Inclinometers for Construction Vehicles

Construction machines need to function with efficiency and safety, and an inclinometer is a vital component to control how they operate. Here are three examples of how construction manufacturers can use inclinometers to create a fine-tuned rig.

1. Road Profiling

A smooth, comfortable ride on a newly paved road is an expectation. In order to ensure the road is laid out this way, road rollers are responsible for leveling out fresh pavement. An inclinometer can be embedded into a roller to provide feedback to the operator on the levelness of the pavement as the roller does its job.

For sharp curves in spots such as on and off ramps, superelevation is necessary to prevent a passenger car’s momentum from carrying it off the road. Engineers can determine the angle needed for this and use an inclinometer to verify the superelevation is properly implemented.

Inclinometers for Road Rollers

2. Leveling a Mobile Crane

A stable base is critical for the safety of a mobile crane as it reaches lofty structures. When the legs of a crane are deployed, it needs to rely on a system to level itself in order to function without running the risk of leaning too far. An inclinometer can be implemented into this leveling system to automate and control the position of the crane.

Another important place an inclinometer can be located is on the boom of the crane. The sensor can provide feedback to the operator on the positioning of the boom so that heavy objects can be placed effectively.

Inclinometers for Mobile Cranes

3. Controlling a Mining Shovel

A mining shovel needs to move a lot of dirt and rock in a day’s work. With a precision measurement system, the shovel’s arm can be controlled to make sure those piles of rocks are plopped in the right spot.Inclinometers for Mobile Cranes

Tilt Solutions for Environments with High Shock & Vibration

A force-balanced inclinometer is a highly accurate tilt solution with a resolution as fine a 1 microradian. Most models are fluid-damped, which means if there is a lot of surrounding noise and vibration, the sensor will filter that out from its readings.

Lower Cost Tilt Solutions

If you’re on a budget and need to buy in bulk, a MEMS inclinometer is sufficient for construction rigs too. With a resolution to 0.0001°, the precision is not as great as a force-balanced sensor, but if the application doesn’t need that extra precision, this is the solution for you.

Do you need something more than a standard sensor? Chat with us and we’ll work with you to develop a custom solution.

3 Important Facts About Using A MEMS Sensor

3 Important Facts About Using A MEMS Sensor

You need relatively high precision to monitor and measure the movement of your machine, but you only have so much money in the budget. In this world of doing more with less, MEMS (micro electro-mechanical system) sensors can be the solution for plenty of industrial projects, not just cell phones.

1. Great Solution for a Limited Budget

A MEMS sensor will be a lower cost solution as opposed to traditional, higher precision sensors. For applications that require high volume and lower precision, such as construction machines, MEMS will fit in just fine.

2. Dynamic & Precise Performance

They can also offer a wider range (+/-90º, +/-40G) and dynamic response up to 400Hz which can be useful for some vibration measurement.

With a resolution up to 0.0005º, some models are even catching up to higher precision sensors. The 850 Tuff Tilt is a field-ready tiltmeter that uses low cost MEMS technology, but with the precision to measure small geotechnical movement such as a bridge or a tunnel. The JMA-165 is a precise and certified economical alternative for rail transportation measurement. This MEMS sensor has the precision to control the motion of metro trains and test the speed of commercial passenger trains.

Some models are getting even more robust. The JDI-100/200 digital MEMS inclinometer offers full temperature compensation across all measuring ranges which enables the it to perform to 0.005° accuracy.

3. The Limitations of MEMS Technology

You’ll free up some space in your budget, but may have to make a sacrifice too. MEMS has a larger drift over temperature which can be a concern for those who don’t have temperature compensation or heating capabilities. Relative to other traditional sensor technology, MEMS generally has lower precision, but if you don’t need to measure something in increments of micro radians or micro g’s, MEMS will suffice.

What They’re Used For

MEMS has matured to serve not just cell phones anymore. The industrial market, including construction and agricultural OEM’s can implement a MEMS-based sensor into their machinery to measure and control the positioning of the machine’s tools for optimum performance. They can also be used for platform leveling for mobile cranes and radar as well as testing in the laboratory or classroom. If you’re still looking for a tilt or motion solution for your project, talk to a sensor expert.

2 Reasons Why A Force-Balanced Sensor Works for Your Project

2 Reasons Why A Force-Balanced Sensor Works for Your Project

Your project needs the precision to monitor movement as fine as 1 µG or µradian, but there will also be a lot surrounding noise and vibration that you don’t want to interfere with your readings. If you’re working on something like this, a sensor with force-balanced (also known as servo) technology is the answer and here is why.

1. Precise Performance that Holds Up to Harsh Environments

Force-balanced sensors have a strong dynamic response (as much at 200 Hz for some models) and diverse measuring ranges, up to +/-90° for inclinometers and +/-20G for accelerometers. They come in rugged enclosures with mechanisms that are designed to filter shock and vibration from readings. They can also be fluid-damped to alter the vibration and noise resistance and have low thermal drift.

2. Some Models Can Help When On A Budget

Emerald Series Sensors

Emerald Series Sensors

MEMS sensors have been competing against force-balanced technology, mostly due to their lower cost. However, some models can match or even beat the price of some MEMS without sacrificing precision. The Emerald series inclinometers and accelerometers are the low-cost version of force-balanced sensors. They are not fluid-damped, but beat MEMS with higher precision while hitting similar price points.

What They’re Used For

With rugged enclosures, high temperature and vibration resistance, these sensors can be placed in plenty of environments. They are typically used for OEM projects such as military, rail transportation, construction, agricultural and industrial equipment. With their fine precision they can also be used for testing and research within the aerospace, automotive and academic worlds. Are you curious to know if a force-balanced sensor is the answer for your project? Talk to a product expert.

3 Reasons To Consider Using An Electrolytic Tiltmeter

3 Reasons To Consider Using An Electrolytic Tiltmeter

The world is evolving and so are the many different ways you can take precision tilt measurements. However, there are few sensor technologies that can cover all applications and you need to know which is the right one for your project. For many civil engineering and geophysical projects, electrolytic technology has been the answer and this post will explain why.

1. Extreme Sensitivity       

Electrolytic sensors are some of the most sensitive in their market with a resolution as fine as 2.5 nanoradians. If you string a rope from New York City to San Francisco and lift one end up by 10 mm, that’s an angle of 2.5 nanoradians.

2. Long Lifespan       

Since electrolytic sensors are based on carpenter level-like technology, there are few mechanical parts involved. With these few parts, the sensor is less likely to break down over time. Some sensors have been known to be active for over 20 years.

3. Most Models Are Weatherproof       

Many sensors require an enclosure to be built around them so they can survive harsh temperature and shock environments. Some electrolytic models, such as the Tuff Tilt series, come in a rugged enclosure to protect the sensor from tough conditions. This means it is field-ready and you won’t need to build something around it for protection. Just mount it, and leave it.

Limitations of an Electrolytic Tiltmeter

While some models are built to survive the elements, the added enclosure makes for a larger footprint.

Some models can be a bit temperamental too. These sensors have a low frequency response, which means they should be mounted to be stationary and upright to make small, gradual measurements, which is great for monitoring the activity of a structure or embankment.

What They’re Used For

With large footprints, durability and sensitivity, electrolytic tiltmeters make great solutions for many geophysical and geotechnical projects. The durability allows them to be set on a bridge, a dam or building where weather will be a factor. Some models are submersible to 3500 psi for deep subsea measuring and some are rated to be buried into boreholes for slope stability studies, volcano monitoring and many other geophysical studies.

If a geotechnical or geophysical project is what you’re working on and you need to know if there is movement involved, check out an electrolytic tiltmeter. Need something more than what you see? Talk to us about custom sensors.

Determining the Right Cable Length and Output for a Sensor

Determining the Right Cable Length and Output for a Sensor

If you’re monitoring a bridge or automating a machine, a high precision sensor is a great solution, but it’s no good if the output signal can’t reach the data logger. Depending on what you need to measure and what environment you’re in, determining how long your cable must run can be crucial.

High precision sensors offer three common output types: analog, digital and current and each one can serve a certain purpose based on your application

Capabilities of Voltage Output

Analog output is typically used for applications that do not require long cable lengths since voltage is susceptible to noise interference from vibration and RF waves. A thicker, shielded cable can be used to resist noise and allow cable lengths to run to 50 feet or more. This comes in handy for industrial manufacturing applications where is longer cables are needed, but there is a lot of outside movement and vibration. Some standard options are 0-5, ±5V, 0-10V, ±10V or 0.5-4.5V

Features of Current Output

Current output is more immune to outside interference which means it can run through cable lengths of 4,000+ meters. For really long lengths, a shielded cable may be necessary to resist outside noise and vibration. This is used for putting a sensor in hard to reach places such as structural monitoring, retaining walls, slope stability, volcano studies and platform leveling and positioning. The standard option is 4-20mA output.

Assets of Digital Output

Digital output can provide a variance of cable lengths based on which signal is used. The maximum length for RS232 output is 15 meters, which is fine for industrial automation and testing. RS422 and RS485 are capable of up to 1,000 meters of cable distance giving you more ability for things like structural monitoring. Other options are also available for some models, such as UART TTL and Ethernet interface.

Which sensors offer these output options?

Many sensors offer multiple output options so that you can use the specifications of one model, but with the choice of two or three output types. Force balanced sensors that offer more than one output option include the LCF-2330, LCF-300, RMI, SMI, LSOX, DXI and DXA. MEMS sensors offer analog, current and digital output types as do the 700 series, 800 series and 900 series electrolytic tiltmeters. Most Jewell sensors can also be customized for specific applications. Contact us to learn how.