As a force sensor supplier, I understand the critical importance of protecting these sensitive devices from shock and vibration. Force sensors are widely used in various industries, including automotive, aerospace, robotics, and medical equipment, where they play a crucial role in measuring and monitoring forces accurately. However, shock and vibration can cause significant damage to force sensors, leading to inaccurate measurements, reduced lifespan, and even complete failure. In this blog post, I will share some effective strategies and techniques to protect force sensors from shock and vibration.
Understanding the Impact of Shock and Vibration on Force Sensors
Before discussing the protection methods, it's essential to understand how shock and vibration can affect force sensors. Shock refers to a sudden and intense impact, while vibration is a continuous, oscillatory motion. Both shock and vibration can generate mechanical stresses on the force sensor, which can cause the following issues:
- Structural Damage: High levels of shock or vibration can cause physical damage to the force sensor's internal components, such as the sensing element, wiring, or housing. This can lead to cracks, fractures, or misalignments, which can affect the sensor's performance and accuracy.
- Electrical Interference: Shock and vibration can also cause electrical interference in the force sensor's circuitry. This can result in noise, signal distortion, or even complete loss of signal, making it difficult or impossible to obtain accurate measurements.
- Calibration Drift: Over time, repeated exposure to shock and vibration can cause the force sensor's calibration to drift. This means that the sensor's output may no longer accurately reflect the applied force, leading to measurement errors and reduced reliability.
Strategies for Protecting Force Sensors from Shock and Vibration
To protect force sensors from shock and vibration, it's important to implement a comprehensive protection strategy that addresses both the mechanical and electrical aspects of the sensor. Here are some effective strategies and techniques that I recommend:
1. Select the Right Force Sensor
The first step in protecting a force sensor from shock and vibration is to select the right sensor for the application. Different force sensors have different levels of shock and vibration resistance, so it's important to choose a sensor that is designed to withstand the specific environmental conditions of the application. When selecting a force sensor, consider the following factors:
- Shock and Vibration Ratings: Look for force sensors that have high shock and vibration ratings. These ratings indicate the maximum levels of shock and vibration that the sensor can withstand without being damaged.
- Construction and Design: Consider the construction and design of the force sensor. Sensors with robust housings, flexible mounting options, and shock-absorbing materials are generally more resistant to shock and vibration.
- Sensing Technology: Different sensing technologies have different levels of sensitivity to shock and vibration. For example, strain gauge-based force sensors are generally more sensitive to vibration than piezoelectric force sensors. Choose a sensing technology that is appropriate for the application.
Some of the force sensors we offer that are designed to withstand shock and vibration include the Flexible Thin Film Pressure Sensor For Stylus Pens SPS01, the Straight Flexible Thin Film Pressure Sensor - 120CM SPF03-120, and the Thin Film Pressure Touch Control Sensor SPB13. These sensors are made from high-quality materials and are designed to provide accurate and reliable measurements in harsh environments.
2. Use Shock and Vibration Isolation Mounts
One of the most effective ways to protect force sensors from shock and vibration is to use shock and vibration isolation mounts. These mounts are designed to absorb and dampen the shock and vibration energy before it reaches the force sensor, reducing the stress on the sensor and preventing damage. There are several types of shock and vibration isolation mounts available, including:
- Rubber Mounts: Rubber mounts are one of the most common types of shock and vibration isolation mounts. They are made from rubber or elastomeric materials and are designed to absorb and dampen the shock and vibration energy through compression and deformation.
- Spring Mounts: Spring mounts use springs to absorb and dampen the shock and vibration energy. They are more effective than rubber mounts at isolating high-frequency vibrations, but they are also more expensive.
- Air Mounts: Air mounts use compressed air to absorb and dampen the shock and vibration energy. They are the most effective type of shock and vibration isolation mounts, but they are also the most expensive and require a compressed air source.
When selecting a shock and vibration isolation mount, consider the following factors:
- Load Capacity: Make sure the mount has a load capacity that is appropriate for the weight of the force sensor and any additional equipment that is attached to it.
- Natural Frequency: The natural frequency of the mount should be lower than the frequency of the shock and vibration that the sensor is likely to encounter. This will ensure that the mount effectively isolates the sensor from the shock and vibration.
- Mounting Options: Choose a mount that has mounting options that are compatible with the force sensor and the application.
3. Secure the Force Sensor Properly
Proper installation and mounting of the force sensor are essential for protecting it from shock and vibration. Make sure the force sensor is securely mounted to a stable surface using the appropriate mounting hardware. Avoid mounting the sensor on surfaces that are prone to vibration or movement, such as motors, pumps, or conveyor belts.
When mounting the force sensor, follow these guidelines:
- Use the Right Mounting Hardware: Use the mounting hardware that is recommended by the force sensor manufacturer. This will ensure that the sensor is properly secured and that the mounting hardware does not interfere with the sensor's performance.
- Tighten the Mounting Bolts Properly: Make sure the mounting bolts are tightened to the proper torque specification. Over-tightening the bolts can cause damage to the sensor, while under-tightening the bolts can allow the sensor to move or vibrate, leading to inaccurate measurements and potential damage.
- Avoid Overloading the Sensor: Do not exceed the maximum load capacity of the force sensor. Overloading the sensor can cause damage to the sensing element and reduce the sensor's lifespan.
4. Shield the Force Sensor from Electrical Interference
In addition to protecting the force sensor from mechanical shock and vibration, it's also important to shield it from electrical interference. Electrical interference can be caused by a variety of sources, including electromagnetic fields, radio frequency interference (RFI), and electrostatic discharge (ESD). To shield the force sensor from electrical interference, consider the following techniques:
- Use Shielded Cables: Use shielded cables to connect the force sensor to the data acquisition system. Shielded cables have a conductive layer that surrounds the inner conductors, which helps to block electromagnetic interference.
- Ground the Force Sensor Properly: Make sure the force sensor is properly grounded to the electrical system. This will help to prevent electrostatic discharge and reduce the risk of electrical interference.
- Use EMI/RFI Filters: Install EMI/RFI filters in the electrical circuit to reduce the level of electromagnetic and radio frequency interference. These filters can be installed at the input or output of the force sensor, depending on the application.
5. Regularly Inspect and Maintain the Force Sensor
Regular inspection and maintenance of the force sensor are essential for ensuring its long-term performance and reliability. Inspect the force sensor regularly for signs of damage, such as cracks, fractures, or loose connections. Check the calibration of the sensor periodically to ensure that it is still accurate.
When inspecting the force sensor, follow these guidelines:
- Visual Inspection: Perform a visual inspection of the force sensor to look for any signs of physical damage. Check the housing, wiring, and connectors for cracks, fractures, or loose connections.
- Electrical Inspection: Use a multimeter or other electrical testing equipment to check the electrical continuity and resistance of the force sensor. This will help to identify any electrical problems, such as short circuits or open circuits.
- Calibration Check: Check the calibration of the force sensor periodically to ensure that it is still accurate. Use a calibrated reference force to compare the output of the sensor to the expected value. If the sensor is out of calibration, have it recalibrated by a qualified technician.
Conclusion
Protecting force sensors from shock and vibration is essential for ensuring their long-term performance and reliability. By selecting the right force sensor, using shock and vibration isolation mounts, securing the sensor properly, shielding it from electrical interference, and regularly inspecting and maintaining it, you can minimize the risk of damage and ensure accurate and reliable measurements.
If you have any questions or need further assistance in protecting your force sensors from shock and vibration, please don't hesitate to contact us. We are a leading force sensor supplier and can provide you with the expertise and products you need to protect your sensors and ensure the success of your application.
References
- O'Connor, T. (2019). Force Sensors: Principles, Characteristics, and Applications. Elsevier.
- Doebelin, E. O. (2003). Measurement Systems: Application and Design. McGraw-Hill.
- Transducer Techniques. (n.d.). Force Sensor Installation and Mounting Guide. Retrieved from [Transducer Techniques Website]