Description:Field of Invention
These systems are designed for test beds of motors like (BLDC, etc.) and other engines. They use strain gauges to measure thrust without requiring major structural modifications. And modification in the design of Thrust Measuring Bed.
Background of the Invention
In various industries, particularly in aerospace, automotive, and manufacturing, the measurement of thrust is crucial for ensuring the performance, safety and efficiency of engines, motors, or mechanical systems. Thrust measurements are essential for evaluating the effectiveness of propulsion systems, as well as optimizing designs for performance, efficiency, and safety. Traditional thrust measurement techniques often rely on separate, bulky test rigs or complex instrumentation, which can be costly, time-consuming, and large in scale.
Brushless DC (BLDC) motors are widely used in various applications, including drones, electric vehicles, robotics, and industrial automation. Small industries, research institutions, and hobbyists often rely on BLDC motors for propulsion and actuation due to their high efficiency, reliability, and precise speed control. However, accurately measuring the thrust generated by these motors is essential for performance optimization, motor selection, and system design.
Traditional thrust measurement setups are often complex, expensive, and require specialized laboratory-grade equipment, making them inaccessible to small industries and hobbyists. Many available solutions use strain gauge-based load cells or complex mechanical structures, which can be cumbersome to set up and calibrate. Additionally, existing solutions may not be designed to accommodate the varying sizes and power levels of BLDC motors used in small-scale applications.
To address these challenges, there is a need for a compact, cost-effective, and easy-to-use thrust measuring bed that can provide accurate thrust readings for BLDC motors. Such a system should allow users to test different motor-propeller combinations under controlled conditions, log performance data, and make informed decisions regarding their applications.
The present invention aims to develop a thrust measuring bed tailored to the needs of small industries, researchers, and hobbyists by offering a user-friendly, affordable, and modular design. This system will enable precise thrust measurement while maintaining simplicity and reliability, thus bridging the gap between high-end industrial setups and DIY experimentation.
The idea has been developed from the existing designs and methods employed to measure thrust. For instance, S. Swearingen in patent US3828610A describes a method for measuring and controlling axial thrust in rotating machinery using thrust bearing assemblies. It works by monitoring the pressure of lubricant forced between the mated faces of fixed and rotating components, and calculating thrust based on pressure differentials either within a single bearing or between opposing bearings. The system can include pressure sensors and a separate balancing mechanism—manual or automatic—to adjust thrust in real time. This innovation is especially useful in high-speed machines like compressors, turbines, and pumps, where thrust variations can lead to bearing failure.
Measuring Axial Pump Thrust apparatus for measuring the hydraulic axial thrust of a pump under operation conditions was proposed by Bernard P. Suchoza and Imre Becse in patent US4782696A describes an apparatus designed to measure the hydraulic axial thrust of a pump operating under high-pressure and high-temperature conditions, such as those found in nuclear reactors. The system works by using a non-rotating elongate rod that applies axial force to a rotating impeller via a retainer bolt, lifting it off its thrust bearing. This force, measured with electronic sensors, corresponds to the actual axial thrust generated during pump operation. The apparatus includes heat dissipation features to protect sensitive measuring components and offers a more accurate thrust measurement than previous room-temperature methods.
The Thrust Measuring Apparatus for measuring axial thrust in a rotary shaft was proposed by Henry F. D. Davis in patent US1998450A outlines a thrust measuring apparatus designed to accurately gauge axial thrust on rotating shafts, particularly in ship propeller systems. The invention uses a radially tapered annular spring positioned between a thrust bearing and a cover plate, where even slight deflections caused by shaft thrust are amplified and measured. These deflections are detected via variable capacitors whose changes in capacitance correspond to the spring’s movement, allowing precise thrust readings. The system avoids the need for bulky motors or oil pumps, making it practical for sea-going vessels and adaptable to both electrical and mechanical measurement methods.
Thrust Measurement System for measuring thrust in a gas turbine engine was proposed by The Boeing Company in patent US20040111957A1 describes a water blended fuel composition designed to reduce nitrogen oxide (NOx) emissions in combustion systems. The invention combines a normally liquid hydrocarbon fuel, water, and a nitrogen-free surfactant, which stabilizes the emulsion without contributing to NOx formation. This composition is suitable for use in both open-flame burners and internal combustion engines. By eliminating nitrogen-containing surfactants typically found in commercial blends, the fuel helps meet stricter emission standards. Optional additives like acids, cetane improvers, and antifreeze agents may be included to enhance performance, and the fuel can exist as a water-in-oil emulsion or micro-emulsion with finely dispersed water droplets.
Thrust Measuring Apparatus for measuring thrust in a propulsion system was proposed by an unknown inventor in patent US20110132056A1 introduces a pressing device for bending pipes that simplifies the structure and reduces the size of conventional bending systems. The invention features a pipe held between a stationary bending die and a clamping die that revolves around it to perform the bend. During this process, an axial compression force is applied to the pipe using a movable table equipped with two cylinders—one pressing the rear end of the pipe and the other pressing the fixed side in the opposite direction. This dual-cylinder setup ensures uniform compression, minimizes wall thinning during bending, and enhances the precision and efficiency of the operation.
Thrust Measuring Device for aircraft engines, a device for measuring the thrust produced by aircraft engines was proposed by an unknown inventor in patent US20130283956A1 describes a bracket assembly designed to securely attach a shift cable connector to a vehicle transmission. The bracket includes two sections: a stationary first section with a groove to receive the connector, and a pivotable second section that locks the connector in place when closed. This secondary locking feature ensures reliable engagement and easy removal when needed, enhancing durability and serviceability. The invention is particularly useful in automatic, dual-clutch, and hybrid transmissions, where precise cable positioning is critical for selecting driving modes like Park, Reverse, or Drive.
Thrust Measuring Device for Marine Propulsion Systems device for measuring the thrust produced by marine propulsion systems was proposed by an unknown inventor in patent US20150107234A1 details a boom driving apparatus for construction machines like hydraulic excavators that reduces power consumption during excavation. The system includes a boom cylinder, a variable-displacement hydraulic pump, and a control valve that directs hydraulic oil to the cylinder. A key innovation is the use of sensors and a controller that detect when excavation forces naturally extend the boom cylinder, even without active oil supply. In such cases, the apparatus blocks oil flow and reduces pump output, conserving energy. This smart hydraulic control enables efficient boom operation during combined movements like boom raising and arm crowding, minimizing engine load and improving fuel economy.
US5465617A discloses a method for improving air/fuel ratio control in internal combustion engines by enhancing the accuracy of cylinder inlet air rate measurement. The invention combines data from a mass airflow sensor with a speed-density model to correct for bias errors caused by changing conditions like temperature, altitude, and exhaust gas recirculation. A correction term is periodically updated during steady-state engine operation and applied during transient conditions to refine volumetric efficiency estimates. This approach enables more precise fuel delivery, helping maintain a stoichiometric air/fuel ratio and improving emissions control through catalytic treatment.
Thrust Measuring Device for Electric Motors apparatus for measuring the hydraulic axial thrust of a pump under operation conditions was proposed in US4782696A which describes an apparatus for measuring the hydraulic axial thrust of a pump operating under high-pressure and high-temperature conditions, such as those found in nuclear reactors. The system uses a non-rotating elongate rod that applies axial force to a rotating impeller via a retainer bolt, lifting it off its thrust bearing. This force—measured using electronic sensors like load cells and displacement transducers—corresponds to the actual axial thrust generated during pump operation. To ensure accurate readings, the apparatus includes heat dissipation features that protect sensitive components from the hot fluid being pumped. This design allows for real-time thrust measurements under operational conditions, improving reliability over traditional room-temperature testing methods.
Summary of the Invention
The invention of the thrust measuring bed with a strain gage is designed to accurately measure the thrust produced by aero-engines.
The system is designed to improve loading stability, loading efficiency, thrust measurement accuracy, and thrust calibrating accuracy compared to previous methods. It can be applied to various platforms for thrust loading, calibrating, and measuring.
Brief Description of Drawings
The invention will be described in detail with reference to the exemplary embodiments shown in the figures wherein:
Figure 1: Nomenclature of thrust measuring bed
Figure 2: All Views of thrust measuring bed
Detailed Description of the Invention
The base serves as the foundation of the entire system. It is designed to provide stability and support for all other components, ensuring accurate measurements. The base is typically made from a durable material that can withstand the forces generated during testing (1).
With reference to figure 3, the components of Thrust Measuring Bed presented in the front view. This indicates

 Base Plate (1)
 Linear Bearing (2)
 Motor Base (3)
 Strain Gage (4)
 Motor (5)
 Propeller (6)
 Screw (7)

Linear bearings are crucial for enabling smooth and precise linear motion. They reduce friction and wear, allowing the moving parts to glide effortlessly. This ensures that the thrust measurement process is accurate and repeatable (2). The motor base is a dedicated platform that securely holds the motor in place. It is designed to minimize vibrations and maintain alignment, which is essential for accurate thrust measurement (3). The strain gage is a sensor that measures the strain (deformation) in the system. When the engine or propeller generates thrust, the strain gage detects the minute changes in shape and converts this data into an electrical signal. This signal is then used to calculate the exact thrust produced. Strain gages are highly sensitive and can detect very small changes, making them ideal for precise measurements (4). The motor is responsible for driving the propeller, simulating the thrust produced by an aero-engine. It is selected based on the required power and torque specifications to ensure it can generate the necessary thrust for testing purposes (5). The propeller is driven by the motor and generates thrust when it rotates. Different propeller designs can be used to simulate various engine configurations and performance characteristics. The propeller's performance is critical to the accuracy of the thrust measurement (6). Screws are used for adjustments and securing components in place. They allow for fine-tuning of the system to ensure all parts are aligned correctly and operating at their optimal performance levels (7).
A thrust measuring device is a specialized instrument used to quantify the axial force generated by engines, motors, or propulsion systems. This force—commonly referred to as thrust—is essential for evaluating performance in aerospace, automotive, marine, and industrial applications. The device plays a critical role in validating propulsion efficiency, ensuring safety, and guiding design improvements.
At the heart of most thrust measuring devices are load cells or force sensors, which convert mechanical force into electrical signals. These sensors are often strain-gauge (4) based and calibrated to detect subtle variations in force. The engine or motor under test is mounted on a rigid frame that isolates thrust from other mechanical influences such as torque, vibration, or lateral forces. This isolation ensures that the readings reflect pure axial thrust without contamination from unrelated dynamics.
The data acquisition system is another vital component, capturing real-time thrust data with high sampling rates. These systems may include analog, digital, or frequency outputs and are often paired with software interfaces that provide graphical visualization, unit conversion, and reporting tools. Advanced setups also incorporate temperature compensation and overload protection to maintain accuracy under extreme operating conditions.
Different types of thrust measuring devices are tailored to specific use cases. For example, pendulum thrust stands are widely used in electric propulsion labs to measure micro-Newton to milli-Newton thrust levels. These stands rely on the deflection of a pendulum arm caused by thrust, which is then translated into force measurements. In contrast, rotary thrustmeters are designed for rotating shafts in industrial motors and turbines, while hydraulic load cell setups are used in heavy machinery environments where high-force measurements are required.
Calibration is a cornerstone of thrust measurement accuracy. Devices often feature bi-directional shunt calibration or in-situ calibration using known weights or forces. This ensures that the system maintains fidelity across different operating conditions, including transient and steady-state phases. Engineers may also fine-tune control loop settings to adapt to varying load conditions, minimizing oscillations and offset errors.
Thrust measuring beds play a vital role across multiple sectors by enabling precise evaluation of propulsion systems. In the aerospace industry, they are essential for testing aircraft and rocket engines, ensuring optimal performance and flight safety. These beds allow engineers to fine-tune thrust outputs and validate engine reliability under simulated conditions. In the automotive sector, thrust measuring beds contribute to enhancing vehicle performance by assessing engine efficiency and supporting improvements in fuel economy and mechanical output. Their application extends to industrial settings, where they help monitor the thrust generated by machinery, ensuring operational efficiency and equipment reliability. In research and development, thrust measuring beds serve as critical tools for testing emerging propulsion technologies, fostering innovation and advancement in propulsion science. They provide a controlled environment for experimenting with novel designs and materials, accelerating progress in engineering solutions. The military also relies heavily on thrust measuring beds to evaluate propulsion systems used in aircraft, missiles, and other defense equipment. This ensures that military-grade engines meet stringent performance and safety standards before deployment. Overall, thrust measuring beds are indispensable in optimizing propulsion systems, enhancing performance, and driving innovation across aerospace, automotive, industrial, research, and military domains.
In summary, thrust measuring devices are indispensable tools for propulsion system characterization. They provide objective performance metrics that inform design decisions, enhance fuel efficiency, and support environmental sustainability. Whether used in spacecraft testing, drone motor calibration, or automotive transmission analysis, these devices enable engineers to push the boundaries of propulsion technology with precision and confidence. , Claims:The scope of the invention is defined by the following claims:
Claim:
1. A thrust measuring bed:
a) A base plate (1) attached to a linear bearing (2) mounted on the base with the holes made on it.
b) A strain gauge (4) one end is attached to a base plate (1) another end is attached to the motor base (3).
c) A motor base (3) is attached to the motor (5) along with the screw (7).
d) A propeller (6) is attached to the motor (6).
2. According to claim 1, A strain gauge (4) is a sensor used to measure the amount of strain—essentially deformation—experienced by an object when subjected to external forces.
3. According to claim 1, A linear bearing (2) is a mechanical component designed to facilitate smooth, low-friction motion along a straight path.
4. According to claim 1, A propeller (6) is a mechanical device used to generate thrust by converting rotational motion into linear force, propelling vehicles like boats and aircraft through water or air.
5. According to claim 1, A motor (5) is a device that converts electrical energy into mechanical energy, typically through the interaction of magnetic fields and electric currents.
6. According to claim 1, A base plate (1) is a flat, typically rectangular aluminium plate used at the bottom of structural elements like columns, posts, or machinery to distribute loads and provide stability.