Method and apparatus for testing material strengths

An apparatus for the nondestructive evaluation of strength remaining in a wooden article, comprising:

• a frequency sweeping waveform generator that generates a sinusoidal waveform and which sweeps frequencies between a low frequency and a high frequency while evaluating the strength of a material, wherein the low frequency is from about 10 Hz to about 150 Hz, and the high frequency is from 6,000 Hz to about 24,000 Hz;
• a driver for transmitting the frequency sweeping waveform into an elongated wooden article, the driver being electronically coupled to the waveform generator and coupled to the wooden article at a drive point;
• a force sensor that is coupled to the elongated wooden article at or adjacent to the drive point for measuring force transmitted into the wooden article as the waveform sweeps between the low and the high frequencies;
• a first accelerometer that is coupled to the material at or substantially adjacent to the drive point for measuring response of the wooden article to the transmitted waveform as the waveform sweep between the low frequency and the high frequency;
• a second accelerometer that is coupled to the article at a point that is substantially diametrically opposed to the drive point for measuring response of the wooden article to the transmitted waveform as the waveform sweeps between the low frequency and the high frequency;
• and
• a microprocessor that receives signals from the sensor and accelerometers and evaluates material strength based on the signals from the force sensor and the accelerometers as the waveform sweeps between the low and the high frequencies.

A manually transportable apparatus for the nondestructive evaluation of material strength remaining in in-service utility poles, the apparatus comprising:

• a waveform generator that comprises either (1) a sinusoidal frequency sweeping waveform generator that sweeps frequencies between a low frequency and a high frequency while evaluating material strength remaining in a utility pole, wherein the low frequency is from about 10 Hz to about 150 Hz, and the high frequency is from about 6,000 Hz to about 24,000 Hz or (2) a pseudo random waveform generator that continuously generates a waveform within the frequency range of from about 150 Hz to about 6,000 Hz during evaluation of material strength remaining in a utility pole;
• a driver for transmitting the waveform into the utility pole, the driver being electronically linked to the waveform generator and mechanically coupled to the pole at a drive point;
• a force sensor that is mechanically coupled to the driver and to the pole at or adjacent to the drive point for measuring force transmitted into the pole as the sinusoidal waveform generator sweeps frequencies between the low and the high frequencies or the pseudo random waveform generator generates a waveform within the frequency range;
• a first accelerometer that is coupled to the pole at or adjacent to the drive point for continuously measuring response of the pole to the (1) waveforms of frequencies sweeping between the low frequency and the high frequency that are transmitted to the pole by the driver, or (2) a waveform within the range of from about 150 Hz to about 6,000 Hz, that is transmitted to the pole by the driver;
• and
• a microprocessor that receives signals from the sensor and accelerometer and evaluates strength of the pole based on the signals from the force sensor and the accelerometer as (1) the sinusoidal waveform generator sweeps frequencies between the low and the high frequencies, or (2) the pseudo random waveform generator generates a waveform within the frequency range.

A method for testing the strength of a material, comprising:

• coupling a force sensor and a first accelerometer to a material;
• transmitting into the material at a drive point, while testing the strength of the material, either (1) a sinusoidal waveform having a frequency that, during a testing operation, continuously sweeps between a low frequency and a high frequency, wherein the low frequency is from about 10 Hz to about 150 Hz and the high frequency is from about 6,000 Hz to about 24,000, or (2) a pseudo random waveform within the frequency range of from about 150 Hz to about 6,000 Hz;
• measuring force transmitted into the material at a point at or substantially adjacent to the drive point using the force sensor;
• measuring response to the transmitted waveform by the material using the first accelerometer as (1) the frequency sweeps between the low frequency and the high frequency, or (2) the pseudo random waveform is transmitted to the material;
• and
• evaluating strength remaining in the material based on the signals from the force sensor and the first accelerometer as (1) the frequency sweeps between the low and the high frequencies, or (2) the pseudo random waveform is transmitted to the material within the frequency range.

A nondestructive method for testing the strength remaining in a utility pole, the method comprising:

• coupling a force sensor to the pole at or adjacent to a drive point;
• coupling a first accelerometer to the pole at or adjacent to the drive point;
• coupling at least a second accelerometer to the pole at a position that is substantially diametrically opposed to the drive point;
• transmitting into a utility pole at the drive point either (1) a sinusoidal waveform having a frequency that can sweep from a low frequency to a high frequency, wherein the low frequency is from about 10 Hz to about 150 Hz and the high frequency is from about 6,000 Hz to about 24,000, or (2) a pseudo random waveform within the frequency range of from about 150 Hz to about 6,000 Hz;
• and
• inputting digitized outputs from the force sensor and accelerometers into a neural network model to determine the strength remaining in the pole.