amyfolkestad@hotmail.com, Author at Innosolve

Infrared Image Analysis

Posted on February 20, 2019February 28, 2019 by amyfolkestad@hotmail.com

I recently transplanted a Blue Spruce tree on my property. I use a red garden hose from my house to water the tree. I use an automatic water timer to water the tree. The automatic water timer waters at noon and midnight every day. I am away at work at noon and sleep at midnight. I need to verify that the tree is receiving water. The purpose of this post is to verify that the transplanted tree is receiving water.

Thermal Analysis

The physical process of evaporation causes surfaces to cool. At 8:15pm on 6/7/18, I utilized my FLIR One Pro infrared camera to capture a visible light and infrared image of my transplanted tree. The emissivity of trees is generally around .98 so the camera was set to this value. It is reasonable to believe that the emissivity of grass will be similar to the tree because they are both organic plants. An emissivity setting of .98 is reasonable in the infrared image shown because the garden hose is made of rubber with
a high emissivity and there are no sharp changes in apparent temperature in the image as the garden hose interacts with the grass vegetation. The reflected background temperature was determined to be 32.2 degrees Fahrenheit. The tin foil used to determine the reflected background temperature is visible in the infrared and visible light image. The tin foil has a very low inherent temperature due to its low emissivity and reflective nature.

Infrared Analysis Results

The results of the infrared imaging analysis suggest that the tree is receiving water. Evaporative patterns can be observed along the base of the tree. In fact, it appears that too much water is being supplied to the tree because evaporative patterns can be observed in the image running downhill. Corrective action is to reduce the amount of water being supplied to the tree.

Dual Slope Shutter

Posted on February 20, 2019June 18, 2019 by amyfolkestad@hotmail.com

If you have ever tried to image a high speed explosion you have probably encountered image saturation. Due to the high dynamic range of an explosion event your camera is almost guaranteed to saturate. Saturation is when the range of values a pixel can register, 0 to 255 for the 8-bit case, reach their highest value of white and can do longer gather information. Most attempt to solve the saturation problem by closing their camera’s aperture as far as possible. However, now they have no image until the explosion occurs and can still saturate the image.

Solving saturation with dual slope shutter

One way InnoSolve solves the saturation problem is by using a dual slope shutter. The effect of a dual slope shutter can best be explained by example. The image below shows 5 different firings of an ABRIMS tank main gun. All firings were sampled at 100,000 frames per second using a Photron SA-Z.

InnoSolve Solutions

The firing in the lower left was acquired using no dual slope shutter. All other firings were acquired using various levels of dual slope shutter, UV filtering, and camera fan settings. The impacts of the camera fans and UV filtering will not be discussed in this post. Notice how saturated the fireball becomes. Significant amounts of information is being lost due to the saturated image. This does not have to be the case. For example the upper left image was acquired with 99% dual slope shutter and preserves nearly all the information contained in the fireball. InnoSolve readily uses dual slope shutter capabilities to deploy our quantitative imaging techniques.

Oscillator Quantitative Imaging Harbor Freight vs Rigid

Posted on February 12, 2019June 18, 2019 by amyfolkestad@hotmail.com

Oscillator tools have become the go to tool for just about everything around the house. From cutting drywall to cutting baseboard, oscillator tools are perfect for the job due to their ability to rapidly oscillate between tiny cutting strokes.Many have undertaken the task of comparing the many oscillator tools on the market through product testing. This post will not attempt to reproduce that work. Instead, this post will leverage InnoSolve’s competence in quantifying video.

Frequency and Cutting Stroke

We will be comparing the frequency of oscillation and cutting stroke angle of two popular oscillator tools with the help of Digital Image Correlation (DIC) technology.Oscillator tools oscillate at about 20,000 cycles per second. This equates to about 333 Hz. If you wish to see an oscillator tool frozen in time you can sample a functioning oscillator tool at 333 frames per second (fps). However, a frozen oscillator tool is not very interesting so you probably want to sample at a rate that is at least 10X faster than 333 fps or 3,330 fps. 3,300 fps did not seem sporty enough for this post so we recorded at 16,200 fps. The photogrammetry targets were attached to the head of each tool without a blade in the analysis video. Photogrammetry targets were included on each tool’s body so that rigid body motion due to each hand could be taken into account.

Chicago Electric vs Rigid

The two oscillator tools show cased in this post are made by Chicago Electric and RIDGID tools. The Chicago Electric tool can be found at Harbor Freight Tools and costs about $20. This tool does not advertises an angle of oscillation. The RIDGID oscillating tool was purchased from Home Depot for about $80. This tool advertises 4 degrees of cutting stroke at 20,000 revolutions per minute (rpm).From just looking at the high speed video, it is difficult to accurately quantify how fast and at what angle of oscillation these tools function. Recording the two tools in operation side-by-side is a little better for comparison purposes but still lacks quantization. However, when DIC is applied to track the photogrammetry targets, the angle of oscillation and frequency of oscillation can be easily quantified.

DIC Analysis

From the DIC analysis, the Chicago Electric tool oscillates 3 degrees and the RIDGID tool oscillates a little more than the advertised 4 degrees. From looking at the time scale at 0.016 and 0.026 seconds, 4 oscillations of the Chicago Electric occur over the 0.01 second interval. This equates to 400 Hz or 24,000 rpm. In comparison the RIDGID tool completes 5 cycles from 0.01 to.026 seconds. This equates to 313 Hz or 18,750 rpm.In summary the Chicago Electric tool has a smaller cutting stroke than the RIDGID tool but the Chicago Electric tool operates at a faster rpm.