Z. Zhau et al. presented a sweep scan path generation system which uses less dynamic rotary head of 5-axis CMM to inspection of random free form surface. The method involves an algorithm to generate sweep scan path, in which two rotary axes are fully utilized to cover free form surface area with number of sweep along the guideline provided by user. The method is validated by three comparison experiments on different types of surfaces with sweep scan path from algorithm and existing zigzag method. The sweep scan method gives more scanning efficiency than zigzag method with smooth movement of CMM axes. However, the method required significant user involvement and sweep scan path is mainly depends on the guideline provided by user.
S. M.
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The deviation and approximation error will get add up to the measurement errors due to less number of points.
Grzegorz Krajewski and Adam Wo´zniak proposed a method to determine dynamic error of CMM by scanning simple shape master artifact. The artifact is assembly of two flat plates with provision to adjust the angle between the plates. The experiment is carried out on ZEISS ACCURA Bridge CMM with VAST XXT (Passive) scanning probe and VAST Gold (Active) scanning probe. The dynamic error is determined by scanning the plate parallel to the scan axis first then the plate inclined at some angle. The sudden change in direction causes acceleration which leads to dynamic errors. At high scanning speed, the dynamic error is more in passive probe than active probe. The proposed method can also use for optimization of measurement process.
Giovanni Moroni and Stefano Petrò proposed a model to evaluate inspection cost and optimal inspection strategy by optimization of model. Optimal sampling strategy is based on calibrated artifact approach and simulation based approach. These strategies are applied on three case studies of which two for roundness and one for parallelism. These approaches give cost effective optimal sample size. Artifact based approach is easier to apply, but calibrated artifacts can increase cost. Simulation based approach does not require any artifact and gives task specific uncertainty, but it requires careful
Based on the 3 types of quality costs that have been discussed and reviewed above, I recommend that we look at doing more appraisals and inspections during the manufacturing process, this will limit the number of design changes that happen early in the process but it should help in cutting down our external failure costs and help limit
According to the data I collected, accuracy and precision do remain for the most part constant for the different volumes. I was the most accurate during one of my measurements of 200 µL, but I was the most precise with my measurements of 25 µL and 50 µL.
Weight 10 dry post-82 pennies which get 77.12g, using 30ml initial volume measuring the volume of 10 pennies, record the data 9.1ml. Using equation Density= Mass/Volume, get the density of the pre-82 pennies is 8.47g/ml. Then calculate the error%=0.04%, and the deviation%=7.13%.
Remove the spinning mass from the apparatus, measure and record the mass. The experimental uncertainty in m is determined by the scale’s uncertainty. Replace the spinning mass onto the apparatus, but do not attach the spring yet. Obtain a bulls-eye level and adjust the leveling screws to level the apparatus. Return the bulls-eye level.
2. The Impression in data: Larger the cell less is the error, smaller the cell more is the error.
The number of defective pieces that are received by customers can be a measurement of perfect orders. An error code can be developed for faulty power tools. The following percentages can also be used:
Fine tuning your writing is to help keep the writers writing focused on what it is they want to say. When writing a paper or anything people seem to think the only way to either get the point across or seem more educated is to use big fancy words. When a writer want’s others to understand them and believe them then their tone must accompany not only the audience but also what it is he or she is trying to say. Zinsser’s gives a perfect example of this when he talks about the 1960s letter that the principal of his university wrote to the alumni saying “You are probably aware that we have been experiencing very considerable potentially explosive expressions of dissatisfaction on issues only partially related” (Zinsser Professor, 1960). When reading
The optimal parameters that yield minimum surface roughness, minimum roundness error and maximum material removal rate are predicted based on genetic algorithm using MAT lab. The developed empirical models given as Equation 3, 4 and 5 are used as the fitness functions for determining the material removal rate, roundness and surface roughness value of each new individual. The optimization was run for a 1000 number of iterations with a population size of 100. The GA operators used in this search process are:
Therefore, a theoretical uncertainty value that accommodates both uncertainties of the measurement and the equipment is calculated. The theoretical uncertainty calculation is primarily based on the propagation of error formula. The theoretical uncertainty calculation is as follows.
The difference between Sipher, Zinesser and Dweck is very remarkable. Sipher is the type of guy who would give a person one chance to represent themselves and cast them out if he doesn't agree with their actions; instead of seeing where the problem is steaming from. Dweck is the total opposite she feels if a student is failing it's due to having a fixed and growth mindset. A fixed mind set is when a person isn't capable of accepting challenge and hates to be wrong, growth mindset is where the student likes a challenge, will to continue to try, they're very open minded and the solution to change the situation would come from the teacher those with growth mindset accelerate more than those with a fixed mindset it's like a card board box their
I think the purpose of Zitkala-Ša’s writing is to show how she felt experiencing a new place away from her family and experiencing a new culture. Zitkala-Ša’s village seems that it has its own traditions and culture. Zitkala-Ša’s did not know any of the white pale face cultures and it shocked her and surprised her. For example, when she first arrived and a rosy-cheeked paleface women caught her (carried her), Zitkala-Ša’s was “frightened and insulted by such trifling.” She wanted to be put down and to stand on her feet. Other children in today culture always like to be held and carried. However, the way she explained how her mother never made a playing of her wee daughter, shows us how her culture doesn't like to get close or physical with
A third disadvantage of applying JIC manufacturing operations is having lower quality assurance methods and even further, lower customer satisfaction (“Just-in-case and just-in-time…”). While the just-in-case system is beneficial in
In most cases, computer controlled machinery affixes components onto the casing using advanced adhesives. However, because of incompatibility issues between materials, the batteries and electric motors have to be bolted on to the casing by hand, using power tools. Operatives work on the line, each making an average of 12 bolts onto the casing, ie, 1 person bolts the battery and then someone further down the line bolts the electric motor. The inspection section for the back casing of the body is the most active, the rejection rate for loose components at this point is approximately 1.2 %. A further 0.5% are rejected at final inspection, causing expensive rework situations. There is a staff turnover of 25% per annum amongst such operatives in the back casing sub assembly section.
In small scale automobile part manufacturing company producing a large amount of products. A multiproduct manufacturing facility has the wide process which involves a large number of variables such as quality characteristics. Each and every product has been different quality characteristics which are measured on the manufacturing line. But when multiple products are produced or manufacturing trough a single processing line in multi product manufacturing facility, individual process monitoring strategies are used for monitoring the process of individual parts. So the challenge is that to develop a statistical process control charts for detection and implementation of faults using the quality characteristics.