Development and Evaluation of Anti-Vibration Toolkit for a Pneumatic Blueberry Handheld Harvester
Open Access
- Author:
- Kore, Rugved
- Graduate Program:
- Industrial Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- March 29, 2020
- Committee Members:
- Andris Freivalds, Thesis Advisor/Co-Advisor
Ling Rothrock, Program Head/Chair
Robert Carl Voigt, Committee Member
Ling Rothrock, Committee Member - Keywords:
- Ergonomics
Vibration
Reduction
Human Factors
Evaluation
dosimeter
AV
AV handle
AV gloves
Agriculture
Blueberry Harvester
Hand-arm
HAVS
Hand arm vibration syndrome - Abstract:
- Blueberry harvesting with handheld shakers is repetitive, exhausting and time-consuming work. Operators, who work without safety gloves, are more susceptible to various risks such as hand-arm vibration syndrome (HAVS) or work-related musculoskeletal disorders (WRMSDs). Unfortunately, despite many analyses were conducted on the potential threat of HAVS and WRMSDs from these handheld harvesters, there is still no solution has been suggested. Therefore, the goal of this dissertation is to develop and evaluate an anti-vibration (AV) handle and a pair of gloves in an AV kit in order to reduce the harmful vibrations of the shaker transferred to users’ arms and hands. Method –The AV kit included an AV handle and AV gloves. The chosen handle was picked out based on the least vibration transfer ratio among five different AV handles developed by trial – error method. The gloves were procured based on ISO 10819 complaint and previous researches. After the kit was fully developed, analyses on user discomfort and total reduction in vibration transfer began. Ten participants (M:5, F:5) were recruited from the university campus. -Dosimeter then was employed to record the vibration transfer to both users’ hands while using the machine in the following subsets: (1) Left hand (upper hand on the tool) without AV kit on either hand. (2) a left hand with an AV kit on both hands. (3) a left hand with AV handle and without AV gloves on both. (4) a right hand without AV gloves on both hands and no AV handle for left hand. (5) a right hand with AV gloves and AV kit for left hand. After every subtask, discomfort ratings for both hands and body parts were collected for posture analysis. The result- The average vibration exposure over the period of 8 hours – A (8) under the utilization of AV kit ranges between 4.94 to 9.07 m/s^2, while it was within the range of 14.32 – 17.33 m/s^2 without AV kit./. A total of 50% significant (p= 1.26-12) vibration reduction is achieved by the application of AV kit. However, the reduction is not enough to bring down the overall average vibration transferred below the ELV value of 5 m/s2 set by the European Directive (2002/44) to protect the user from HAVS. Body part discomfort score analysis concludes that posture required to operate the machine with the AV kit is more comfortable than the posture required to operate the machine without AV kit. According to ODR, pain, and numbness is reduced after utilizing the AV kit. Conclusion- The study confirms that the use of this AV kit reduces the harmful vibrations transferred to the user from the machine. Nevertheless, more research on the AV handle design and AV gloves needs to be done in order to bring down the vibration exposure below ELV. Along with that, the user body posture during machine operation also should be put into consideration as one of the important factors in handle the redesigning process.