31.05.2013 Views

Design of an ergonomic control lever for wheel loader attachments

Design of an ergonomic control lever for wheel loader attachments

Design of an ergonomic control lever for wheel loader attachments

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

6.2 Wheel <strong>loader</strong> operators <strong>an</strong>d task<br />

6.2.1 User Pr<strong>of</strong>ile <strong>of</strong> machine operators<br />

The purpose <strong>of</strong> the User Pr<strong>of</strong>ile (chapter 4.2.6) was to underst<strong>an</strong>d the operator’s<br />

perquisites <strong>an</strong>d to find user characteristics. To gather in<strong>for</strong>mation about the operators,<br />

semi-structured interviews (chapter 4.1.3) were made with a salesm<strong>an</strong> from Volvo CE’s<br />

dealer Swecon in Gothenburg, a repairm<strong>an</strong> <strong>an</strong>d previous machine operator at Vik<strong>an</strong>s<br />

Kross <strong>an</strong>d with machine operators from Per E Person Tr<strong>an</strong>sport AB in Borås, Stig<br />

Gustavsson Maskin AB in Borås <strong>an</strong>d Niclas Entreprenad AB in Torsl<strong>an</strong>da.<br />

Background<br />

The primary user <strong>of</strong> a <strong>wheel</strong> <strong>loader</strong> is the machine operator. The majority (98%) <strong>of</strong> the<br />

Swedish machine operators are men. However, the amount <strong>of</strong> female machine operators<br />

has been steadily increasing during the past years. The age <strong>of</strong> the machine operators vary<br />

from 20 years old to age <strong>of</strong> retirement, the majority <strong>of</strong> the operators are middle aged. At<br />

Vik<strong>an</strong>s Kross the machine operators are from 35 years old <strong>an</strong>d upward. A machine<br />

operator education is required to operate the machines. In order to apply <strong>for</strong> the<br />

education <strong>an</strong> elementary school degree <strong>an</strong>d a driver’s license <strong>of</strong> type B is needed<br />

(Arbetsförmedlingen, 2011).<br />

Usage<br />

The operators <strong>of</strong>ten work long hours. In Sweden the work hours are <strong>control</strong>led by<br />

federation <strong>of</strong> labor union to a maximum <strong>of</strong> 48 hours a week including overtime. (Seko,<br />

2011) A regular workday consists <strong>of</strong> 8 hours <strong>of</strong> work where the operator has a morning,<br />

lunch <strong>an</strong>d afternoon break. The operator <strong>of</strong>ten works 2-3 hours at a time in the<br />

machines.<br />

The operator needs to have good knowledge about the machine. The operators must<br />

probably read the instruction m<strong>an</strong>ual in order to use the full potential <strong>of</strong> the machine or<br />

at least per<strong>for</strong>m a trial <strong>an</strong>d error period. When operating the machine there is a close<br />

interaction between the operator, machine, task <strong>an</strong>d environment. An operator that uses<br />

the same machine c<strong>an</strong> have different attachment to the machine, which makes it<br />

import<strong>an</strong>t that he/she learns to use the machine in various ways. The operator has to<br />

learn how to operate the machine <strong>an</strong>d has to practice in order to become good at it. It<br />

c<strong>an</strong> take several years to learn how to find a good bal<strong>an</strong>ce between the functions <strong>of</strong> the<br />

machine, tasks <strong>an</strong>d different environments.<br />

For the employer it is import<strong>an</strong>t that the operator has experience. According to Billm<strong>an</strong> 3 ,<br />

a more experienced operator work more efficient <strong>an</strong>d economically. E.g. when <strong>an</strong><br />

experienced operator operates the machine they m<strong>an</strong>age to consume less fuel th<strong>an</strong> a new<br />

3 Gör<strong>an</strong> Hägg, Pr<strong>of</strong>essor, KTH, verbal contact (mail) 27 th <strong>of</strong> September 2011<br />

3 Ralf Rosenberg, <strong>Design</strong>er Msd,<br />

43

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!