| Experimental ergonomic evaluation with user trials: EEE product development procedures | ||
|---|---|---|
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The study consisted of six substudies, which can be divided according to the evaluated objects into more physical and more ICT-related as follows:
step experiment: outdoor stairs, steps to sauna benches, steps to a tractor cab (paper I)
task-surface experiment: task-surfaces of kitchen facilities and chairs (paper II)
chair experiment: multipurpose chairs (papers IV and V)
microwave oven experiment: microwave oven work stations (paper III)
telephone experiment: telephones (paper VI)
videophone experiment: videoconferencing system and telemedicine (paper VII)
Table 4 shows in more detail the objects evaluated with the different places where the evaluations were made and the relevant paper. At the beginning of this study, a static mock-up simulator was constructed at the University of Oulu. This “home simulator” was a room where the subjects could perform different tasks typical of the home environment. The room contained furniture and fixtures whose heights could be adjusted stepwise or with various task-surface heights (papers I and II). The testing facilities of the home simulator were later moved to Muhos and incorporated into the Finnish Laboratory of Applied Ergonomics (Soveltavan ergonomian laboratorio, SEL) in connection with the Päivärinne rehabilitation hospital. The evaluation of microwave oven work stations (paper III) and the prototypes of chairs (papers IV and V) were made in this laboratory. The telemedicine system (paper VII) was evaluated in an actual use context at a health care centre with real patients. The same procedure was also applied to the tractors and the farmers (paper I). The evaluation of telephones (paper VI) was done with real products by the elderly in a service and hobby centre and as schematic representations (concepts) of the telephones on paper by the researchers and nurses in a classroom.
Table 4. Targets to be evaluated in the papers and places of user trials.
| Object evaluated (a total of 3721 individual trials) | Place of trial | Paper |
|---|---|---|
| Access to 44 tractors with 6 mountings on each (264 individual mounting trials) | farm | Ia |
| 5 mountings by each subject: 3 sets of ordinary outdoor stairs and 2 sets of steps leading to sauna benches (240 individual mounting trials) | home simulator | Ib |
| 3 different work surfaces of a kitchen facility at 2 heights and 4 chairs (2 types of chairs at 3 heights) (550 individual trials) | home simulator | II |
| 4 real microwave oven work stations at 3 different heights were used to simulate the 10 arrangements described on conjoint cards (270 individual trials) | usability laboratory in SEL | III |
| 8 chair criteria presented by pictures for criterion weighting and 10 prototypes of chairs (1405 individual trials) | usability laboratory in SEL | IV |
| 8 chair criteria presented by pictures for criterion weighting and 3 prototypes of chairs (124 individual trials, 52 of them the same as in the paper III) | usability laboratory in SEL | V |
| 12 telephones of 4 different types (204 individual trials) | service and hobby centre for the elderly | VIa |
| 4 telephone concepts presented as illustrations (104 individual trials) | lecture hall | VIb & VIc |
| 4 physical evaluations of the system and 8 statements on telemedicine using a videoconferencing system (612 individual trials) | health care centre | VII |
In some substudies, the subject was given presentations of the products on paper (papers V, VIb, VIc) or both a paper and some real products to experiment with (paper III), or else all the products were actually evaluated (papers I, II, IV, VIa). This made the types concrete for the subjects. The products could be touched, handled, etc. Or there were just statements (VII) to be evaluated by the patients with experience of the situation.
In paper I, an expert objectively evaluated the interaction between the subject and the product. The expert measured the steps to a tractor and sauna benches and observed which foot the subjects used first when mounting the steps. In paper II, an expert (physiotherapist) rated the furniture heights according the subjects’ performance, and in paper VI, experts, who were geriatric nurses and gerontechnology researchers, ranked the telephones based on their experiences of the needs of the elderly. The data were gathered with a questionnaire in the videophone experiment (paper VII) and by the person conducting the experiment in the other instances.