Fig. 1.

Fig. 2.

Fig. 3.

Fig. 4.
![Implementation scheme of experiment (3 input factors on 2 levels) [42]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f3415f8d1bec042eac83d9/j_ama-2025-0008_fig_004.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKBY2AOJTK%2F20251216%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251216T170210Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEJ%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaDGV1LWNlbnRyYWwtMSJIMEYCIQDpGWJy5nYmL6vQIHHt%2BcL%2F3OSMUmRuP2Jq%2F0ZR1%2FLQBwIhAMOCdMyV4r3yYa%2BF%2FudRVaQIR4fmJylEiwzwqN7lTdT5KrwFCGgQAhoMOTYzMTM0Mjg5OTQwIgz4VpTpHrGQ%2BRwhfVIqmQUmdJgnr7B%2F2TCxvDKqjEoGFRsgxmY1WO7B2uHZlmD80cdU17oWnLhWozEmhOcl3%2FA2q7bDkKBAuPcFO1a7dNHauScY2SzHlX0kIwGWBTyagWuMSXxWSKl7tuRn79BzKKKgACwrvnuaElPejVfsbXCLbokYmV3F5d6L7ZvYrBqtQi69XC21CoAlb8Y6i6%2FgGjbHb96ZBwCqvP7cOXSUTpBBNcWXDb3SBoKgMOvVGHUg3rSkHFBWbeUJWEqFQuQLNZGIPzAiqdGcNpaQoxwYfz5gf2hRAObi1TmBBQCJk0SxpwaFBWoacduWkTQZ5HNbLbV2Y7aFE3mDRSzYCiCfLMQh7Mgepw0nBxMmfE85hi32y%2BHl0YbHclUDfuc6cLW%2FYcTSrFNW5DY1zlMhrYkTdcHwhlV1hhIJTQNjAopybRxyhl8UYT%2FarnBEwsCeDtNSkjr%2BbyoA4Mb304CzPuGRdqK9emQVbV5UYjlPpV4HDHxB%2Feh%2FvM4JIZO4n8g6cp3NqtH4DmY0IW9MSRtklWQp1NGIx%2FvKjGOq7aOzqrJapYKvKLlD5e4RXY6v%2FiOPFbAdlTfn5%2FqC4BWLoxMGssJ9k0H38JHeskVYSwPhVqIo0EtaUeEaKSM06dRorQWA4zp9F2C8ovAo54ubZDzgUdOR0AQTvRjPzuFLiqLDfhn7QV8H0gLPqSM190VJgPIW5IZZPui4U7%2FBneLPSyQBM0j6QtUb8Mst%2FeYnWZLJMIdEPA%2Bv6au%2BzISiEhwEeyP69vVeq%2B5DRurxZDk6yvkPWt7OPS0VcMYYkMEE%2FBKpoOMCHV5smh95YG7YQar4J%2FuRfCRSBakAngbpy9rbUzTx0nincY30w2DOtdkRQ%2B6llm11f5dKO2lDvaYDR9zwsjDY3YXKBjqwAWriJvfX%2BElci0gwZQievDMAbkmHC4QI%2FqxewR1beknZpaCkRtCONkVDPkjy%2BT4qSFomaXZUpQZ4%2FUCmLMIxbgvXVx2C%2F8RvVqLErXggh0KomRU%2B0YjqHSFLW6f4wXhBudqG47DjGNdcJofTT2PytMHHltz%2Fhgs2cVWnTfkhMiVrxvUgXovn9cYHmefQfFeOjU7b7EZJzwNBhn624LDbKUNBrlDn2%2FKsMwkUHsc1t%2Flz&X-Amz-Signature=ddf62fca357480d4c29403165b7f63a837add0b26f7e34f0acb6462f93bfa784&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 5.

Fig. 6.

Fig. 7.

Fig. 8.

Fig. 9.

Fig. 10.

Fig. 11.

Test results – measured bristle thickness
| Test number | y1 | y2 | y3 | y4 | y5 | y6 | y7 | y8 | y9 | y10 | y11 | y12 | ȳ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.64 | 0.55 | 0.55 | 0.63 | 0.73 | 0.64 | 0.59 | 0.51 | 0.41 | 0.41 | 0.55 | 0.56 | 0.56 |
| 2 | 0.9 | 0.6 | 0.83 | 0.48 | 0.66 | 0.74 | 0.73 | 0.64 | 0.43 | 0.95 | 0.86 | 0.86 | 0.72 |
| 3 | 0.6 | 0.52 | 0.62 | 0.53 | 0.53 | 0.54 | 0.53 | 0.58 | 0.55 | 0.55 | 0.6 | 0.54 | 0.56 |
| 4 | 0.57 | 0.48 | 0.46 | 0.75 | 0.6 | 0.55 | 0.61 | 0.69 | 0.66 | 0.55 | 0.62 | 0.7 | 0.60 |
| 5 | 0.4 | 0.54 | 0.42 | 0.64 | 0.64 | 0.69 | 0.76 | 0.8 | 0.7 | 0.82 | 0.74 | 0.85 | 0.67 |
| 6 | 0.8 | 0.92 | 0.75 | 0.69 | 0.83 | 0.8 | 0.62 | 0.5 | 0.62 | 0.45 | 0.7 | 0.65 | 0.69 |
| 7 | 0.47 | 0.67 | 0.3 | 0.45 | 0.46 | 0.4 | 0.36 | 0.4 | 0.38 | 0.35 | 0.56 | 0.5 | 0.44 |
| 8 | 0.3 | 0.4 | 0.55 | 0.59 | 0.3 | 0.63 | 0.53 | 0.56 | 0.64 | 0.77 | 0.89 | 0.49 | 0.55 |
Test matrix, columns X1, X2, X3 define the top level (“+”) and bottom level (“−”) of selected process parameters
| Test number | X1 | X2 | X3 | Rotationai speed rpm | Engagement as brush diameter mm | Number of brushed parts |
|---|---|---|---|---|---|---|
| 1 | + | + | + | 2000 | 200 | 60 |
| 2 | + | + | − | 2000 | 200 | 30 |
| 3 | + | − | + | 2000 | 198 | 60 |
| 4 | + | − | − | 2000 | 198 | 30 |
| 5 | − | + | + | 1400 | 200 | 60 |
| 6 | − | + | − | 1400 | 200 | 30 |
| 7 | − | − | + | 1400 | 198 | 60 |
| 8 | − | − | − | 1400 | 198 | 30 |
Results of the tests - the radius of edge break in chosen locations of the detail
| Test number | Measured value of Edge break, mm | |||||
|---|---|---|---|---|---|---|
| - | A | B | C | D | E | F |
| 1 | 0.16 | 0.11 | 0.17 | 0.16 | 0.31 | 0.29 |
| 2 | 0.15 | 0.10 | 0.13 | 0.15 | 0.34 | 0.36 |
| 3 | 0.18 | 0.19 | 0.17 | 0.14 | 0.25 | 0.27 |
| 4 | 0.27 | 0.16 | 0.19 | 0.19 | 0.33 | 0.3 |
| 5 | 0.17 | 0.12 | 0.18 | 0.14 | 0.24 | 0.27 |
| 6 | 0.13 | 0.11 | 0.13 | 0.13 | 0.29 | 0.25 |
| 7 | 0.13 | 0.12 | 0.15 | 0.13 | 0.30 | 0.30 |
| 8 | 0.14 | 0.10 | 0.20 | 0.13 | 0.32 | 0.35 |
Error variance for individual trials
| Test number | S2 |
|---|---|
| 1 | 0.0079 |
| 2 | 0.0253 |
| 3 | 0.0010 |
| 4 | 0.0070 |
| 5 | 0.0200 |
| 6 | 0.0171 |
| 7 | 0.0094 |
| 8 | 0.0276 |