Author Contributions
Conceptualization, X.S., H.L. and X.Q.; Methodology, X.S.; Software, X.S.; Validation, X.S.; Formal Analysis, X.S.; Investigation, X.S. and H.L.; Resources, X.S.; Data Curation, X.S.; Writing—Original Draft Preparation, X.S.; Writing—Review and Editing, X.S., H.L., X.Q., S.M.N., J.Y., Y.M. and J.W.; Supervision, H.L., X.Q. and J.W.; Funding Acquisition, H.L. All authors have read and agreed to the published version of the manuscript.
Figure 1.
The experiment bench schematic diagram. 1. Vacuum tube, 2. Fan, 3. The metering device, 4. Variable frequency motor, 5. Positive pressure tube, 6. Motor governor, 7. Conveyor belt, 8. Conveyor belt frequency modulator.
Figure 1.
The experiment bench schematic diagram. 1. Vacuum tube, 2. Fan, 3. The metering device, 4. Variable frequency motor, 5. Positive pressure tube, 6. Motor governor, 7. Conveyor belt, 8. Conveyor belt frequency modulator.
Figure 2.
Structural diagram of the metering device: (a) Front view; (b) Lateral view. 1. Seed box, 2. Outer seed-cleaning device, 3. Retaining tray, 4. Seed stirring wheel, 5. Front housing, 6. Inner seed-cleaning device, 7. Metering tray, 8. Diversion channel, 9. Diversion tube, 10. Sprocket wheel, 11. Vacuum pressure outlet, 12. Rear housing.
Figure 2.
Structural diagram of the metering device: (a) Front view; (b) Lateral view. 1. Seed box, 2. Outer seed-cleaning device, 3. Retaining tray, 4. Seed stirring wheel, 5. Front housing, 6. Inner seed-cleaning device, 7. Metering tray, 8. Diversion channel, 9. Diversion tube, 10. Sprocket wheel, 11. Vacuum pressure outlet, 12. Rear housing.
Figure 3.
The sucking hole structural diagram. (a) Sucking hole of the inner ring; (b) Sucking hole of the middle ring; (c) Sucking hole of the outer ring.
Figure 3.
The sucking hole structural diagram. (a) Sucking hole of the inner ring; (b) Sucking hole of the middle ring; (c) Sucking hole of the outer ring.
Figure 4.
Test materials and seeding performance test bench. (a) Brassica chinensis seeds; (b) Test bench. 1. Vacuum tube; 2. Variable frequency motor; 3. Metering device; 4. U-Manometer; 5. Motor governor; 6. Conveyor belt; 7. Positive pressure tube; 8. Conveyor belt frequency modulator; 9. Wind pressure detection system; 10. Fan frequency regulator; 11. Fan.
Figure 4.
Test materials and seeding performance test bench. (a) Brassica chinensis seeds; (b) Test bench. 1. Vacuum tube; 2. Variable frequency motor; 3. Metering device; 4. U-Manometer; 5. Motor governor; 6. Conveyor belt; 7. Positive pressure tube; 8. Conveyor belt frequency modulator; 9. Wind pressure detection system; 10. Fan frequency regulator; 11. Fan.
Figure 5.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the inner ring qualified index.
Figure 5.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the inner ring qualified index.
Figure 6.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the inner ring missed seeding index.
Figure 6.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the inner ring missed seeding index.
Figure 7.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the middle ring qualified index.
Figure 7.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the middle ring qualified index.
Figure 8.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the middle ring missed seeding index.
Figure 8.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the middle ring missed seeding index.
Figure 9.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the outer ring qualified index.
Figure 9.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the outer ring qualified index.
Figure 10.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the outer ring missed seeding index.
Figure 10.
Effect of (a) angular velocity of metering tray and vacuum pressure, (b) taper angle of sucking hole and vacuum pressure, and (c) taper angle of sucking hole and angular velocity of metering tray on the outer ring missed seeding index.
Figure 11.
Parameter optimization zone.
Figure 11.
Parameter optimization zone.
Table 1.
Measured dimensions of Brassica chinensis seeds.
Table 1.
Measured dimensions of Brassica chinensis seeds.
Parameter | Range | Mean | Standard Error |
---|
Length (mm) | 1.37–2.08 | 1.77 | 0.15 |
Width (mm) | 1.33–1.91 | 1.68 | 0.13 |
Thickness (mm) | 1.32–1.98 | 1.66 | 0.16 |
Thousand seed mass (g) | 2.39–2.43 | 2.41 | 0.013 |
Table 2.
Levels of experimental factors.
Table 2.
Levels of experimental factors.
Level | Factor |
---|
X1/kPa | X2/rpm | X3/° |
---|
−1 | 0.5 | 10 | 45 |
0 | 2 | 25 | 60 |
1 | 3.5 | 40 | 75 |
Table 3.
Test results.
NO. | Experimental Factors | Results |
---|
X1 | X2 | X3 | Y1/% | Y2/% | Y3/% | Y4/% | Y5/% | Y6/% |
---|
1 | −1 | −1 | 0 | 82.88 | 13.21 | 84.02 | 13.12 | 83.33 | 13.31 |
2 | 1 | −1 | 0 | 83.21 | 4.86 | 90.56 | 4.13 | 89.98 | 3.96 |
3 | −1 | 1 | 0 | 83.56 | 5.56 | 86.32 | 2.84 | 86.68 | 2.68 |
4 | 1 | 1 | 0 | 86.65 | 2.26 | 83.37 | 3.36 | 82.84 | 3.42 |
5 | −1 | 0 | −1 | 85.12 | 3.56 | 98.64 | 0.37 | 98.43 | 0.41 |
6 | 1 | 0 | −1 | 82.45 | 2.68 | 85.46 | 4.33 | 87.41 | 4.56 |
7 | −1 | 0 | 1 | 83.45 | 12.89 | 98.13 | 0.82 | 98.11 | 0.75 |
8 | 1 | 0 | 1 | 90.32 | 4.24 | 98.73 | 0.94 | 98.25 | 1.03 |
9 | 0 | −1 | −1 | 92.85 | 4.98 | 83.32 | 5.68 | 83.45 | 5.43 |
10 | 0 | 1 | −1 | 91.21 | 2.12 | 97.96 | 0.35 | 98.14 | 0.29 |
11 | 0 | −1 | 1 | 89.12 | 10.12 | 92.56 | 5.11 | 93.01 | 5.36 |
12 | 0 | 1 | 1 | 96.12 | 3.12 | 84.12 | 3.89 | 84.33 | 3.95 |
13 | 0 | 0 | 0 | 98.25 | 0.46 | 82.56 | 12.65 | 82.69 | 12.35 |
14 | 0 | 0 | 0 | 98.46 | 0.82 | 88.91 | 12.43 | 89.46 | 12.37 |
15 | 0 | 0 | 0 | 97.38 | 1.2 | 95.82 | 3.53 | 96.38 | 3.61 |
16 | 0 | 0 | 0 | 98.25 | 0.24 | 90.68 | 2.63 | 91.46 | 2.57 |
17 | 0 | 0 | 0 | 98.12 | 0.21 | 97.45 | 0.51 | 96.69 | 0.48 |
Table 4.
Variance Analysis result of inner ring seed-metering performance test.
Table 4.
Variance Analysis result of inner ring seed-metering performance test.
Performance Index | Source | Sum of Square | df | Mean Square | F Value | p Value |
---|
inner ring qualified index | Model | 641.89 | 9 | 71.32 | 121.43 | <0.0001 ** |
X1 | 7.26 | 1 | 7.26 | 12.36 | 0.0098 ** |
X2 | 11.23 | 1 | 11.23 | 19.13 | 0.0033 ** |
X3 | 6.81 | 1 | 6.81 | 11.59 | 0.0114 * |
X1X2 | 1.90 | 1 | 1.90 | 3.24 | 0.1148 |
X1X3 | 22.75 | 1 | 22.75 | 38.74 | 0.0004 ** |
X2X3 | 18.66 | 1 | 18.66 | 31.77 | 0.0008 ** |
X12 | 464.52 | 1 | 464.52 | 790.89 | <0.0001 ** |
X22 | 51.98 | 1 | 51.98 | 88.50 | <0.0001 ** |
X32 | 21.38 | 1 | 21.38 | 36.41 | 0.0005 ** |
Residual | 4.11 | 7 | 0.5873 | | |
Lack of fit | 3.42 | 3 | 1.14 | 6.58 | 0.0502 |
Pure Error | 0.6931 | 4 | 0.1733 | | |
Cor Total | 646.01 | 16 | | | |
inner ring missed seeding index | Model | 268.44 | 9 | 29.83 | 50.80 | <0.0001 ** |
X1 | 56.07 | 1 | 56.07 | 95.51 | <0.0001 ** |
X2 | 50.55 | 1 | 50.55 | 86.10 | <0.0001 ** |
X3 | 36.25 | 1 | 36.25 | 61.75 | 0.0001 ** |
X1X2 | 6.38 | 1 | 6.38 | 10.86 | 0.0132 * |
X1X3 | 15.09 | 1 | 15.09 | 25.71 | 0.0014 ** |
X2X3 | 4.28 | 1 | 4.28 | 7.30 | 0.0306 * |
X12 | 46.47 | 1 | 46.47 | 79.14 | <0.0001 ** |
X22 | 27.69 | 1 | 27.69 | 47.16 | 0.0002 ** |
X32 | 15.76 | 1 | 15.76 | 26.84 | 0.0013 ** |
Residual | 4.11 | 7 | 0.5871 | | |
Lack of fit | 3.40 | 3 | 1.13 | 6.40 | 0.0524 |
Pure Error | 0.7087 | 4 | 0.1772 | | |
Cor Total | 272.55 | 16 | | | |
Table 5.
Variance Analysis result of middle ring seed-metering performance test.
Table 5.
Variance Analysis result of middle ring seed-metering performance test.
Performance Index | Source | Sum of Square | df | Mean Square | F Value | p Value |
---|
Middle ring qualified index | Model | 618.60 | 9 | 68.73 | 131.05 | <0.0001 ** |
X1 | 6.86 | 1 | 6.86 | 13.09 | 0.0085 ** |
X2 | 11.50 | 1 | 11.50 | 21.92 | 0.0023 ** |
X3 | 6.55 | 1 | 6.55 | 12.49 | 0.0095 ** |
X1X2 | 0.5184 | 1 | 0.5184 | 0.9884 | 0.3533 |
X1X3 | 18.62 | 1 | 18.62 | 35.50 | 0.0006 ** |
X2X3 | 19.32 | 1 | 19.32 | 36.83 | 0.0005 ** |
X12 | 431.30 | 1 | 431.30 | 822.32 | <0.0001 ** |
X22 | 66.73 | 1 | 66.73 | 127.23 | <0.0001 ** |
X32 | 20.54 | 1 | 20.54 | 39.16 | 0.0004 ** |
Residual | 3.67 | 7 | 0.5245 | | |
Lack of fit | 2.57 | 3 | 0.8579 | 3.13 | 0.1499 |
Pure Error | 1.10 | 4 | 0.2745 | | |
Cor Total | 622.27 | 16 | | | |
Middle ring missed seeding index | Model | 289.83 | 9 | 32.20 | 228.06 | <0.0001 ** |
X1 | 40.41 | 1 | 40.41 | 286.18 | <0.0001 ** |
X2 | 66.01 | 1 | 66.01 | 467.48 | <0.0001 ** |
X3 | 39.52 | 1 | 39.52 | 279.85 | <0.0001 ** |
X1X2 | 8.76 | 1 | 8.76 | 62.05 | 0.0001 ** |
X1X3 | 16.08 | 1 | 16.08 | 113.88 | <0.0001 ** |
X2X3 | 10.30 | 1 | 10.30 | 72.97 | <0.0001 ** |
X12 | 37.60 | 1 | 37.60 | 266.31 | <0.0001 ** |
X22 | 30.21 | 1 | 30.21 | 213.93 | <0.0001 ** |
X32 | 29.53 | 1 | 29.53 | 209.16 | <0.0001 ** |
Residual | 0.9884 | 7 | 0.1412 | | |
Lack of fit | 0.7009 | 3 | 0.2336 | 3.25 | 0.1423 |
Pure Error | 0.2875 | 4 | 0.0719 | | |
Cor Total | 290.82 | 16 | | | |
Table 6.
Variance Analysis result of outer ring seed-metering performance test.
Table 6.
Variance Analysis result of outer ring seed-metering performance test.
Performance Index | Source | Sum of Square | df | Mean Square | F Value | p Value |
---|
Outer ring qualified index | Model | 600.93 | 9 | 66.77 | 187.92 | <0.0001 ** |
X1 | 3.37 | 1 | 3.37 | 9.48 | 0.0179 * |
X2 | 13.11 | 1 | 13.11 | 36.89 | 0.0005 ** |
X3 | 2.45 | 1 | 2.45 | 6.90 | 0.0340 * |
X1X2 | 0.6320 | 1 | 0.6320 | 1.78 | 0.2241 |
X1X3 | 31.47 | 1 | 31.47 | 88.58 | <0.0001 ** |
X2X3 | 17.94 | 1 | 17.94 | 50.48 | 0.0002 ** |
X12 | 434.81 | 1 | 434.81 | 1223.72 | <0.0001 ** |
X22 | 50.83 | 1 | 50.83 | 143.06 | <0.0001 ** |
X32 | 14.76 | 1 | 14.76 | 41.53 | 0.0004 ** |
Residual | 2.49 | 7 | 0.3553 | | |
Lack of fit | 0.5209 | 3 | 0.1736 | 0.3532 | 0.7905 |
Pure Error | 1.97 | 4 | 0.4916 | | |
Cor Total | 603.42 | 16 | | | |
Outer ring missed seeding index | Model | 287.86 | 9 | 31.98 | 182.45 | <0.0001 ** |
X1 | 43.62 | 1 | 43.62 | 248.81 | <0.0001 ** |
X2 | 64.41 | 1 | 64.41 | 367.43 | <0.0001 ** |
X3 | 37.58 | 1 | 37.58 | 214.40 | <0.0001 ** |
X1X2 | 7.98 | 1 | 7.98 | 45.52 | 0.0003 ** |
X1X3 | 16.85 | 1 | 16.85 | 96.12 | <0.0001 ** |
X2X3 | 8.91 | 1 | 8.91 | 50.83 | 0.0002 ** |
X12 | 35.97 | 1 | 35.97 | 205.18 | <0.0001 ** |
X22 | 28.20 | 1 | 28.20 | 160.84 | <0.0001 ** |
X32 | 32.96 | 1 | 32.96 | 188.00 | <0.0001 ** |
Residual | 1.23 | 7 | 0.1753 | | |
Lack of fit | 0.8735 | 3 | 0.2912 | 3.29 | 0.1399 |
Pure Error | 0.3537 | 4 | 0.0884 | | |
Cor Total | 289.09 | 16 | | | |
Table 7.
Comparison of the optimized value and actual value.
Table 7.
Comparison of the optimized value and actual value.
Type | Position | Optimized Value | Actual Value |
---|
Qualified index/% | Inner ring | 95.12 | 95.05 |
Middle ring | 94.68 | 93.98 |
Outer ring | 94.24 | 92.73 |
Missed seeding index/% | Inner ring | 3.67 | 4.12 |
Middle ring | 3.12 | 3.56 |
Outer ring | 2.58 | 2.86 |