A S tudy on the Dev elopment of Ex c lus iv e S ens or for Dete cting the Hy draulic Cy linder S troke 2000 2
A bs tract 1 1 2 5 2.1 5 2.2 7 2.3 8 2.4 / 9 2.5 9 2.6 10 3 11 3.1 11 3.2 15 3.3 / 19 3.4 80C196KC 24 4 Prototype Configuration 26
4.1 LVDT 26 4.2 Configuration 27 4.3 30 4.4 31 5 32 5.1 32 5.2 35 5.3 37 6 39 41 A ppendix 43
A Study on the Development of Exclusive Sensor for Detecting the Hydraulic Cylinder Stroke Han Lee Department of Control & Instrumentation Engineering, Graduate School, Korea Maritime University Abstract In order to compris e a basic closed- loop control system for hydraulic systems it is necess ary to detect the pis ton rod s troke of hydraulic cylinder. T here are many conventional type s ensors w hich have been applied to detect the dis placement of cylinders. Several types of LVDT s and magnetic sens ors are representative illustrations of them. How ever, they cannot reveal the original performance normally or they cannot be applied at all w here the operating circums tance of cylinders is beyond specifications of sensors. Especially, for the purpose of detecting the s trokes of cylinders mounted on heavy equipments, a s pecial exclusive s ensor must be used. Becaus e the operating circumstances of heavy equipments are so s evere that general purpose sens ors cannot endure s uch circums tance as a shock and a residual vibration induced by rough w orks. - 1 -
In the conclusion, an exclusive sens or mus t be developed to detect the strokes of hydraulic cylinders of heavy equipments. In this thesis, an exclus ive method for detecting the piston rod s troke for heavy equipments is sugges ted, w hich adopts a remote detecting technique using optical sens ors and optical fibers. T o do this, firs t of all, a kind of s cale treatment of pis ton rod is required and it is also proposed here. An entire implementation procedure of the proposed exclusive sens or is explained concretely. A prototype of the sens or is resulted from the procedure. And then, s everal experiments using the prototype are ex ecuted for verifying the effectivenes s of the sug gested method and the poss ibility of the remote detection. Finally, the conclusion is demons trated bas ed on the experimental results. - 2 -
1..,.. N S... A/D.. - 1 -
housing. 1.1. (Heat source).., 1 (Bucket) (Residual vibration), housing [1]... ( ) Kayaba[1], [2],., housing. - 2 -
[3]., prototype.. 2 3. 4 prototype, 5 prototype. 6. - 3 -
1.1 T able 1.1 Performance comparison of sensors Operating Specs. Vibration T emp. Sens ors (G) ( ) Heavy Equipment - 40-100 25G above JC40S Potentio - meter L V D T Hall Sens or Encoder Resolver Shock Sensing Resolution Accuracy (G) Time 120G 1mm below above [COPAL - 40-100 15G 100G 0.05% (Japan)] LP- 100FP [MIDORI - 13-176 15G 50G 1% (Japan)] LP- 10FBS- 3 [MIDORI (Japan)] - 40-212 10G 50G 1% GYMT C- 11 less than [SANT EST - 5-60 6G 20G 0.01%FS (Japan)] 1kHz BT L- A [BALLUFF - 20-60 50G 12bit 2kHz (Germany)] AQLT [Data Instrument - 40-152 20G 50G 0.05% (America)] KSSC- 050 [Kayaba - 20-75 5G 90G 0.5mm (Japan)] T S5000 20-25,000 [T AMAGAWA - 10-75 10G 100G Pulses (Japan)] 200 sec A2- E2 [U.S Digital - 13-185 20G 100G 10000rpm (America)] CE- 65- S ISI (T R Electronic (Germany)] 0-60 10G 100G 6000rpm T S2013N94E23 7200 0.28% [T AMAGAWA - 30-100 15G 100G 30 msec Pulses for 180 (Japan)] - 4 -
2 2.1.., [3].,,,.. [4]. 2.1. (Piston rod part), (Fiber sensor part), / (Up/dow n counter part), - 5 -
(Data processing part), (Output part). 2.1 Figure 2.1 A basic configuration diagram of sensor for remote stroke detection - 6 -
2.2 2.2.1.,,... Hunger, Al2O3,. 2.2.2., - 7 -
.. 2.3 2.3.1,.. 2.3.2.,. 2 1 2., 1. - 8 -
2.3.3,,. 2.4 / 2 /. [5]. CPU. 2.5, /.,. CPU - 9 -
. 2.6., (Indicator) LCD (Bar). - 10 -
3 3.1.,..,. Fe++ Cl--. 3.1 Hunger 3.2. 3.1... Al2O3-11 -
......,. 3.1. - 12 -
3.1 Figure 3.1 A Process of scaling piston rod - 13 -
3.1 (Hunger ) Photo 3.1 Ceramic- coated hydraulic cylinder(hunger Co.) 3.2 (Hunger ) Photo 3.2 Process of ceramic coating on piston rod(hunger Co.) - 14 -
3.2 3.2.1,...... 1mm 0.5mm,.,. 1ms. - 15 -
3.2.1. NPN 2. 3.2 Figure 3.2 Amplifier circuit,. - 16 -
3.2.2 3.3 Figure 3.3 A setting method of optic fiber head. A B 90,. 1mm 0.5mm A B 90 /. 3.3 90. - 17 -
. 3.2.3. 3.4.. Output of chrome scale Output of ceramic scale 3.4 F igure 3.4 Output of optic fiber amplifier for chrome and ceramic scales,. - 18 -
3.3 / 2 90 A B /. 3.3.1 A, B A B. 0.5mm 2 90. 3.5 A. 3.5 A,B Figure 3.5 Shapes of A and B phase for stroke increasing direction - 19 -
3.6 B A B. 3.6 A,B Figure 3.6 Shapes of A and B phase for stroke decreasing direction A B /. - 20 -
3.3.2 1/ 4 / 3.7 A B 2mm 4 1/4 [5]. 1mm 0.5mm,. 3.7 1/4 Figure 3.7 Counting method of scales by 1/4 partition of one period - 21 -
3.3.3 / 3.8 / NEC PD4701. 4, CPU. 350ns 8 low high 12. 3.8 / PD4701 Figure 3.8 Block diagram of up/dow n counter PD4701-22 -
3.3.4 / 3.9 A B, 90 /. high low. 3.9 A B Figure 3.9 A phase and B phase signal outputted from optic fiber amplifiers - 23 -
3.4 80C196KC 3.4.1 80C196KC 3.10 80C196KC[6]. LCD... 3.10 80C196KC Figure 3.10 T he schematic diagram for data processing using 80C196KC - 24 -
3.4.2 3.11. 3.11 Figure 3.11 Flow chart of data processing - 25 -
4 Prototy pe Config uration 4.1 LVDT LVDT, S A N T E S T LV DT GYMT C- 11- A- 600-24S- D.. 3.1 SANT EST LVDT T able 3.1 Characteristics of SANT EST LVDT A rticles N onlinearity Res olution H y s teres is S am pling frequency Output s ig nal (v oltag e) Output s ig nal (current) S upply voltag e Operating T em p. V ibration S hock S pecifications 0.05% below 0.01% below 0.01% below 1kH z s tandard 0-10V or 10-0V 4-20m A or 20-4m A +15V 5% P robe - 5 +60 / Controller 0 +60 6G M ax 20G M a x - 26 -
4.2 Config uration 4.1 prototype, 4.1 prototype.,,,, /,., SANT EST LVDT. - 27 -
4.1 prototype Figure 4.1 Configuration diagram of a prototype developed in this thesis - 28 -
Piston rod Optic fiber head LVDT Am p LVDT Controller Data processing board 4.1 prototype Photo 4.1 Developed prototype for remote detection of stroke - 29 -
4.3 4.2 1mm, / 2 90. Optic Fiber head Scaled piston rod 4.2 Photo 4.2 Real setting betw een scaled piston rod and optic fiber head - 30 -
4.4 4.3 80C196KC, LVDT. LCD LVDT 10. LVDT Controller LCD Display Optic fiber A mp. Data Processing Board 4.3 80C196KC Photo 4.3 Data processing board using 80C196KC - 31 -
5,.. LVDT. 5.1 5.1 LVDT. 5.1. 0.5mm 0.5mm,. - 32 -
(a) In case of increasing the stroke - 33 -
(b) In case of decreasing the stroke 5.1 LVDT Figure 5.1 Output comparison of the stroke sensor w ith LVDT - 34 -
5.2.. 5.2 LVDT. LVDT AD LVDT.. (a) In case of increasing the stroke - 35 -
(b) In case of decreasing the stroke 5.2 LVDT Figure 5.2 Relation betw een the stroke sensor and LVDT for verifying the linearity - 36 -
5.3.. 5.3 (a) LVDT. 5.3 (b) LVDT. 0.2mm. 0.5mm LV DT A D LVDT. (a) (b).. - 37 -
(a) Output of the stroke sensor w ith LVDT for verifying the bidirectional repeatability (b) Error of stroke sensor and LVDT 5.3 Figure 5.3 Output comparison of the stroke sensor w ith LVDT for verifying the bidirectional repeatability - 38 -
6., prototype.,...,, 1mm 0.5mm. prototype, - 39 -
... - 40 -
[1],,, ( ), 1992. [2] S. Y. Yang, M. C. Lee, M. H. Lee, "Measuring Sys tem for Development of Stroke- Sensing Cylinder for Automatic Ex cavator," IEEE T rans on Industrial Electronics, vol. 45, no. 3, pp. 379-384, June 1998. [3],, no. 4,, pp. 30-36, 1989. [4], FA 2,, PP. 36-53, 1995. [5],, no. 3 P A R T -,, pp. 16-21, 1989. [6], M ICR O CON T R OLLE R 80196,, 1997. [7],,,, 10, pp.61-76, 1992. [8] S. Y. Yang, M. C. Lee, M. H. Lee, and S. Arimoto, "Development of digital stroke s ensing cylinder and its performance evaluation," Robotica, vol. 14, pt. 6, pp. 687-694, 1996. - 41 -
[9] M. C. Lee, M. H. Lee, Y. J. Choi, S. Y. Yang and K. S. Yoon, "On Development of Stroke Sensing Cylinder for Automatic Excavator," Proc. of the IEEE ISIE ' 95, vol. 1 of 2, pp. 363-368, 1995. [10],,,, 98, pp. 329-333, 1998. - 42 -
Appendix prototy pe A.1 80C196KC - 43 -
A.2 A/ D - 44 -
.,,., 2,,,,,.,,..,. - 45 -