b928f4b529a9f135c59f05e1f82ae89c.ppt
- Количество слайдов: 28
Team K-TRON Team Members: Ryan Vroom Geoff Cunningham Trevor Mc. Clenathan Brendan Tighe
Outline • Project definition • Overview of design process > Important decisions made with rationale • Concept selection > Concept chosen with validation • Implementation plan • Final remarks
SFTII Project Scope » Design a testing apparatus to produce external vibration to the SFTII load cell under specific loading Metrics: • Apply mass of 120 kg in 6 increments • Frequency range: Achieve 120 Hz (112 Hz “magic number”) and as low as possible • Acceleration range: 0. 05 g – 0. 3 g • Max displacement of 1 mm
Adding Value to Sponsor’s Business • Exact modeling can increase load cell accuracy -Filtering out environmental noise • Allow K-TRON to remain as the “World’s number one feeder company”
Subsystem Design Load Cell Testing Apparatus Actuator Upper Frequency Range >112 Hz/ Achieve Range of G Forces/Repeatable Application of Mass 0 -120 kg Frame Design Include Flexures/ Adaptable to both Load Cells
Benchmarking: Actuator Bose Electro-Magnetic Linear Drive: • Cost: ~ $35, 000. 00! • Production time ~ 3 years Parker Linear Actuator: • Can only work up to 100 Hz • Requires load relieving • Expensive: Actuator/Controller combo costs ~$11, 000. 00
Benchmarking: Actuator BEI Kimco Voice-Coil Linear Actuator: • Max load of 13. 5 kg Piezomechanik Piezoelectric Actuator: • Will need a very powerful controller (1000 V output) to work • Actuator/Controller combo= $13, 880
Benchmarking: Chosen Actuator • After checking calculations, determined lower voltage actuator could be used d=amplitude a=gravitational force Results Determined: » Low end frequency at low g force – 27 Hz at 0. 05 g’s » Low end frequency at high g force – 68 Hz at 0. 3 g’s
Benchmarking: Chosen Actuator Piezomechanik Piezoelectric Actuator, PSt 150/7/40 VS 12: • Lower voltage requirement 150 volts • 40 µm displacement • Max. load of 1000 N must use 100 kg instead of 120 kg • Actuator: $699. 00 • Controller: + $4990. 00 $5689. 00
Actuator: Cost Analysis Actuator Cost Analysis Concept Description Cost 1 Electro-Magnetic Linear Drive $35, 000 2 Parker Linear Actuator $11, 000 3 BEI Kimco Voice-Coil $900 4 Piezomechanik Piezoelectric System (1000 V) $13, 880 5 Piezomechanik Piezoelectric System (150 V) $5, 689
Benchmarking: Load Application Machined steel: • Cost of material greater than $115 per 20 kg mass • High machining time Machined lead: • Toxic issues • Cost of material greater than $140 per 20 kg mass • High machining time 45 lb weights: • High resultant moment
Benchmarking: Chosen Loading Application 25 lb. cast plates: • Small, circular shape reduces unwanted moment forces during testing • Pre-bored center hole reduces machining time • Low cost of $13. 99 per 11. 3 kg
Benchmarking: Chosen Loading Application • Weight selection determined center rod: – 1. 25 in. acme threaded rod-rod diameter ideal for existing hole and cost – Acme threaded collar to minimize movement of weights during testing – Analysis of rod under worst case scenario, assume cantilevered beam w/ distributed load » Safety factor of 5. 7 • Center hole diameter of weights, 2 -1/32 in. – Machine aluminum inserts that are press-fitted - provide slip fit between rod and plate
Loading Design: Cost Analysis Mass Loading Parts: # Description Cost Ea. ($) Cost ($) 12 25 lb. weight 13. 99 167. 88 1 Acme Threaded Collar 19. 78 1 3 ft. Acme Threaded Rod 40. 43 12 Weight Inserts 0 (scrap) 0 Total Cost ($) 228. 09 Machining: Time (hrs. ) Cost per hour Cost ($) ~20 free 0 Overall Cost excluding shipping ($) 228. 09
Exploded System Design 1) Base Plate 2) Steel Supports 3) Steel Struts 4) Support Blocks 5) Flexure 6) Flexure Connector 7) Weight Post 8) Rod Connecting screw 9) Load Cell 10) Actuator Connecting Screw 11) Actuator 12) Actuator Stabilizer 6 5 4 4 7 8 9 12 3 11 10 1 2
Completed System Design
Frame Design: Steel Support Tubing Main structural parts made of 1008 steel • 24” x 1” base plate • 1” x 1” square tubing • Support blocks Support block Square tubing – All steel parts welded to increase rigidity 1008 steel properties: • Elastic Modulus ~ 29, 000 ksi • Tensile strength ~ 49. 3 ksi • Yield Strength ~ 41. 3 ksi Base plate
Frame Design: Finite Element Analysis • Steel square tube with 80 N shear load at tip • Maximum deformation of 9. 42 e-4 in. • Factor of Safety > 9. 6
Frame Design: Flexures connect threaded rod to steel supports • Reduces lateral motion of the rod • All applied stresses are tensile
Frame Design: Finite Element Analysis • Stainless steel flexure device with 45 N tensile load applied at right cutout • Maximum deformation of 4. 26 e -3 in. • Factor of Safety > 8. 7
Frame Design: Actuator Support After speaking with Dr. Sun on possible failure: • Actuator support will be bolted to base plate using the four pre-existing screw holes • The support will keep Actuator from buckling under high loads Actuator support Actuator
Frame Design: Load Cell/Actuator Connector • Steel bolt body with 1000 N compression load applied at center gives factor of safety > 4. 17 • Effective loading difference on face is 471 N • Maximum deformation of 1. 5 e -5 in.
Frame Design: Cost Analysis Frame System Cost Analysis Parts: # Description Cost Ea. ($) Cost ($) 1 Steel Plate 421. 63 1 Steel Square Tube 19. 43 2 Flexures 0 (in house) 0 1 Alum. 6” x 6” Block 0 (scrap) 0 1 Alum. Flexure Connector 0 (scrap) 0 5 M 8 Bolts 0 (in house) 0 8 M 4 Bolts 0 (in house) 0 Total Cost ($) 441. 06 Time (hrs. ) Cost per hour Cost ($) ~20 free 0 Machining:
Overall Cost Analysis Mass Loading Cost All Supplies $228. 09 Frame System Cost All Supplies $441. 06 Actuator System Cost All Supplies $5, 689. 00 Total System Cost $6, 358. 15
Implementation Plan • Test the as-built apparatus to complete validation of design (in process) • Manufacture SFTIII adaptation mount • We will hand-off the project to KTron so they can test their load cells
Acknowledgements • Thank you to our sponsor at K-Tron: – Tim Baer – Jim Foley • Thanks to our advisor: – Dr. Keefe • Special thanks to: – Steve Beard
Exploded View Questions
Frame Design: Finite Element Analysis • Steel SFTIII adapter support with 720 N applied load at attached face • Maximum deformation of 2. 447 e-4 in. • Factor of Safety > 100 with full load (1600 N) applied
b928f4b529a9f135c59f05e1f82ae89c.ppt