electro-mechanical safety lift for self- spotting bench press machine proposing students: chris...
TRANSCRIPT
Electro-mechanical Safety Lift for Self-spotting Bench Press Machine
Proposing Students:Chris Potts (EE) & Lane Caffaro (ME)
Project Supervisors:Professor John Spinelli &Professor Jennifer Currey
Motivation
Everyone wants the perfect body New training programs, dietary supplements, and workout
machines
Maximize potential muscle growth Working muscles until failure
Dangerous without a spotter Work until lifter doubts he/she can lift the bar No human spotter Still augment muscle capacity with safety as a priority
Data Subjects
Inexperienced lifter (53 years old) Never lifts
Middle-aged male (41 years old) Lifts approximately (1 time per week)
Male students (both 22 years old) Lifts regularly (3-4 times per week)
Female students (18 & 20 years old) Lifts regularly (3-4 times per week)
Position
Female (18) – 95 lbs. (no fail)
Male (22) – 185 lbs. (failure)
Velocity
Female (18) – 95 lbs. (no fail)
Male (22) – 185 lbs. (failure)
Acceleration
Female (18) – 95 lbs. (no fail)
Male (22) – 185 lbs. (failure)
Parameters
Vertical range: 1.2 ft, 2 ft.
Horizontal range: TBD (≈ 6 inches)
Velocity range: ± 1 m/s
Acceleration range: ± 4 m/s2
Weight range: 65 lbs., 185 lbs.
Activation Options
Automatic Lifting when unnecessary
Foot pedal Inconvenience
Voice activated Too much interference
Manual switch on bar Obtrusive grip
Control matrix Ease of use Safety Lifting at proper time Ease of installment Ease of operation Unobtrusive Cost
Design Requirements
Wireless push switch Activates the system
Motors Move up at a rate of 1 m/s
Capable of lifting up to 300 lbs. Switch placed in the bar for comfortable grip Output device
Repetitions, minimums/maximums Maximum time to rack bar: 2 s Maximum time to stop downward motion of bar after
engagement: 0.5 s
Hydraulic Design
Hydraulic Design
Hydraulic Design
Block Diagram
Limitations
Assistance of hydraulics Ability to lift up to 300 lbs. at a velocity of 1 m/s
Placing the switch in the bar to avoid obtrusive grip
Only normal wide-grip bench is applicable
Goals
Phase 1: Activating the system
Phase 2: Lifting the bar safely
Phase 3: Racking the bar safely Output device
Timeline
Fall term: IEF proposal (week 3) Gather data
Position, velocity, acceleration (week 6)
Horizontal movement (week 9)
Angle of Bar (week 9) Finalize design (week 8) Design report (week 10) Order parts (week 10)
Winter break: Complete phase 1
Winter term: Complete phase 2 (week 2) Complete phase 3 (week 5) Working prototype (week 6)
Conclusion
Working prototype of a Self-Spotting Bench Press Machine
Even without a human spotter he/she can work muscles until failure
Safety is a priority
Questions