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 / s 2  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

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