Senior Project

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Senior Project Electrical Engineering
2009THE WINGMAN SELF-SPOTTING BENCH PRESSChris
Potts (EE) Lane Caffaro (ME)Advisors John
Spinelli (EE) Jennifer Currey (ME)
ABSTRACT In modern day society, health and
fitness have become the focus of many Americans.
As a result, working out and weight lifting plays
a large role in many peoples lives. In order to
obtain more strength, one must maximize his/her
potential muscle growth. The ideal way to do this
is by working the muscles until failure. This can
be extremely hazardous on the bench press machine
without a human spotter there to provide aid if
the circumstances require it. The Wingman allows
weight lifters to work their muscles until he/she
doubts him/herself capable of lifting the
barbell. A human spotter will become obsolete,
and the lifter will still be able to augment
his/her muscle capacity with safety as a
priority. The Wingman, there to take the fall so
you can be the strongest of them all.
DESIGN GOALS First, the system must meet the
definition of a free weight workout machine. This
means that the barbell must not have any
constraints on its directional motion and there
must be no outside contact with the barbell aside
from the weight plates and the lifters grip.
Also, the lifter must be able to comfortably grip
the barbell, so any switches for manual
activation must be unobtrusive. Second, the
system must act as a spotter and provide
assistance to the lifter only when it is
necessary. Therefore, the system must be able to
recognize when the lifter can no longer lift the
barbell, whether it be from manual activation by
the lifter or automatic activation by the system.
Third, the system must be able to lift the
barbell and weight vertically away from the
lifter in a relatively quick manner. Finally, it
would also be advantageous for the design to
include an output device that can display the
total time and the number of repetitions for each
set.
BLOCK DIAGRAM
SYSTEM DESIGN
EVALUATION The microcontroller was able to
properly communicate with all the switches,
sensors, and solenoid in order to raise/lower the
air pressurized pneumatic cylinders only when the
lifter needed assistance. The micro switches
correctly activated the system by energizing the
solenoid and deactivated the system once the
barbell was racked. The ribbon switches worked as
a manual trigger so as to deenergize the solenoid
when lifter released his/her grip. The distance
sensors automatically deenergized solenoid,
regardless of ribbon switch operation, if the
barbell was uneven by 6 or more inches or if
barbell was stationary for 2 or more seconds.
Lastly, the LCD accurately displayed the total
time and the number of repetitions for each set.
Therefore, the Wingman is a true free weight
system and a safe alternative to lifting without
a human spotter.
FLOW CHART
CIRCUIT DIAGRAMS Micro/Ribbon Switches
Solenoid Interface

• FUTURE Work - Wireless
• Regulator for Amount of Weight
• Sensors for Horizontal Movement
• Ready Beep/System Failure Alarm
• Attachment of Distance Sensors on Barbell
• Adjustable Range of Motion by Pneumatic Cylinders

NOTE For mechanical details, please see Lane
Caffaros poster in the ME wing.