Project

# Title Team Members TA Documents Sponsor
40 Precision Dumbbell Assistant
Cole Trautman
Ellie Beck
Ronit Kumar
Douglas Yu design_document1.pdf
final_paper1.pdf
presentation1.pptx
proposal1.pdf
proposal2.pdf
video
# Team Members
- Cole Trautman (colept2)
- Ronit Kumar (ronitk2)
- Ellie Beck (elliana2)

# Problem

Many gym goers struggle to maintain proper form during their workouts with dumbbells, which is why they rely heavily on exercise machines. However, if you are trying to construct an at-home gym, it is not feasible to order too many machines. Hence, there should be a way to help people maintain proper form even when they just use dumbbells. To start simple, we will first make our design compatible with bicep curls. We will add more exercises depending on time constraints.

# Solution

Our design will use 3 6-axis (accelerometer and gyroscope) IMU sensors on each arm to calculate the position of each arm and ensure that the user is performing the exercise correctly. There will be two small sensor boards located on the lower arm and shoulder, and a larger main board with another sensor on the upper arm. There will also be a battery that will be attached to the user, most likely on the upper arm or back. There will be a total of 5 subsystems in this design: sensing, processing, wireless communication, feedback, and power

# Solution Components

## Sensing

The sensing subsystem consists of 6 total LSM6DSMTR 6-axis IMUs, 3 for each arm. Each IMU will be on its own board, and connected to the processor via SPI. As mentioned before, the sensors will be located on the lower and upper arm, as well as the shoulder, which should allow us to accurately track the entire arm and dumbbell. The two small sensor boards will be connected to the main board with some kind of wire harness for power and SPI.

## Processing

The processing subsystem contains the two ESP32 processors. These were chosen because of their wireless capabilities, which we will get to later. Each processor will initialize its three sensors and then read in the sensor data and make sure that they are within the threshold necessary to perform the exercise correctly.

## Wireless Communication

This subsystem will handle the communication between the two ESP32 processors, as well as to the user’s phone so that they can see feedback via the feedback subsystem. We plan to use BLE (Bluetooth Low Energy), but if we run into problems with that ESP32 also should support WiFi.

## Feedback

This subsystem will handle the audible and visual feedback needed to let the user know whether they are doing the exercise correctly or not. We plan to have a buzzer on each main board to provide audible feedback, and a phone app to provide visual feedback. We want to at least list data regarding the number of curls, speed of workout, and angle of movements. Based on the data, it will compile a report that describes the accuracy of the user's form. If we can make some sort of graphic that displays where the movement was incorrect that would be incredibly helpful, although implementing this feature seems like it would be very time consuming.

## Power

Power will come from two 3.7V Li-ion battery packs, one on each arm. We plan to have these near the main board that attaches to the upper arm, but if it is too heavy it could be located elsewhere. This subsystem will also contain the circuitry needed to convert the voltage down to the voltage needed by the processor and sensors if needed.

# Criterion For Success

Our device needs to be accurate in motion and form analysis. To test this goal, we should be able to move our arms at the same distance and angle that we determine from our research of an online fitness expert and the feedback should be positive. We will also need to test each of our sensors individually to ensure that the accelerometer and gyroscope are providing accurate data based on our movements.

We also need to provide real time feedback to the user for improper form. To test this goal, we will purposely use improper form and the buzzer should sound to alert the user.

Our device should also allow the user to do proper movements. When we connect the sensors and ESP32 microcontroller, we will have to make sure that we don’t have overly rigid connections that prevent the user from moving their body parts naturally.

Electronic Automatic Transmission for Bicycle

Tianqi Liu, Ruijie Qi, Xingkai Zhou

Featured Project

Tianqi Liu(tliu51)

Ruijie Qi(rqi2)

Xingkai Zhou(xzhou40)

Sometimes bikers might not which gear is the optimal one to select. Bicycle changes gears by pulling or releasing a steel cable mechanically. We could potentially automate gear changing by hooking up a servo motor to the gear cable. We could calculate the optimal gear under current condition by using several sensors: two hall effect sensors, one sensing cadence from the paddle and the other one sensing the overall speed from the wheel, we could also use pressure sensors on the paddle to determine how hard the biker is paddling. With these sensors, it would be sufficient enough for use detect different terrains since the biker tend to go slower and pedal slower for uphill or go faster and pedal faster for downhill. With all these information from the sensors, we could definitely find out the optimal gear electronically. We plan to take care of the shifting of rear derailleur, if we have more time we may consider modifying the front as well.

Besides shifting automatically, we plan to add a manual mode to our project as well. With manual mode activated, the rider could override the automatic system and select the gear on its own.

We found out another group did electronic bicycle shifting in Spring 2016, but they didn't have a automatic function and didn't have the sensor set-up like ours. Commercially, both SRAM and SHIMANO have electronic shifting products, but these products integrate the servo motor inside the derailleurs, and they have a price tag over $1000. Only professionals or rich enthusiasts can have a hand on them. As our system could potentially serve as an add-on device to all bicycles with gears, it would be much cheaper.

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