Project Title Goes Here

Project team member(s): Allison Sample

Give a one-paragraph description/summary of the project, which includes information like the motivation for the project, the goals of the project, and the resulting implementation and success of the project.

Introduction

Explain the motivation for your project in terms of the educational objectives and why your haptic device is an appropriate approach.

Background

Explain the relevant prior work in the field of haptics and provide references. These will likely be different from the references in your project proposal. Make sure to do a thorough literature search on relevant haptic devices/application.

Methods

Provide a detailed description of your project, such that another student from the class could generally re-create your project/experiment from the report if necessary. (You don't need to document every screw, but the design should be clear.) Add images and videos as needed to support the description. You can refer to downloadable drawings and code in the "Files" section (later). You should divide this section into subsections, which can vary depending on your particular project. Here is an example set of subsections:

Hardware Design and Implementation

System Analysis and Control

Demonstration / Application

Results

Describe the results, which may include qualitative responses from users at the open house.

Future Work

Describe how your system could be tested (e.g., through experiments if you have not already done so), how it can be improved, and how it might be applied.

Acknowledgments

Here you can list any individuals or groups who helped you with your project. (e.g., another student in the class, a course assistant, or an especially helpful PRL TA). Optional, so delete this section if you aren't using it.

Files

Code and drawings should be linked here. You should be able to upload these using the Attach command. If you aren't willing to share these data on a public site, please discuss with the instructor. Also, in this section include a link to a file with a list of major components and their approximate costs.

References

List the referenced literature, websites, etc. here.

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Appendix: Project Checkpoints

Checkpoint 1

Our original Checkpoint 1 goals were to record drum sounds and vibrations, test whether those vibrations were distinct enough using small vibration modules, and test the force sensors to see if they could capture the input from being struck under the foam padding. These goals were meant to validate the basic signal chain of HaptiDrum before committing to the full vest and multi-pad system. In our proposal, the system was planned as a set of 4–6 force-sensing drum pads connected to a controller that would trigger spatially mapped vibration feedback on a wearable vest. The checkpoint goal was to have the drum measurements completed and to verify that the force sensors and vibration outputs could work together as a functional system.

We were able to record some drum sounds and vibrations, specifically using taiko, and focusing on the difference between small and large drums. In order to record the vibrations, a basic testing setup was created with a stand, a phone, and some string. The string was used to suspend the phone from the stand and isolate it from the ground as much as possible. Then, the stand was placed near the drum and the phone’s accelerometer was used to measure the vibration caused by each drum as it was hit.

Example Measurement:

We then isolated one of the hits for both:

Then, we took a FFT for both and noted which dominant frequencies were present in the graph:

It appears that the large drum requires a much more significant force output at around 25 and 60 Hz, while the small drums requires a force output around 70 and 100 Hz.

So far, we have purchased and tested several of the key materials needed to validate the system. We connected a force sensor and a speaker/vibration module to a Hapkit board and experimented with mounting them into foam board structures to simulate a drum pad surface. This helped us test whether a pad strike could be detected clearly and whether the resulting vibration output was strong enough to feel through a body-contact surface. From these early tests, the force sensor appears usable for detecting impact events, and the vibration output is noticeable enough to continue developing the system. However, more work is still needed to tune the mapping between strike force and vibration intensity so that light, medium, and hard hits feel meaningfully different.

We have met the original goal of testing the force sensors and vibration modules, but we have a lot of work to do on actually developing representative drum profiles. The vibration output does not automatically feel like a realistic drum impact; it will take calibration and experimentation to make each drum type feel distinct. This connects directly to our proposal: different drums should produce different haptic responses, with larger drums mapped more strongly to the chest and smaller drums potentially mapped to the arms or upper body.

Above shows the FSL and coin motor circuit we made, touching the FSL cause the ERM to vibrate, fulfilling one of our requirements for checkpoint 1. We currently have it coded such that the duty cycle amplitude increases linearly with the force applied, which we may change for the final product depending on the sensation we wish to achieve.

Above shows us testing if the motor can be adequately felt on the user if pressed into the body properly. We experienced that yes; the motor can be felt with the right amount of pressure which motivates our next steps of getting straps to hold the motors to the body. We also discovered here that many motors together would be adequate to produce the vibrations we need, which is an easy to produce and cheap option. We ordered a PWM driver with I2C communication in order to be able to control all these motors at once.

Based on what we learned, our current plan is to move toward a parent-board system. The force sensors will likely connect to one Hapkit board or sensor board, which will communicate strike information to a parent Hapkit board. The parent board will then trigger the speaker/vibration modules based on which pad was hit and how hard it was hit. This should make the system easier to organize because the sensing and actuation logic can be separated. Going forward, we expect a significant amount of testing and experimentation to be focused on matching the haptic output to what a user would expect from a drum performance. In particular, we need to tune the vibration profile, intensity scaling, and physical placement so the feedback feels intentional rather than just like a generic buzz.

For Checkpoint 2, our next steps are to wire more of the system together, test multiple sensors, and begin developing the control scheme for proportional haptic response. We also need to compare different actuator placements and output profiles to determine whether each drum type can be distinguished through touch alone. Along with tuning this performance, we are looking to develop the hardware for the vibration motors to ensure good contact on the users body and develop robust drum kits which ensure consistent force readings. This will help us prepare for the final prototype, where the main goal is to make the haptic feedback feel convincing, responsive, and musically meaningful.

Checkpoint 2

Here you will write a few paragraphs about what you accomplished in the project so far. Include the checkpoint goals and describe which goals were met (and how), which were not (what were the challenges?), and any change of plans for the project based on what you learned. Include images and/or drawings where appropriate.

Example Video: https://www.youtube.com/watch?v=i_aLBql4Ufo