ENME 351 Final Project - Helmet Hud

Added: 2026-05-12

[00:00:04]Hey everyone, this is my 351 project.

[00:00:07]Let's get to it. Right here on the cart attached to the spindle, we've got a clamped 3D printed part that's got small magnets. Then here, this part is clamped to a fixed um cylinder so it can't rotate. And it's got the Hall effect sensor at the end. Magnet goes right in front of the Hall effect sensor. We have two magnets here for higher resolution.

[00:00:26]Right here we've got our electronics box. Uh inside is Arduino breadboard um and our sixvolt battery attach attached to a 5volt regulator. Here's the potentiometer pin that's going to change our servo. Here's our onoff switch. We've got wiring going all the way soldered together um leading to our helmet. On this helmet here, we've got a beam splitter, 70% transparency, 30% reflective. Got a servo attached to a in place printed 3D printed hinge. And then we've got our 1.3 in OLED display that's going to be reflecting off this beam splitter into your eyes. Let's get to racing.

[00:01:41]So, here we have our electronics box outside of the go-kart. We've got our breadboard, our Arduino, and the 6volt battery was sitting in here. Right after the sixvolt battery, it is wired to the switch to make sure it's not constantly in use uh and draining the battery.

[00:01:56]And then it actually does get directly connected out to the servo because um the Arduino cannot supply enough current for um the servo motor under the load.

[00:02:09]Uh so the server motor is going to see six volts but the rest of these components such as the OLED and the hall effect cannot and the um Arduino cannot take more than five. So that's why after that we've wired in through this 5V regulator um to supply power to everything else in here. Um and everything shares a common ground. Um now without the go-kart um how we're going to be demoing this is with this old 12vt vacuum cleaner motor. Um this is a 12volt power supply. that's going to be connected to the wall and a PWM um to control the speed of that motor because that motor is very fast. So, first let's show uh the servo actuation.

[00:02:47]So, let's turn this on.

[00:02:51]So, the point of the servo is that the angle um between our display and this beam splitter is going to change how it's reflected into your eyes. Um so, we need some finetuning. So, turning the potentiometer here all the way.

[00:03:07]Currently, there's a large dead zone.

[00:03:08]So, if you turn it all the way in one direction, it is going to activate the servo um with very fine tune adjustments for you to react. And now, if we turn it the other way, should go back in at a very slow pace. So, so now we're going to see the processing demo off the cart. So, on.

[00:03:29]And if we turn our motor RPM up and we increase the speed.

[00:03:45]So let's try that again. Um and this uh this speed in miles per hour is purely based on if this wheel was actually driving. If this was the size of the go-kart wheel, uh this would be our speed.

[00:03:59]fast. You can see the RPM here at this very low PWM is already almost at 2,000 RPM. And here we're actually keeping track of the pulse of our servo. So, if we start adjusting that, pulse is going to change gradually. If we adjust it the other way, pulse is going to start increasing. 1500 is the pulse home.

[00:04:20]So, we're reading RPM. Increase it.

[00:04:25]And it's going to reset when we reach the end.