Skip to content

Commit 89f8b6b

Browse files
shi-amyshi-amy
committed
meche blogs
1 parent b4c11fa commit 89f8b6b

File tree

15 files changed

+97
-90
lines changed

15 files changed

+97
-90
lines changed

‎Blogs/MechE/eebox.html‎

Lines changed: 36 additions & 16 deletions
Original file line numberDiff line numberDiff line change
@@ -124,26 +124,46 @@ <h2 class="entry-title">
124124
</div> -->
125125
<div class="entry-content">
126126
<p>
127-
One of the first tasks our team worked on was buoy
128-
detection. Most of the navigation courses in Roboboat
129-
require us to identify buoys and then figure out how to
130-
navigate them. Using a ZED camera, we developed the
131-
following algorithmic steps to properly identify buoys
132-
on the course:
127+
The purpose of a custom electronics box is to provide a lightweight, accessible, easily modifiable, cool (temperature-wise), splash-proof housing for Fish ‘N Ships’ electrical components.
133128
</p>
134-
<p>Performs erosion with a segmentation kernel</p>
135-
<p>
136-
Performs dilation with the same segementation kernel
129+
<p><i>Design 1:</i></p>
130+
<p style="text-indent: 50px;">The initial design of the EE box focused on accessibility, modularity, and thermals. It consisted of an ⅛”
131+
aluminum base, ⅛” acrylic walls, removable faceplates, a large “land” lid, and smaller “water” lids. This version of the box condensed the boat’s
132+
sensors and electronics into a single sub-assembly--i.e., its “brains”--that could be removed and tested independent of the hulls. The electronics
133+
were designed to mount to slightly elevated acrylic pegboards (elevated for subterranean wire management). Thermals were managed passively by aluminum
134+
“sleeves” that wrapped completely around the hulls and made direct contact with the box’s aluminum base. Overall footprint was roughly 32”x16”x6.5”
135+
(not counting the height of the sensor mast).
137136
</p>
138-
<p>Converts the image to HSV</p>
139-
<p>
140-
Gets the mask for each color range we are looking
141-
at(red, green, yellow)
137+
<img src="../../Pictures/Blogs/eebox1.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
138+
<p style="text-indent: 50px;">The second iteration of the box was driven by a single design requirement the first design failed to meet: weight.
139+
The original design weighed ~13 lbs, roughly 12% of the team’s weight budget at the time. This egress prompted a spirited discussion of the
140+
necessity of a custom EE box--off the shelf options are cheaper, require less manpower (from the team at least), are rated to depths well
141+
beyond the design requirements of the box, and commonly used by RoboBoat teams. Modifying such boxes--while inelegant--is neither costly
142+
nor difficult, though it does make the box’s original pressure rating irrelevant. The question thus became: can we manufacture a box that
143+
offers a better weight to volume ratio than the leading alternative? And would it be worth the cost? We decided there was a high probability
144+
we could--and that the cost was more than justified by the learning experience.
142145
</p>
143-
<p>
144-
Generates a bounding box for each disjoint blob in the
145-
color range mask
146+
<p><i>Design 2:</i></p>
147+
<p style="text-indent: 50px;">Design two features the elevated peg boards and removable faceplates of the first design, only this time they’re
148+
compressed into a footprint roughly a third the size (12”x16”x8”). To account for this compressed footprint the pegboards were elevated ~4” off
149+
the base (enough room to rotate the average human hand comfortably)--opening up a second layer for mounting components. The focus on weight reduction
150+
meant the old aluminum base with its heat finned cooling system was a non starter.. Fabric--engineered by a fashion industry focused on breathability,
151+
water resistance, and weight--was the obvious replacement. The new box was constructed almost entirely out of an ⅛” plywood frame, and the lid draped
152+
in PolyUrethane Laminate--a lightweight, durable, water resistant cloth commonly used for DIY diapers. Finally, fans, protected by 3D printed shrouds,
153+
were added for increased airflow.
154+
</p>
155+
<img src="../../Pictures/Blogs/eebox2.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
156+
<p><i>Current Design:</i></p>
157+
<p style="text-indent: 50px;">The current design retains many of the core innovations of the previous two--including the elevated peg boards,
158+
fabric lid, and removable faceplates. The primary driver of this iteration was usability feedback from the EE team: a self locating pin was added
159+
to make aligning the lid easier when latching the box shut and to prevent water from pooling during rainy tests; the number of mounting screws per
160+
faceplate was doubled to prevent water from entering the box when rogue waves swept over the deck; 1/32” aluminum L brackets were fastened to the edges
161+
of the acrylic pegboards to prevent the previous bowing/flexing/swaying behavior that made mounting components to the pegboards difficult; compliant hooks
162+
were added to keep the latches in the “upright” position while lowering the lid; and the Jetson was mounted on L-bracket stand-offs to allow for rapid
163+
insertion and removal from the box. Once the wooden seams of the base were caulked with a polyether adhesive the box proved watertight to 16cm (at which
164+
point water entered via the fan out take), well above design spec.
146165
</p>
166+
<img src="../../Pictures/Blogs/eebox3.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
147167
</div>
148168
</main><!-- End #main -->
149169

‎Blogs/MechE/hulls.html‎

Lines changed: 16 additions & 21 deletions
Original file line numberDiff line numberDiff line change
@@ -123,27 +123,22 @@ <h2 class="entry-title">
123123
</ul>
124124
</div> -->
125125
<div class="entry-content">
126-
<p>
127-
One of the first tasks our team worked on was buoy
128-
detection. Most of the navigation courses in Roboboat
129-
require us to identify buoys and then figure out how to
130-
navigate them. Using a ZED camera, we developed the
131-
following algorithmic steps to properly identify buoys
132-
on the course:
133-
</p>
134-
<p>Performs erosion with a segmentation kernel</p>
135-
<p>
136-
Performs dilation with the same segementation kernel
137-
</p>
138-
<p>Converts the image to HSV</p>
139-
<p>
140-
Gets the mask for each color range we are looking
141-
at(red, green, yellow)
142-
</p>
143-
<p>
144-
Generates a bounding box for each disjoint blob in the
145-
color range mask
146-
</p>
126+
<p style="text-indent: 50px;">Our new vehicle, Fish ‘N Ships, features a catamaran design due to its stability and low drag
127+
characteristics. In the initial design, we placed the battery boxes within the hulls to lower the center of mass, decided on
128+
ammo boxes to store the batteries for fireproofing, and used foam as the main material of the hulls since it would be less likely
129+
to sink if the hulls were punctured. However, the final product turned out to be 36lbs, which was much higher than we expected,
130+
since we were trying to keep the overall weight of the vehicle under 70lbs.
131+
</p>
132+
<img src="../../Pictures/Blogs/hulls1.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content; margin-bottom: 30px;">
133+
<p style="text-indent: 50px;">Thus, we began a new round of design with more specific design requirements and tried different
134+
manufacturing techniques. While we still planned on using foam and sealing it with epoxy and fiberglass, we utilized vacuum
135+
bagging technology instead of doing hand layups, since vacuum bagging can spread the epoxy more evenly across the surface, resulting
136+
in less layers (and weight) than manual techniques. We also decided to shorten the hulls to make the boat smaller, which would also
137+
help cut down the weight and make the boat easier to transport. Finally, instead of using ammo boxes, which contributed significantly
138+
to the weight, we opted for tupperware, since they worked well in waterproofing the batteries and were also very lightweight. The current hulls
139+
are only 12lbs total. They are four feet in length, and the entire boat can be easily carried by two people.
140+
</p>
141+
<img src="../../Pictures/Blogs/hulls2.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
147142
</div>
148143
</main><!-- End #main -->
149144

‎Blogs/MechE/propulsion.html‎

Lines changed: 20 additions & 20 deletions
Original file line numberDiff line numberDiff line change
@@ -123,27 +123,27 @@ <h2 class="entry-title">
123123
</ul>
124124
</div> -->
125125
<div class="entry-content">
126-
<p>
127-
One of the first tasks our team worked on was buoy
128-
detection. Most of the navigation courses in Roboboat
129-
require us to identify buoys and then figure out how to
130-
navigate them. Using a ZED camera, we developed the
131-
following algorithmic steps to properly identify buoys
132-
on the course:
133-
</p>
134-
<p>Performs erosion with a segmentation kernel</p>
135-
<p>
136-
Performs dilation with the same segementation kernel
137-
</p>
138-
<p>Converts the image to HSV</p>
139-
<p>
140-
Gets the mask for each color range we are looking
141-
at(red, green, yellow)
142-
</p>
143-
<p>
144-
Generates a bounding box for each disjoint blob in the
145-
color range mask
126+
<p style="text-indent: 50px;">Our previous vehicle only had two thrusters in the rear, which meant we didn’t have strafing or station
127+
keeping abilities. Thus, for Fish ‘N Ships, it was very important to us to use an x-drive configuration (two thrusters in the front
128+
and two thrusters in the back of the hulls). This allowed our new vehicle to strafe and station-keep with ease. However, we didn’t know
129+
the best angle to mount the thrusters, and we wanted to keep it adjustable so that we can test out the best configuration. Therefore,
130+
we designed an attachment on the bottom of the hulls that had holes in 22.5 degree increments, to allow us to easily attach the thrusters
131+
in different positions.
132+
</p>
133+
<img src="../../Pictures/Blogs/propulsion.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
134+
<p style="text-indent: 50px;">Another design consideration we had in mind was to add some sort of protection to the thrusters. In the past,
135+
we could not set the vehicle down without propping it on a platform since the thrusters protruded from the hulls. This made it difficult to
136+
transport and test the boat. Therefore, our team decided to add some thruster cages to allow us to set the boat on the ground.
137+
</p>
138+
<p style="text-indent: 50px;">In our initial design, we mounted two U-bolts for each thruster, but we quickly realized that the U-bolts
139+
were quite heavy, contributing to 10% of the overall vehicle weight. Therefore, we considered different materials and geometry to reduce
140+
the weight. For material, we decided to SLA 3D print using Formlabs Tough 2K resin. As for geometry, two different designs were considered.
141+
The first design weighed a total of 2.4 lbs, and the second design has a total weight of 4.15 lbs. We ended up choosing the first design in
142+
consideration of weight restraints. However, we wanted to make sure that the first design can still withstand a reasonable amount of force,
143+
so we verified with FEA performed on OnShape and physical tests. The results showed that each cage could support over 150lbs, which is more
144+
than sufficient for our design, and now, the cages only contribute to 4% of the total weight.
146145
</p>
146+
<img src="../../Pictures/Blogs/thrustercages.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
147147
</div>
148148
</main><!-- End #main -->
149149

‎Blogs/MechE/sensormast.html‎

Lines changed: 14 additions & 23 deletions
Original file line numberDiff line numberDiff line change
@@ -123,27 +123,18 @@ <h2 class="entry-title">
123123
</ul>
124124
</div> -->
125125
<div class="entry-content">
126-
<p>
127-
One of the first tasks our team worked on was buoy
128-
detection. Most of the navigation courses in Roboboat
129-
require us to identify buoys and then figure out how to
130-
navigate them. Using a ZED camera, we developed the
131-
following algorithmic steps to properly identify buoys
132-
on the course:
126+
<p style="text-indent: 50px;">Our sensor mast provides a stable platform with an unobstructed field of view for the ZED camera and LiDAR to fully utilize the sensors’
127+
capabilities. Our initial design consisted of a central PVC pipe with FDM printed mounts for the LiDAR, ZED, and various other sensors. The pros of
128+
this design was that it was easy/quick to manufacture; however, after thorough testing, we found that the mast exhibited a low-frequency swaying
129+
behavior when the boat was on the water. This interfered with the perception performance of our autonomy system, so we iterated on the design.
130+
The current design features three mounting points instead of two, contributing to a much stabler platform. It is made of ⅛” aluminum box tube
131+
braised into a rigid frame, and it features adjustable height vibration dampers to prevent the swaying behavior.
133132
</p>
134-
<p>Performs erosion with a segmentation kernel</p>
135-
<p>
136-
Performs dilation with the same segementation kernel
137-
</p>
138-
<p>Converts the image to HSV</p>
139-
<p>
140-
Gets the mask for each color range we are looking
141-
at(red, green, yellow)
142-
</p>
143-
<p>
144-
Generates a bounding box for each disjoint blob in the
145-
color range mask
133+
<img src="../../Pictures/Blogs/sensormast1.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
134+
<p style="text-indent: 50px;">The current design features three mounting points instead of two, contributing to a much stabler platform. It is made
135+
of ⅛” aluminum box tube braised into a rigid frame, and it features adjustable height vibration dampers to prevent the swaying behavior.
146136
</p>
137+
<img src="../../Pictures/Blogs/sensormast2.png" style="display: block; margin-left: auto; margin-right: auto;width: fit-content;">
147138
</div>
148139
</main><!-- End #main -->
149140

@@ -169,10 +160,10 @@ <h3>Arcturus</h3>
169160
<div class="col-lg-2 col-md-6 footer-links">
170161
<h4>Useful Links</h4>
171162
<ul>
172-
<li><a href="../index.html">Home</a></li>
173-
<li><a href="../about.html">About us</a></li>
174-
<li><a href="../team.html">Team Members</a></li>
175-
<li><a href="../contact.html">Sponsors</a></li>
163+
<li><a href="../../index.html">Home</a></li>
164+
<li><a href="../../about.html">About us</a></li>
165+
<li><a href="../../team.html">Team Members</a></li>
166+
<li><a href="../../contact.html">Sponsors</a></li>
176167
</ul>
177168
</div>
178169

‎Blogs/blog-mechE.html‎

Lines changed: 11 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -113,20 +113,21 @@ <h2>Mechanical</h2>
113113
<div class="container pt-5 pb-5">
114114
<div class="row content justify-content-center" style="text-align:center">
115115
<h2>Mechanical Engineering</h2>
116+
<h4>Click on the cards below to read more about our subsystems. </h4>
116117
<div class="row" data-aos="fade-up">
117118
<div class="col-lg-4 col-sm-4 py-2">
118119
<a href="MechE/hulls.html" class="card-overlink">
119120
<div class="card shadow" style="width: 100%">
120121
<img
121-
src="../Pictures/Blogs/buoydetection.png"
122+
src="../Pictures/Blogs/hulls2.png"
122123
class="card-img-top"
123124
alt="..."
124125
style="max-height: fit-content; width: auto; margin: 30px 30px 10px 30px; display: block;"
125126
/>
126127
<div class="card-body pb-4">
127128
<h4 class="card-title">Hulls</h4>
128129
<p class="card-text">
129-
Read More
130+
Foundation of our boat
130131
</p>
131132
</div>
132133
</div>
@@ -137,15 +138,15 @@ <h4 class="card-title">Hulls</h4>
137138
<a href="MechE/propulsion.html" class="card-overlink">
138139
<div class="card shadow" style="width: 100%">
139140
<img
140-
src="../Pictures/Blogs/buckboard.jpg"
141+
src="../Pictures/Blogs/propulsion.png"
141142
class="card-img-top"
142143
alt="..."
143144
style="max-height: fit-content; width: auto; margin: 30px 30px 10px 30px; display: block;"
144145
/>
145146
<div class="card-body pb-4">
146147
<h4 class="card-title">Propulsion/Thruster Cages</h4>
147148
<p class="card-text">
148-
Read More
149+
Driving force of our boat
149150
</p>
150151
</div>
151152
</div>
@@ -155,15 +156,15 @@ <h4 class="card-title">Propulsion/Thruster Cages</h4>
155156
<a href="MechE/eebox.html" class="card-overlink">
156157
<div class="card shadow" style="width: 100%">
157158
<img
158-
src="../Pictures/Blogs/pathplanning.png"
159+
src="../Pictures/Blogs/eebox3.png"
159160
class="card-img-top"
160161
alt="..."
161162
style="max-height: fit-content; width: auto; margin: 30px 30px 10px 30px; display: block;"
162163
/>
163164
<div class="card-body pb-4">
164165
<h4 class="card-title">EE Box</h4>
165166
<p class="card-text">
166-
Read More
167+
Electronics protector
167168
</p>
168169
</div>
169170
</div>
@@ -177,15 +178,15 @@ <h4 class="card-title">EE Box</h4>
177178
<a href="MechE/sensormast.html" class="card-overlink">
178179
<div class="card shadow" style="width: 100%">
179180
<img
180-
src="../Pictures/Blogs/buoydetection.png"
181+
src="../Pictures/Blogs/sensormast2.png"
181182
class="card-img-top"
182183
alt="..."
183184
style="max-height: fit-content; width: auto; margin: 30px 30px 10px 30px; display: block;"
184185
/>
185186
<div class="card-body pb-4">
186187
<h4 class="card-title">Sensor Mast</h4>
187188
<p class="card-text">
188-
Read More
189+
Mounting point for sensors
189190
</p>
190191
</div>
191192
</div>
@@ -196,15 +197,15 @@ <h4 class="card-title">Sensor Mast</h4>
196197
<a href="MechE/mechanisms.html" class="card-overlink">
197198
<div class="card shadow" style="width: 100%">
198199
<img
199-
src="../Pictures/Blogs/buckboard.jpg"
200+
src="../Pictures/Blogs/comingsoon.jpg"
200201
class="card-img-top"
201202
alt="..."
202203
style="max-height: fit-content; width: auto; margin: 30px 30px 10px 30px; display: block;"
203204
/>
204205
<div class="card-body pb-4">
205206
<h4 class="card-title">Mechanisms</h4>
206207
<p class="card-text">
207-
Read More
208+
Allow for robotic functions
208209
</p>
209210
</div>
210211
</div>

‎Pictures/Blogs/comingsoon.jpg‎

548 KB
Loading

‎Pictures/Blogs/eebox1.png‎

212 KB
Loading

‎Pictures/Blogs/eebox2.png‎

105 KB
Loading

‎Pictures/Blogs/eebox3.png‎

88.7 KB
Loading

‎Pictures/Blogs/hulls1.png‎

563 KB
Loading

0 commit comments

Comments
 (0)