Difference between revisions of "Prototyping Guide"

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= Mandatory 3D Printing for all SLDPs =  
= Introduction =  


All SLDP groups will be required to design and 3D print a one-color logo. All specifications outlined in the Logo specification section must be met. All SLDP groups may design and print a two-color logo to meet the mandatory 3D printing requirement and will receive extra credit for using two colors. Deadlines for this mandatory print are outlined in the deadlines section below and can be found under each individual SLDP page.
== What is Prototyping? ==


Groups must submit an STL file of a logo through the [https://eg.poly.edu/3DPrinting.php 3D Printing Submission] portal by Benchmark A, receive approval from a ProtoLab TA by Benchmark B, and have it printed by Commissioning. '''<span style="color: red;">The printed logo is a requirement for commissioning, and failure to do so will result in point penalties on the project grade.</span>'''
It’s in the name itself – “Proto” meaning “early” and “type” meaning “thing.” A prototype is an early version of the product that is made cheaply and efficiently to prove that your idea actually works (we call that “proof of concept”). You don’t want to waste money making something useless.  


= ProtoLab Schedule =
== “Ideation” and “Brainstorming” ==
* Monday: 2 PM to 6 PM
* Tuesday through Friday: 12 PM to 6 PM
<!--= Mandatory 3D Printing for HIR =  


For all students working on the Housing & Innovation in Revit (HIR) project, there will be an additional mandatory 3D print required for commissioning. Groups must submit a .STL file of a single floor plan through the 3D Printing Submission portal and receive approval from a ProtoLab TA by <b>Benchmark B</b>. The printed floor plan is a <b>requirement</b> for commissioning, and failure to do so will result in point penalties on the project grade. HIR projects will have two mandatory prints:
Before you get to the prototyping stage, you have to figure out what it is you’re making. This is the “Ideation” stage. A good strategy here is to start from your problem and work towards a solution. Ask yourself, “What’s an issue people are dealing with? Who is the underrepresented consumer? Where is there a gap in the market?” In fact, don’t just ask yourself, ask other people from diverse backgrounds with unique experiences. Do research to see what’s already out there. Look critically at the world around you.  
* One floor plan
* One single color logo (or an additional floor plan which will count as extra credit).-->


= 3D Printing Extra Credit for HIR =
Once you’ve answered the “what should it do,” '''prototyping''' answers the “How will it work?” (This can refer to the entire product or a specific mechanism within the product).


For HIR groups, 3D printing extra credit is awarded for 3D printing one-floor plan of the exterior of your building. Submit an STL file of a single floor plan through the 3D Printing Submission portal and receive approval from a ProtoLab TA to get it printed before Commissioning.
A few key questions are:


= Logo Specifications =  
=== What conditions will my design experience? ===


* Maximum material weight does not exceed 15 g total
This includes temperatures, loads (tensions, compressions, shear forces), repetitive motion, friction, human interaction, contact with body parts, contact with liquids, rotations, and torque.
* Can be one or two colors
** One-color logos are mandatory for all SLDP groups
** Two-color logos are extra credit for all SLDP groups
** Two STL files are required for two-color logos, submitted as a .zip file on the website
* Logos must be integrated with your project in some way
* Must be original content
** Cannot be exclusively text or a simple geometric shape
* Must be exported as a .STL with correct scaling (make sure the document units are set to mm before exporting)


[[Image:3D_Good.png|thumb|center|500px|Figure 1: Example of a good logo – original graphics and represents the project]]
=== What dimensions will my design need to be? ===


[[Image:3D_Bad.png|thumb|center|500px|Figure 2: Example of a bad logo – easily recreatable and tells you nothing about the project]]
Does it have to be wearable? Does it have to stand on its own? Does it have to fit a mid-sized cat inside it?


= Software =
=== What components will my design need? ===


To design your logo you will need any CAD software as well as CURA. There are many options for software that can be used, the only necessary feature is that the software can export files as an .STL (stereolithography) extension. Some examples of recommended software:
This includes sensors, motors, microcontrollers, cameras, LEDs, LCD screens, micro-computers (like Raspberry Pi’s), speakers, and any and all electrical components which your physical design must house.  
* Autodesk Fusion 360 – Free student edition
* Autodesk Inventor – Free student edition
* 123D – Free (Online)
* TinkerCAD – Free (Online)
* Blender – Free (Open source)
* OpenSCAD – Free (Open source)
* Solidworks – Available in NYU computer labs
* Rhinoceros – Free evaluation available for MacOS


To make a 2 color design you will need to save your logo in two separate .STL files (one for each color) and submit both as a .zip file to the website. The two files are then imported into CURA and aligned, with separate extruders selected for each color.
=== And, most importantly, how much time and money do I have? ===
<!--=== Housing in Revit Models: ===


* One <b>mandatory</b> floor plan for commissioning
In EG 1004, you usually have three months and 100 dollars. This greatly impacts what you can reasonably use in your prototype.
* Maximum two additional 3D printed floor plans for extra credit
* Maximum print size 7 x 8 x 7 in
** Wall height must be to scale with the floorplan
** If printing multiple floors, second and third floors must nest on top of first floor
*** Elevator shafts aligning, stairs aligning, etc.
* Original designs
** Must be different from other groups' submissions
* Must be .STL extension
** Refer to Revit How To Guide for assistance with STL conversion: https://manual.eg.poly.edu/images/7/78/Revit_How_To_Guide.pdf-->


= Design Considerations =
== Design → Computer-Aided Design ==


* Make a flat bottom: A large flat bottom increases the adhesion between the build platform and the part, keeping the part from shifting around during a print.
CAD, or Computer-Aided Design, has two advantages: The first is to make neat, precise representations of a physical product before construction, which allows you to test the viability of a design before you break out the hack saw. The second is to generate files that can be 3D printed, laser cut, or CNC milled.  
* Keep overhangs close to 45 degrees: Each layer of a 3D print needs to be supported from below. You can avoid adding additional supports to a print if all the overhanging parts are at no more than a 45-degree angle from vertical.
* Avoid thin walls and thin columns: Thin walls and columns often do not come out well. The thickness of a thin wall should be a multiple of 0.35 mm. Thin columns will usually come out distorted because they melt under the nozzle.


= Advanced Prints =
It is also useful to use CAD software (like Fusion 360, TinkerCAD, Eagle, or Fritzing) to design and test the circuit that connects your components, and creates a neat, legible representation of it for reference.


For any group considering an advanced print through the MakerSpace:
An additional realm of CAD is Building Information Modeling software, also referred to as BIM. BIM software and facilitators (like Revit and AutoCAD respectfully) enable users to design, simulate, collaborate, and budget structures prior to implementation and construction.
* One person in the group must have completed the training on the machine prior to making the request.
* Groups '''must''' fill out the [https://docs.google.com/forms/d/e/1FAIpQLSdDlJAxRvHlST05xUDVK7lyM6SYLEmTfvIKbqKts-tEB8QhWQ/view| MakerSpace/EG-1003 Print Request form] and get approval from a ProtoLab TA '''before''' going to the MakerSpace to complete the print.
** For approval, you must present the file that you wish to print as well as making sure the specifications of the print line up with what was entered on the form.
* After filling out the form, you will have a week to complete the purchase otherwise it will be voided.


= Submission and General Guidelines =


* Submission of your 3D designed parts will take place through the EG website using the “3D Printing Submission” tab of the left menu. <b>DO NOT USE THE NORMAL SUBMISSION TAB</b>. Submit your .STL files and .gcode files in a .zip file to the website.
== Creation → Manufacturing Methods ==
* Make sure to submit an STL with the correct scaling.
** If you choose to build your model in inches, remember to convert to millimeters before saving the STL
* Please name the .STL files in the format <b>Section_Project_PrintType_FileNumber</b> i.e. A1_HIR_Logo_1, and the .gcode in the format <b>Section_Project_PrintType</b>. Please make sure the colors selected match the file number of the .STL and selected extruder in the cura setup (i.e. A1_HIR_Logo_1 should match your Color 1 option and Extruder 1 in your Cura setup).
* After your submission has been received, you will need to meet with a Proto TA to have your print approved during Protolab hours.
* If you are a <b>RAD group</b>, you have the option to self-print your design <b>(if it is NOT a Logo)</b> at the MakerSpace. If you are a RAD group, please only submit non-logo prints to the website if you want Protolab to print your design. The same applies to LAZ and MRR group wanting to manufacture a robot part or course modification.
* You can check the status of your print from the “3D printing Submission” tab. “Pending” means your print is in the process of being approved. “Approved” means your print is in the queue to be printed (“Denied” means you will need to make changes and resubmit.) “Printed” means your print is finished. “Picked Up” means your print has been delivered.
* As you are submitting your 3D designs for your logos, course modifications, or robot parts, please keep in mind the requirements posted on the EG Manual. If you have any further questions, please email prototyping@eg.poly.edu.
* RAD: Prototyping TAs will have the final decision over whether or not a part should be 3D printed or manufactured using another method. Also, while some parts submitted for 3D printing may be taken from preexisting designs online, your end result should still be an original design in order to not violate NYU’s academic honesty guidelines.


= Deadlines =
Below you’ll find a list of possible manufacturing methods available to you. The ones you’ll use depend on the specifications of your design. For example, if it’s a housing unit made out of large, flat pieces, laser cutting might be the right method, because it’s primarily two-dimensional. If it’s a small, light device with a unique shape, 3D printing could be useful since it builds the model layer by layer out of polymer filament. If it needs to be heat resistant or undergo friction, CNC milling might be helpful because there’s a broader range of possible materials. If it’s bulkier but needs to be tough, woodworking is a viable option. Soft, flexible, cozy, and generally inviting? Try sewing.


* <b>Initial STL file submission for mandatory prints is due by Benchmark A (Week 7)</b>
===Do I have to design everything from scratch?===
** The 3D printing process can take multiple revisions, you are required to submit the first attempt by Benchmark A, but you will be allowed to make any modifications until the final deadline of Benchmark B.
* <b>STL file approval for prints is due by Benchmark B (Week 10)</b>
** You must meet with a Protolab TA during Protolab hours to get your print approved. You cannot get your print approved without meeting with a Protolab TA. Your print will not be processed if it is not approved.
** If you miss the Benchmark B deadline, subsequent submissions will not be considered. All submissions must be approved by this deadline (with very limited exceptions).
* <b>Printed part by Commissioning Deadline (Week 14)</b>
* You must have picked up your printed part by commissioning.
* These deadlines are applicable to mandatory logo prints, extra credit prints fulfilling the mandatory logo print requirement, and all SLDPs extra credit prints.


= ProtoLab Schedule =
Don’t reinvent the wheel; plenty of components already exist (for example: water pumps, safety goggles, a large broom, an insulated mug, a succulent, pieces of foam pool noodles) that can be used in a prototype. This guide covers the manufacturing of original parts custom-made for the unique needs of your product.


* Monday 2PM to 6PM
==To Solder or not to Solder, that is the question==
* Tuesday 12PM to 6PM
 
Soldering is a method of creating permanent connections within a circuit onto a flat protoboard. A soldered circuit is usually much more compact than one using a breadboard and wires for temporary connections. The components can be connected directly using much smaller lengths of wire or lines of conductive metal connections known as “track solder.” This is especially useful in wearable devices and other designs that need to be picked up and handled or moved around, where a temporary connection would be too fragile.
 
= General Tips =
 
*Have a plan. Know your dimensions, know your circuit diagram, know your needed components, and know your environments. 
*Research, research, research.
*Be ready and willing to learn.
*Start with the simplest solution first.
*It’s okay to pivot. Sometimes the original design will hit snags nobody could anticipate. Adapt, find a new approach, go back to the ideation stage if you need to.
*It’s an iterative process. Things will probably never work the first, second, or third time.
*If you get stuck, don’t be afraid to reach out to other people.
*Have fun and be yourself.
 
= Manufacturing Methods =
The primary manufacturing processes available to EG 1004 students are listed below:
 
{| class="wikitable"
|+ Available At EG1004 Protolab/Open Lab
!Name!!Advantages!!Disadvantages!!Requirements
|-
 
|style="text-align: left;"|[https://www.hubs.com/knowledge-base/what-is-fdm-3d-printing/ Basic 3D Printing (FDM)] (PLA is the default which is hard and inflexible, TPU, which is more rubbery and bendable, is available upon request)||style="text-align: left;"|<b>Advantages</b>: cheap, relatively easy to learn, freedom of design in shape||style="text-align: left;"|<b>Disadvantages</b>: plastic material, precision of about 0.5 mm realistically, designs built layer by layer from single extrusion onto a plate so be mindful of holes, overhangs||style="text-align: left;"|Print must be approved by Protolab TAs
 
|-
 
|style="text-align: left;"|[https://www.makerspaces.com/how-to-solder/ Soldering]||style="text-align: left;"|<b>Advantages</b>: Permanent connections, neater, compact circuit, durability/longevity||style="text-align: left;"|<b>Disadvantages</b>: Difficult to undo once soldered, errors can lead to unusable circuit or damaged components||style="text-align: left;"|Additional Training from EG1004 Open Lab required
 
|-
|}
 
{| class="wikitable"
|+ [https://makerspace.engineering.nyu.edu/training-and-reservations/ Available at Makerspace]
'''Must be approved by RAD Mentor and submitted via request form on EG website. Access to Makerspace tool requires [https://makerspace.engineering.nyu.edu/orientation/ General Safety Orientation]'''
!Name!!Advantages!!Disadvantages!!Requirements
|-
|style="text-align: left;"|Basic 3D Printing – PLA available, TPU available, Water soluble support PVA available||style="text-align: left;"|<b>Advantages</b>: See description above, no protolab approval needed, opportunity to operate a 3D printer independently||style="text-align: left;"|<b>Disadvantages</b>: See description above, strict time limits at the MakerSpace, no one will retry your print if it fails unlike in the protolab||style="text-align: left;"|Only MakerSpace Safety Training and Introduction required (this training is an EG1004 course requirement)
 
|-
 
|style="text-align: left;"|[https://www.thesprucecrafts.com/getting-started-in-woodworking-3536535 Woodworking]||style="text-align: left;"|<b>Advantages</b>: Toughness, creative freedom, no need for software or machinery||style="text-align: left;"|<b>Disadvantages</b>: Slack of precision, limitations in possible shapes, possibility of injury||style="text-align: left;"|Training recommended for power tools but not mandatory; No reservation needed; material may need to be purchased
 
|-
 
|style="text-align: left;"|[https://wp.nyu.edu/nyushanghai-fabrication-lab/singer-sewing-machine-tutorial/ Sewing]||style="text-align: left;"|<b>Advantages</b>: Good life skill, fabric use, flexibility, done by hand||style="text-align: left;"|<b>Disadvantages</b>:  can be difficult to learn, harder to design/represent in CAD.||style="text-align: left;"|Training recommended for machines but not mandatory; no reservation needed; material may need to be purchased; (scrap is usually available for free)
 
|-
 
|style="text-align: left;"|[https://www.hubs.com/blog/laser-cutting/ Laser Cutting]||style="text-align: left;"|<b>Advantages</b>: works for larger scale pieces than 3D printed designs, strong and rigid, precise.||style="text-align: left;"|<b>Disadvantages</b>: limited to 2D, may require Adobe Illustrator||style="text-align: left;"|Requires additional training; material sheets may need to be purchased; Reservation needed for machines
 
|-
 
|style="text-align: left;"|[https://www.hubs.com/knowledge-base/what-is-sla-3d-printing/ Advanced 3D Printing (SLA)]||style="text-align: left;"|<b>Advantages</b>: very precise, durable resin material, uses a laser which allows for intricacies in shapes without the need for support/adhesion layers||style="text-align: left;"|<b>Disadvantages</b>: More expensive, harder to operate, often unnecessary depending on the complexity of the design||style="text-align: left;"|Requires additional training; material bricks may need to be purchased; Reservation needed for machines
 
|-
 
|style="text-align: left;"|[https://www.minimillr.com/cnc-routing-process/ CNC Routing] & [https://www.hubs.com/knowledge-base/cnc-machining-manufacturing-technology-explained/ CNC Milling]||style="text-align: left;"|<b>Advantages</b>: Subtractive, not additive, can use metals and waxes, able to do PCB (Printed Circuit Board) manufacturing||style="text-align: left;"|<b>Disadvantages</b>: Additional software skills (Eagle), more expensive||style="text-align: left;"|Requires additional training; material bricks may need to be purchased; Reservation needed for machines
 
|-
|}
 
= Example Projects =
 
The following projects are example uses of what one can manufacture using CAD and some of the methods discussed above.
 
[[Image:Example_Project_1.png|600px|thumb|center|Servo Connector (Left), LCD Screen Holder (Right) Former EG Students]]
 
These are devices designed to hold electrical components and attach them to the rest of the build.
 
[[Image:Example_Project_2.png|600px|thumb|center|Stepper Arm (Left), Wrist Device (Right), Former EG Students]]
 
These are designs that interact with the surrounding environment. On the left is a swiping arm attached to a stepper motor which can rotate and provide a delicate push. On the right is a unit molded to the shape of a human wrist. The slits on the side are for fabric straps to secure the unit onto the user.
 
[[Image:Example_Project_3.png|600px|thumb|center|Claw (Left), Curtain (Right), Former EG students]]
 
The claw uses both 3D printed parts and standard screws, nuts, and bolts as connectors. The curtain has a woodworked (sawed and screwed) unit with 3D printed attachments.
 
[[Image:Example_Project_4.png|500px|thumb|center|Lasercut Housing Unit, Former EG Student]]
 
This is a unit assembled using laser cut parts; the holes in the top are for wires and sensor connections.

Revision as of 17:35, 20 September 2022

Introduction

What is Prototyping?

It’s in the name itself – “Proto” meaning “early” and “type” meaning “thing.” A prototype is an early version of the product that is made cheaply and efficiently to prove that your idea actually works (we call that “proof of concept”). You don’t want to waste money making something useless.

“Ideation” and “Brainstorming”

Before you get to the prototyping stage, you have to figure out what it is you’re making. This is the “Ideation” stage. A good strategy here is to start from your problem and work towards a solution. Ask yourself, “What’s an issue people are dealing with? Who is the underrepresented consumer? Where is there a gap in the market?” In fact, don’t just ask yourself, ask other people from diverse backgrounds with unique experiences. Do research to see what’s already out there. Look critically at the world around you.

Once you’ve answered the “what should it do,” prototyping answers the “How will it work?” (This can refer to the entire product or a specific mechanism within the product).

A few key questions are:

What conditions will my design experience?

This includes temperatures, loads (tensions, compressions, shear forces), repetitive motion, friction, human interaction, contact with body parts, contact with liquids, rotations, and torque.

What dimensions will my design need to be?

Does it have to be wearable? Does it have to stand on its own? Does it have to fit a mid-sized cat inside it?

What components will my design need?

This includes sensors, motors, microcontrollers, cameras, LEDs, LCD screens, micro-computers (like Raspberry Pi’s), speakers, and any and all electrical components which your physical design must house.

And, most importantly, how much time and money do I have?

In EG 1004, you usually have three months and 100 dollars. This greatly impacts what you can reasonably use in your prototype.

Design → Computer-Aided Design

CAD, or Computer-Aided Design, has two advantages: The first is to make neat, precise representations of a physical product before construction, which allows you to test the viability of a design before you break out the hack saw. The second is to generate files that can be 3D printed, laser cut, or CNC milled.

It is also useful to use CAD software (like Fusion 360, TinkerCAD, Eagle, or Fritzing) to design and test the circuit that connects your components, and creates a neat, legible representation of it for reference.

An additional realm of CAD is Building Information Modeling software, also referred to as BIM. BIM software and facilitators (like Revit and AutoCAD respectfully) enable users to design, simulate, collaborate, and budget structures prior to implementation and construction.


Creation → Manufacturing Methods

Below you’ll find a list of possible manufacturing methods available to you. The ones you’ll use depend on the specifications of your design. For example, if it’s a housing unit made out of large, flat pieces, laser cutting might be the right method, because it’s primarily two-dimensional. If it’s a small, light device with a unique shape, 3D printing could be useful since it builds the model layer by layer out of polymer filament. If it needs to be heat resistant or undergo friction, CNC milling might be helpful because there’s a broader range of possible materials. If it’s bulkier but needs to be tough, woodworking is a viable option. Soft, flexible, cozy, and generally inviting? Try sewing.

Do I have to design everything from scratch?

Don’t reinvent the wheel; plenty of components already exist (for example: water pumps, safety goggles, a large broom, an insulated mug, a succulent, pieces of foam pool noodles) that can be used in a prototype. This guide covers the manufacturing of original parts custom-made for the unique needs of your product.

To Solder or not to Solder, that is the question

Soldering is a method of creating permanent connections within a circuit onto a flat protoboard. A soldered circuit is usually much more compact than one using a breadboard and wires for temporary connections. The components can be connected directly using much smaller lengths of wire or lines of conductive metal connections known as “track solder.” This is especially useful in wearable devices and other designs that need to be picked up and handled or moved around, where a temporary connection would be too fragile.

General Tips

  • Have a plan. Know your dimensions, know your circuit diagram, know your needed components, and know your environments.
  • Research, research, research.
  • Be ready and willing to learn.
  • Start with the simplest solution first.
  • It’s okay to pivot. Sometimes the original design will hit snags nobody could anticipate. Adapt, find a new approach, go back to the ideation stage if you need to.
  • It’s an iterative process. Things will probably never work the first, second, or third time.
  • If you get stuck, don’t be afraid to reach out to other people.
  • Have fun and be yourself.

Manufacturing Methods

The primary manufacturing processes available to EG 1004 students are listed below:

Available At EG1004 Protolab/Open Lab
Name Advantages Disadvantages Requirements
Basic 3D Printing (FDM) (PLA is the default which is hard and inflexible, TPU, which is more rubbery and bendable, is available upon request) Advantages: cheap, relatively easy to learn, freedom of design in shape Disadvantages: plastic material, precision of about 0.5 mm realistically, designs built layer by layer from single extrusion onto a plate so be mindful of holes, overhangs Print must be approved by Protolab TAs
Soldering Advantages: Permanent connections, neater, compact circuit, durability/longevity Disadvantages: Difficult to undo once soldered, errors can lead to unusable circuit or damaged components Additional Training from EG1004 Open Lab required
Available at Makerspace Must be approved by RAD Mentor and submitted via request form on EG website. Access to Makerspace tool requires General Safety Orientation
Name Advantages Disadvantages Requirements
Basic 3D Printing – PLA available, TPU available, Water soluble support PVA available Advantages: See description above, no protolab approval needed, opportunity to operate a 3D printer independently Disadvantages: See description above, strict time limits at the MakerSpace, no one will retry your print if it fails unlike in the protolab Only MakerSpace Safety Training and Introduction required (this training is an EG1004 course requirement)
Woodworking Advantages: Toughness, creative freedom, no need for software or machinery Disadvantages: Slack of precision, limitations in possible shapes, possibility of injury Training recommended for power tools but not mandatory; No reservation needed; material may need to be purchased
Sewing Advantages: Good life skill, fabric use, flexibility, done by hand Disadvantages: can be difficult to learn, harder to design/represent in CAD. Training recommended for machines but not mandatory; no reservation needed; material may need to be purchased; (scrap is usually available for free)
Laser Cutting Advantages: works for larger scale pieces than 3D printed designs, strong and rigid, precise. Disadvantages: limited to 2D, may require Adobe Illustrator Requires additional training; material sheets may need to be purchased; Reservation needed for machines
Advanced 3D Printing (SLA) Advantages: very precise, durable resin material, uses a laser which allows for intricacies in shapes without the need for support/adhesion layers Disadvantages: More expensive, harder to operate, often unnecessary depending on the complexity of the design Requires additional training; material bricks may need to be purchased; Reservation needed for machines
CNC Routing & CNC Milling Advantages: Subtractive, not additive, can use metals and waxes, able to do PCB (Printed Circuit Board) manufacturing Disadvantages: Additional software skills (Eagle), more expensive Requires additional training; material bricks may need to be purchased; Reservation needed for machines

Example Projects

The following projects are example uses of what one can manufacture using CAD and some of the methods discussed above.

Servo Connector (Left), LCD Screen Holder (Right) Former EG Students

These are devices designed to hold electrical components and attach them to the rest of the build.

Stepper Arm (Left), Wrist Device (Right), Former EG Students

These are designs that interact with the surrounding environment. On the left is a swiping arm attached to a stepper motor which can rotate and provide a delicate push. On the right is a unit molded to the shape of a human wrist. The slits on the side are for fabric straps to secure the unit onto the user.

Claw (Left), Curtain (Right), Former EG students

The claw uses both 3D printed parts and standard screws, nuts, and bolts as connectors. The curtain has a woodworked (sawed and screwed) unit with 3D printed attachments.

Lasercut Housing Unit, Former EG Student

This is a unit assembled using laser cut parts; the holes in the top are for wires and sensor connections.