Project: Olympus - a Model Rocketry Electronic Payload Project

by Austin_Aerospace_Education in Outside > Rockets

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Project: Olympus - a Model Rocketry Electronic Payload Project

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Project: Olympus is a model rocketry engineering project to introduce the concept of building a payload model rocket kit and creating a custom designed electronic payload. I want to show that anyone can create an interesting rocketry science/engineering project using "off the shelf" model rocket kits and electronic components that are readily available. It continues our series of projects combining model rocketry with micro controllers to create real research and engineering projects on a small scale.

For a more detailed account of the entire project, we have created the “Project: Olympus” project manual. The project manual is over 130 pages and contains everything in this Instructable plus more detailed descriptions of what I did and how I did things. There are more pictures showing the various processes. The complete Arduino code is included, a listing of all the parts necessary and even instructions on how to create the necessary vent holes for accurate altimeter pressure readings.

I cover how to create the 3D printed stand for the rocket and discuss the differences between the Scientific Method and the Engineering Process. I provide an introduction to the purpose and use of engineering notebooks. As you can see, the project manual contains much more information than what we could ever have provided in this Instructable (https://rocketryjournal.wordpress.com/wp-content/uploads/2024/11/project-olympus.pdf).

The manual is free of charge and can be downloaded from our Project Manuals page on the Rocketry Research Journal web site. There you can find project manuals on Project: Icarus, Project: Vulcan, the Arduino Launch Control System, the Arduino Primary Avionics Module (A-PAM) and more (https://rocketryjournal.wordpress.com/project-manuals/).

You can find our Tinkercad files at https://www.tinkercad.com/things/iY6COkklnYd.

You can view our YouTube page that contains videos covering all aspects of building the Olympus rocket and the avionics package (https://www.youtube.com/@AustinAerospace/playlists).

You can download the full Arduino source code here or from our SourceForge page (https://sourceforge.net/projects/olympus-project/). At our SourceForge repository you can find not only the code for the Olympus Project, but our other projects including Project Icarus, Flight Logs database, Rocketry Research Assistant software, Arduino Primary Avionics Module (A-PAM) and more (https://sourceforge.net/u/austinaerospace/profile/).

Finally, for other model rocketry projects, technical reports, project manuals and more, check out our blog and web site at https://rocketryjournal.wordpress.com/

Supplies

Primary Items

Estes Olympus Payload Model Rocket Kit

  1. Hobby Lobby stores
  2. https://www.hobbylobby.com/Crafts-Hobbies/Hobbies-Collecting/Rockets/Olympus-Flying-Model-Rocket-Kit/p/80971713


ELEGOO Nano Board CH 340/ATmega+328P

  1. Amazon
  2. https://www.amazon.com/gp/product/B0713XK923/


HiLetgo Micro SD TF Card Adapter Reader Module 6Pin SPI Interface

  1. Amazon
  2. https://www.amazon.com/gp/product/B07BJ2P6X6


7.4V 2S 200mAh 20C LiPO Battery JST Plug and USB Charger

  1. Amazon
  2. https://www.amazon.com/gp/product/B07MW2L96L


CHANZON 5mm RGB Multicolor LED Diode LightsThrough-Hole Resistors - 220 ohm 5% 1/4W - Pack of 25

  1. Amazon
  2. https://www.amazon.com/Tricolor-Multicolor-Lighting-Electronics-Components/dp/B01C19ENDM


220Ω Resistors (Need 3)Through-Hole Resistors - 220 ohm 5% 1/4W - Pack of 25

  1. Adafruit
  2. https://www.adafruit.com/product/2780


Gikfun GY-68 BMP180 Barometric Pressure Temperature Sensor Module

  1. Amazon
  2. https://www.amazon.com/gp/product/B07Q3PQ81R


HiLetgo 3pcs GY-521 MPU-6050 MPU6050 3 Axis Accelerometer Gyroscope Module

  1. Amazon
  2. https://www.amazon.com/gp/product/B00LP25V1A


HATCHBOX 1.75mm Orange PLA 3D Printer Filament-Orange

  1. Amazon
  2. https://www.amazon.com/gp/product/B00J0EE1D4


LitOrange 320PCS M2 Male Female Nylon Hex Spacer Standoff Screw Nut Assorted Assortment Kit

  1. Amazon
  2. https://www.amazon.com/gp/product/B07D78PFQL


Black Nylon Machine Screw and Stand-off Set – M2.5 Thread

  1. Adafruit
  2. https://www.adafruit.com/product/3299


Black Nylon Machine Screw and Stand-off Set – M3 Thread

  1. Adafruit
  2. https://www.adafruit.com/product/4685


Other Items

  1. Paint
  2. Masking Tape
  3. Wood Glue
  4. Solder
  5. DuPont Connectors
  6. Wire - Assorted colors
  7. Model rocket launch equipment and supplies

Disclaimer

Project: Olympus is something you build, use and interpret entirely at your own risk. It has been designed in good faith to help educate the rocketeer about rocketry and electronic payloads, and to explore how that data might be used for research. However, this is a pilot project. Consequently, I cannot be held responsible for any losses or damages caused by reading or misreading the project instructions or constructing any components of this project. Please do not build this project if you are not comfortable with these terms of use.

The Olympus Model Rocket Kit

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The model rocket kit we are using is the Estes Olympus payload model. It is sold through Hobby Lobby stores or through their web site (https://www.hobbylobby.com/Crafts-Hobbies/Hobbies-Collecting/Rockets/Olympus-Flying-Model-Rocket-Kit/p/80971713). It retails for $14.99. The model is just over 29-inches tall and 1.75-inches in diameter. It can fly on a variety of motors including D12-3, E12-4, D12-5, Or E12-6.

A-PAM: the Electronic Payload

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Creating the Olympus Electronic Payload - Part 1 "Objectives and Design"

The electronic payload that we will be building in this project is an altimeter with an inertial measurement unit. The payload is created using the Arduino Primary Avionics Module (A-PAM) and then adding the necessary hardware and software for the altimeter and the inertial measurement unit (IMU).

We will be using an Arduino Nano as the primary microcontroller. The Arduino Nano makes a great entry level board and it is readily available from a variety of sources. It has a large support network behind it including numerous web sites that offer advice, sample code, insight into the inner workings of the board and more.

Project Planning

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As with most projects you start by sitting down and figuring out exactly what you want the project to do. What is the end goal or primary objective? What tasks need to be performed successfully for the project to be successful?

Project: Olympus is primarily an engineering project, much like Project: Icarus. Where Project: Icarus was designed to test the temperatures inside a model rocket, Project: Olympus is designed to test electronic payload attachments connected to the Arduino Primary Avionics Module (A-PAM). For this project we are going to be testing two specific sensors; an atmospheric pressure sensor to detect altitude and an Inertial Measurement Unit to test g-forces and rocket spin rates.

There are several ways to track this project. You can keep a written notebook and write down your ideas, the tasks that need to be accomplished, etc. You could also keep the same information on your computer. You might use a spreadsheet or document to keep track of things. Another option would be to use a Project Management program. Some of these software programs are quite involved and can be expensive. Don't forget to look at open source options that can be more than adequate to meet your needs. I used an early version of our own Rocketry Research Assistant to start tracking the planning and progress of this project.

Objectives and Payload Components

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With the basic planning and objectives of the project determine, it is time to discuss the design, construction and software development of the electronic payload for the Olympus Project. The objectives state that we want to track altitude, spin rate and G-forces on the rocket. These objectives help us determine what sensors will be needed to meet the goals of the project. Therefore we know we will need an atmospheric pressure sensor and an IMU. Knowing the type of sensor needed, we can select the specific sensor based on criteria such as the ability of the sensor to do the job, the availability of the sensor and the cost involved. The objectives and basic planning are what start you down the path to a successful project. Don’t skip this very important step.

A-PAM

In our objectives we stated that we would use the Arduino Primary Avionics Module or A-PAM as the foundation for the electronic payload. The A-PAM module provides power for the system, a microcontroller to conduct sensor readings and other tasks, a microSD card to record the data, and incorporates a RGB LED lamp that can be used to provide status messages in the field. It provides the foundational components for the overall avionics system and because we have used it on a previous project, it has the added bonus of knowing that it works.

The A-PAM is designed to be connected to a payload module/sensor array. That sensor module will consist of a pressure sensor that is used as an altimeter and an Inertial Measurement Unit (IMU) to record roll, pitch and yaw rates of the rocket as well as acceleration on all three axis.

Altimeter

The BMP180 is a sensor designed to measure barometric pressure or atmospheric pressure. The BMP180 senses that pressure and provides that information in digital output to our Nano. Temperature will affect the pressure and needs to be taken into account. By calculating the difference in pressure and temperature between the launch pad and during flight, we can determine altitude over time.

Inertial Measurement Unit

The MPU-6050 IMU (Inertial Measurement Unit) is a 3-axis accelerometer and 3-axis gyroscope sensor. The accelerometer measures the gravitational acceleration, and the gyroscope measures the rotational velocity. This will provide us with the G-force experienced by the rocket, as well as the roll rate.

Launch Vehicle

By adding an electronic payload to the launch vehicle, I knew that could impact the performance of the Olympus rocket. Using available information we entered the information into OpenRocket and then ran several simulations. Since the results were encouraging, it was decided to continue with the project using this rocket.

Avionics Design

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With all of the electronic components identified we can begin to design the avionics system.

Fritzing Drawings

I designed the avionics package using an open source program called Fritzing (https://fritzing.org). The software allows me to draw out the components and the connections. By drawing out the system first I can make sure that everything fits the available number of pins and that the components will integrate with the Arduino.

A-PAM and Sensor Package

You can see in the development drawing the A-PAM, the RGB status lamp, microSD card module and the Arduino Uno (used during development) along with the two sensors; the MPU6050 IMU motion sensor, and the BMP180 pressure sensor. The drawing shows a couple of interesting things about these sensors.

The BMP180 is using 3.3V while the MPU6050 is using 5V. The BMP180 cannot use 5V and will burn up if it is plugged into a 5V system. Make sure that you keep it's power separate.

Second is that both the BMP180 and the MPU6050 are tied together, with one line is marked “SCL” and the other marked “SDA. These lines go to similar marked pins on the Nano. SDA and SCL are the ports used as part of the I2C (pronounced “eye-squared-sea”) communications protocol. This is how these two sensors will “talk” to the Nano. This is different from the Serial Peripheral Interface (SPI) protocol used by the microSD card.

Breadboard Development

With the Fritzing drawings as a guide, we can begin to layout the electronics on our breadboard.

In the pictures you can see our Uno development board on the left, and the A-PAM components and sensor package on the right. The other photos show the various components and their connections on the breadboard.

Designing the 3D Prints

APAM Dimensions.jpg
Sensor Housing Dimensioned.jpg
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Avionics Bay Dimensioned.jpg
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The avionics bay is a combination of electronics, sensors, and three 3D printed housings. The electronics we discussed in Steps 5 and 6. The 3D printed parts consist of the A-PAM housing, the Payload Sensor housing, and the Payload Adapter base. They are combined together and fit inside the clear payload bay of the Olympus rocket.

Both of the housings and the payload base were designed using Tinkercad (https://www.tinkercad.com/things/iY6COkklnYd). The designs are based on the original A-PAM drawings which are designed around the inner diameter of the BT60 body tube (40.5mm). The Olympus has a slightly larger interior diameter (44mm). To allow the original A-PAM to fit snugly inside the Olympus payload bay, the front and rear rings on the A-PAM were simply increased in size to accommodate the larger tube.

A-PAM Housing

The housing for the A-PAM components is designed to hold all four modules and it fits snugly into a BT-60 body tube. Since the Olympus is slight larger than a standard BT-60 tube (41.6 mm versus 44 mm), the top and base of the A-PAM housing is increased in diameter to make up the extra space.

Looking at the A-PAM we can see that the top bulkhead of the bay includes:

  1. Openings for the USB connection on the Nano.
  2. Directly underneath the Nano is the microSD card module. Like the Nano it too has a slot to allow you to insert and remove a microSD card.
  3. At the bottom is the LiPo battery holder with a rectangular opening that allows both the power plug and charging cord to exit the housing.
  4. Off to the left side is the RGB LED status lamp, while the right side opening allows the Nano power plug to exit the housing. When the battery and Nano power plugs are connected it turns the system on and provides power to the entire avionics system. No need for a switch.

In designing the A-PAM I have provided openings in the housing wherever possible. The rails of the housing have multiple lightening holes. These can be used to route wiring if desired. For the basic module I am able to put the entire package together before inserting it into the housing.

The slots are deep enough to hold the Nano board, yet not obstruct the wiring holes down each side of the board. While the two boards and the LED are held in place by friction, the battery has the greatest potential to move about. You should consider securing the battery in place using glue or other adhesive. If you find that the boards or the LED are not tight enough and prone to movement, consider securing them in place with a bit of adhesive as well.

At the rear of the housing is a ring with two small holes on opposite sides of the ring. These holes are used to attach the sensor housing to the A-PAM. Use M2 nylon screws, washers and nuts to attach the sensor housing to the A-PAM housing.

Sensor Housing

The sensor housing only needs to hold two sensors; the BMP180 and the MPU6050. It needs to be able to attach to the A-PAM housing. That attachment is accomplished through the use of two M2 screws. The mount is designed to be open enough to allow any wiring to pass between the sensors and the A-PAM.

Start the design of the sensor payload housing by using the adapter ring. This is a copy of the ring that makes up the bottom of the A-PAM. By using this ring as the basis for our design, we can be assured that the sensor housing (or any payload housing you design) will line up and mate with the A-PAM housing. The Tinkercad drawing includes the adapter ring as a separate drawing.

The sensor housing consist of two rings separated by four posts equally spaced around the ring. Each ring has an offset mount that allows a sensor to be screwed into place. The offset allows the MPU6050 to be centered in the housing. Both the top and bottom rings have the offset and two mounting holes to simply make installing the sensors easier.

The sensors are held in place by M2.5 screws. A series of spacers are used to allow for the wiring to flow from the sensor housing into the A-PAM. As shown in the graphic. There are two 12mm spacers located between the mounting bracket and the MPU6050. Between the BMP180 and the MPU6050 is a 10mm spacer. Finally there is a 6mm spacer between the mounting bracket and the BMP180. Check the fit of your sensor boards along with the spacers prior to finalizing the design of the sensor housing. You may need to adjust the spacers or the housing to allow everything to fit properly.

Payload Base

The third and final part of the avionics bay is the payload base. It was quickly realized that the payload base that comes with the Olympus model would not work with the electronic payload that was being designed. The standard base did not allow for any method of securing the payload in the payload bay. This resulted in a new base being designed and printed.

The base is attached to the sensor housing and replaces the original plastic base that comes with the Olympus kit. The base is 3D printed and allows for the sensor housing to be screwed to the base. The payload base is designed to match up to the bottom ring of either the A-PAM or the sensor housing. The base also secures the clear payload section to the rocket.When all three pieces (the A-PAM, the Sensor Housing, and the Payload Base) are assembled together it makes up the complete Olympus avionics bay.

The Completed Avionics Bay

When the three sections (A-PAM, sensors and base) are stacked together they form the completed avionics bay. Housings are attached using M2 screws. This keeps the screws within the clear payload housing. The sensors are attached with M2.5 screws and spacers. The recessed area in the top of the payload base provide room for the screws heads.

The payload base doesn’t need the large surface area to hold the clear payload tube in place. This is because the sensor housing and the A-PAM housing all work together to secure the clear tube to the rocket.

The recovery system is attached to the payload base. As the base is part of the entire avionics stack, this helps ensure that the electronic payload section will stay attached to the parachute – even if it breaks away from the rest of the Olympus rocket.

3D Printing the Housings

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The stl files are exported individually from Tinkercad and imported in Cura. When printing these parts I used a 0.2mm layer height and 2-wall construction. Supports were necessary for the sensor housing and the A-PAM housing. Supports are optional on the base. Infill was set to 12% for all three parts.

Printing the Housings

Both housings and the payload base was printed on an End 3 V2 printer. I use PLA+ 1.75mm filament (stands up better to heat than plain PLA filament) and it has worked well for me. The A-PAM and Sensor housings were printed in a bright orange color for high visibility in case it separates from the rocket. The payload base was printed in silver to match the rocket’s color scheme

I did add four custom support cylinders to help bridge the gap in the A-PAM and Sensor housings. Each support tube was just 2mm in diameter. For me, this arrangement seemed to work slightly better than using just two 4mm supports on each side. We also used the support tubes on the payload base were the screw holes are located. As with most projects like this, you may wish to try both. Results can vary from printer to printer so use the settings that work best for you. The supports are removed once the print is complete.

Note: Since this project was completed, Cura has released an updated version that now includes tree supports. In some of our initial prints using the tree supports on the overhang sections of the prints they now seem to be much better in quality. This can be seen in the picture of a test print using the new tree supports option.

The Electronics Installation Process

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With the avionics and sensor housings printed, it is time to wire the components together. This takes some planning and patience as you are working in tight quarters. However, it is possible to get everything installed with a little room to spare.

The LED lamp requires four connections, while the microSD card module requires six (including a common ground with the LED and card module). The two sensors both require I2C connections and the BMP180 needs a 3.3 volt power supply. To complete the wiring is the VIN and ground connection coming from the battery to the Nano.

I was able to determine pretty quickly that soldering the wires to the top of the Nano was going to cause issues. Instead, the wires come up from the bottom and are soldered into place.

The next item that became readily apparent is that the components would need to be soldered in place first and then installed in the avionics bay. Trying to solder next to the plastic avionics bay was not going to end well.

Wiring the Components

There is no single method to installing the connections on the avionics package. You can do it in any order you think will work best for you. The order that I present here is just one method, but not the only method.

Installing the MicroSD Card Module

I gave considerable thought on how to attach the microSD card module to the Nano. The connections on the Nano are along the sides of the board, while the card module has pin connections that are at the rear of the board. While I did give some thought to removing the pins and soldering the wires directly to the board, in the end I decided to make use of the pins. The use of the pins seems to make the assembly a bit easier.

In the picture you can see five of the six microSD card module wires routed to the rear of the Nano (the others wires seen include the I2C connections, power and ground wires and the 3.3 volt connection for the BMP180).

Note: To help identify the 3.3 volt power line, it was marked with black stripes using a permanent marker.

The microSD card connection wires use a single six slot DuPont connector at the end. The wires are long enough to curl around and reach the pins of the card module.

The picture shows the card module wires inserted into the six slot DuPont connector. The other end of the wires are soldered to the underside of the Nano and exit to the rear.

Before you install the Nano board into the avionics housing, you must complete all of the soldering connections.

Installing the Sensor Package

The two sensors share three common connections; SCL, SDA and Ground. This made the soldering of the three components a bit easier.

I started by soldering the 5 volt power supply on the MPU6050. Next I solder the ground wire, but I made the ground wire long enough to extend from the MPU6050 to the BMP180. I did the same thing with the SCL and SDA wires. This finished up the MPU6050.

The next step is to solder the connections to the BMP180. First I solder the 3.3 volt power supply (this is the red wire with the black stripes). Next I attached the 10mm spacer that connects the BMP180 to the MPU6050. I had three bare wires that would be going from the BMP180 to the MPU6050. I used small sections of heat shrink tubing to protect these wires. Attach the BMP180 to the spacer using a screw. Make sure to thread the correct wires through the appropriate pins on the BMP180. The two sensors end up with the connections directly in line with each other. I now had three wires through the pins on the BMP180 that I could solder in place. Afterwards the excess wire was trimmed off. With the sensors soldered together they are mounted in the sensor housing.

The next step was to solder the sensor wires to the Nano. As with the microSD card module, this is done before the Nano is installed in the housing. The picture shows the sensors and sensor housing, with the wired connections going to the Nano. You should allow some extra wire to give both parts the ability to move while being assembled. However, too much excess wire will make the assembly much harder than it should be.

Installing the LED Status Lamp

The last component to install is the LED status lamp. Fortunately, all of the pins used for the lamp are on the same side of the Nano board and pretty close together. Unfortunately the lamp is located on the side between the two plastic mounting rails for the Nano and the microSD card. This does not leave much working room.

I knew early on that I wouldn’t be using any extra wire for these connections. Except for the wire that connects to the common ground, this is true. The first thing I do is solder the 220Ω resistors to each of the red, blue and green pins on the LED. I cut the pins on the LED short, as I knew there was a limited amount of space to work with. I also want the wires from the resistors to fold back to reach the connections on the Nano. The picture shows this part of the assembly. The resistors are soldered in place and the wires are bent into the approximate position on the Nano. The ground wire has not been soldered into place at this point.

With the Nano board inserted into the avionics bay, the board comes all the way to the forward bulkhead. I knew that the lip around the LED lamp would end at the bulkhead as well. I could line up the LED lip with the end of the Nano board and then route the resistor wires to the appropriate connections on the Nano. However, at this stage I was not ready to solder these wires in place. I need to make sure the assembly will fit inside the avionics bay.

Carefully insert the Nano and LED assembly into the avionics bay. With both pieces in their proper position, the resistor wires are bent over to hold them in place. Both pieces are carefully removed and the wires soldered in place.

In the pictures you can see the other connections are already in place. With the clamps holding everything in place I can solder the status lamp to the Nano and then trim off the excess wire.

Before you move on to the final assembly, check your system to make sure everything is working as expected. It is important to test your components and assemblies as you go along. It makes it much easier to detect and troubleshoot issues when they occur.

Final Assembly

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With everything soldered in place, it is time to start the final assembly of the avionics bay.

The Battery

The first component to be installed is the battery. The battery has two sets of wires coming from it. The charging cable has a 3-pin connector and is attached to the shorter wire set, while the power cable has a 2-pin connector but contains the longer set of wires.

When inserting the battery, both connectors will not fit through the opening at the same time. Begin by inserting the charging cable and make sure it is completely through the opening.

Next insert the power cable through the opening. Once both cables and connectors are through the opening, push the battery forward into the avionics bay.

Nano & microSD Card Module Placement

Next connect the microSD card module to the Nano. With the two connected, begin to insert the entire assembly into the A-PAM housing. The sensor housing is to the rear as the cable lengths allow it to move out of the way while working on the A-PAM components. You can also see the battery cables are extended fully through the front of the housing.

Continue to move the Nano and the microSD card module forward until the USB connection of the Nano is completely within the opening. The front of the microSD board should be flush against the inside of the forward bulkhead. The LED status lamp should slide into position along with the Nano. When moving this assembly take your time, making sure the LED lamp and the Nano both move forward at the same time.

Attaching the Sensor Housing

With all of the components secured in the A-PAM housing, it is time to attach the sensor package. The picture shows the two components being lined up. You will need to work the wires into the sensor housing as you bring the two housing together. Once lined up insert two screws to secure the two housing together.

Attach the Payload Adapter

The final part that needs to be attached is the Payload Adapter. There are two screws that attach it to sensor housing. Make sure that these screws are secure, as this is what attaches the entire payload assembly to the recovery system. The picture shows the completed assembly.

This completes the assembly of the avionics package for the Olympus Project.

Building the Rocket

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Building the Olympus Payload Model - Part 1 "Inside the Kit"
Finishing the Olympus Payload Model - Part 1 "Filling the Fins"

The Olympus model rocket kit was mostly built according to the instructions, with some minor modifications. The rubber band shock cord that is included in the kit was replaced with 1/4-inch wide elastic band. This can be found in any sewing section of a big box store. I also replaced the base of the payload section with a 3D printed base that is incorporated into the payload housing.

Prior to paint the seams on the body tube were filled with thinned wood filler. This same wood filler was used to fill in the grain of the balsa wood fins. The model was primed using Rustoleum Filler-Primer. This is typically found in the automotive section of a big box store, where body repair materials are sold. The model was wet sanded to a smooth prior in preparation for the color

Selecting a Color Scheme

There is a YouTube channel I frequent called “Max’s Models” (https://www.youtube.com/@maxsmodels). The channel motto is “Make it what You want it to be” and that is exactly what I decided to do. The model is not painted as depicted on the kit’s cover card. I was building this rocket as a test platform for an Arduino electronic payload. To me, this was like a smaller version of the sounding rockets that are used to test much larger and more powerful electronic payloads. I wanted this Olympus to look like a sounding rocket.

I decided to base the color scheme on the very distinctive Canadian Black Brant III. This color scheme consist of a red body tube with a white stripe along with a single white fin. The nose cone and payload bay is painted silver. I planned on making my Olympus look similar.

Decals and Trim

The decals I used in this kit came from spares I had in my scrap decal box. Again, this isn’t a scale model, so you can use whatever you want.

The other part of the trim is stick-on vinyl. This is the same vinyl that folks use in their Cricut machines. I used two strips of silver vinyl at the top and bottom on the clear payload bay. This helps hide the shoulders of the nose cone and the payload adapter. I also added two vinyl black boxes at the top of the body tube, similar to the Black Brant.

The last change to the model included the 3D printing of the motor retaining ring in black plastic, to replace the kit’s gray ring. It just looks better.

This completes the build of the Olympus model. I was very pleased with how the model turned out. I really prefer the red and white color scheme I chose over the white and copper color scheme on the kit face card.

Using the Olympus Electronic Payload

When you are ready to use your altimeter in an Olympus flight, the following steps are recommended. You can use this as a baseline for developing your own checklists for all four stages of the flight.

Preflight

  1. Determine which microSD card will be used for flight. It is recommended that a blank card be used and that you format the card prior to use. Place it into a computer to check for errors.
  2. You may wish to rename the card to something that make sense for the mission. This may include a flight date, project name, session number, etc.
  3. Charge the battery. This will help ensure that you have plenty of battery power should you find your rocket and payload sitting on the pad for an extended period of time.
  4. Do a preflight test on the payload. Insert a microSD card and turn on the system. Move the payload bay around and then turn the system off. Remove the card and insert it into a computer and read the data. This will help ensure everything is working properly before heading to the pad.
  5. Place clear payload bay over the electronic payload. Secure to payload base using tape. Do not cover vent holes located near bottom of the payload bay.


At the Launch Pad

  1. Insert the flight ready microSD card into the payload bay.
  2. Connect the two battery clips to power on the system. The status lamp should turn green to indicate the system is functioning as expected. If you get a color other than green, it indicates an error in the system. Error messages include:
  3. Flashing Red – microSD Card Module error. Check that a card has been inserted into the holder. If a card is present remove and reinsert. If you still get a flashing red lamp, try a different card. If still getting a flashing red lamp, check for loose connections
  4. Flashing Yellow – MPU6050 error. Check for loose connections
  5. Flashing Blue – BMP180 error. Check for loose connections
  6. Steady Blue – File Write error. This indicates that there was an issue while attempting to write data to the microSD card. This error will attempt to self-correct by resetting the microSD card module. If it does not reset, check the microSD card and replace if necessary.
  7. If payload appears to be working properly, attach nose cone to payload bay and secure with tape.


During Flight

  1. Observe the flight of the rocket so that it can be recovered successfully
  2. You may want to use multiple observers. If the payload bay were to separate from the rocket one observer can track the payload bay while the second observer tracks the rocket.
  3. Track payload bay to landing site. Upon arriving on the landing site, remove the tape from the nose cone and remove the nose cone from the payload bay.
  4. Disconnect the battery from the payload to turn off the payload
  5. Observe the overall condition of the payload. It anything appears missing, you may want to search the local area.


Post Flight

Upon returning to the flight preparation area

  1. Remove the payload bay tubing from the payload
  2. Remove the microSD card from the payload.
  3. Insert the microSD card into a computer. Confirm that there are data files on the card. Copy data files from microSD card onto the local computer
  4. During the appropriate time, perform analysis on the data collected
  5. Check the rocket and payload. Make note of any damage or missing components. Depending on any damage that has occurred, make a determination
  6. on whether it is safe to continue flying in the current condition
  7. to repair the rocket on site and attempt to fly again
  8. if the rocket will need extensive repairs offsite in order to fly again
  9. if the rocket has sustained major damage and is no longer in a repairable condition
  10. Make any notes and observations that may be appropriate for the mission/project.

Final Thoughts

This completes Project: Olympus. This was quite an involved project and I hope that you have enjoyed this project build.

Any time you create a project you should always go back and see how it might be improved. Such “lessons learned” will help you improve projects that you create later. It can also be beneficial to try some of the ideas on a different project. Improvement through iteration is a valid engineering process. Companies like SpaceX have made great strides in rocket performance by trying new things, and being willing to break stuff to learn in the process. Use your imagination and think of what you would like to do – what you want to accomplish. Then set out to do it!

NAR Logo.jpg

If you enjoy model rocketry and projects such as Project: Olympus, then consider joining the National Association of Rocketry (NAR). The NAR is all about having fun and learning more with and about model rockets. It is the oldest and largest sport rocketry organization in the world. Since 1957, over 80,000 serious sport rocket modelers have joined the NAR to take advantage of the fun and excitement of organized rocketry.

The NAR is your gateway to rocket launches, clubs, contests, and more. Members receive the bi-monthly magazine "Sport Rocketry" and the digital NAR Member Guidebook—a 290 page how-to book on all aspects of rocketry. Members are granted access to the “Member Resources” website which includes NAR technical reports, high-power certification, and more. Finally each member of the NAR is cover by $5 million rocket flight liability insurance.

For more information, visit their web site at https://www.nar.org/