Hydra, A Recipe for Innovation

According to Greek mythology, Hydra was a water monster with nine heads. Eight of these heads were mortal and the ninth immortal. Heracles (Roman = Hercules) was sent by Eurystheus to kill the Hydra. Every time Heracles cut off one of the serpent’s heads with his mace, however, the Hydra would regrow two new.

Even though the story is most likely just that, a story, it can serve perfectly to visualize a basic principle which can be employed to have more ideas and be more innovative.

The head symbolizes a thought process or an idea. You, the innovative mind, are Herakles and the mace represents some sort of activity.

An activity can mean writing it down, sketching the idea or creating a prototype, etc. So some form of doing or taking action. It can also mean to delegate the task of exploring an opportunity, work with a university (Capstone, Ph.D., etc) or discussing it with a team of open-minded colleagues.

Every time you take action, you allow your mind to let go of a thought it otherwise would try to process and view from different angles.

You can use Hydra to increase the flow of ideas in all situations from business ideas to vacation ideas. Because you just need a blank notebook to get started, you can do it everywhere, no matter whether you have a power supply or not.

The core of Hydra can also be found in other techniques, such as brainstorming. It can be used in slow-motion multitasking.

Practical Tip 1 – Be Prepared to Document

Keep a nice notebook (paper) and a pencil next to your bed to make a note whenever the muse visits. Don’t do it on loose sheets of paper. It doesn’t have the same effect and it gets messy fast. Leave space when you start with an idea by using the right sides only for example and write down dates whenever you add info.

Enterprises should provide online space where employees can propose ideas and collaborate with others (enterprise idea management platform). Employees throughout the company can join a project, not just a specific group.

You will see that over time the book with your ideas will get very full. You will go back to ideas you had years before and supplement them over time. I started with my books 9 years ago and got several hundred potential business and startup ideas.

It also happens from time to time that you see ideas you had in your book appear as actual products. Don’t worry about it, but take it as an “It can’t be too wrong what I’m thinking if some of the greatest minds have the same idea.” Try to learn from these occurrences how the innovator brought the topic to life.

Practical Tip 2 – Provide Environment

As an enterprise, plan some money for domain experts to provide a platform for further ideation (afterburner) of topics added to the enterprise idea management platform.

Allow departments to easily fund employee projects. Introduce an innovation currency (1 coin per person) for every employee which can be spent independently.

This fixes that some topics never get fixed due to the profit/loss responsibility of internally competing departments.

Practical Tip 3 – Learn to Sketch

Learn how to sketch. It is easier to add a small sketch to an idea than to describe it, especially when you want to communicate your idea in order to gain support for example in a management review presentation.

Practical Tip 4 – Provide Resources

Make room for innovation. If you are a company, I would highly encourage you to make room for your employees to explore better ways.

Give free access to equipment in their spare time such as servers, spectrum analyzers, motors, CNC machines, lathes or whatever you’re working with.

If employees have a good idea, encourage them, connect them with resources and give credit. Treat their ideas with respect and at an appropriate time, act as a sponsor / financial angel.

Practical Tip 5 – Rapid Prototyping

Automation and fast turn around is key. If you’ve left the initial stage (sketching, enriching) of the idea, being fast to iterate is key.

In the hardware world, this means rapid prototyping with 3D printing, 3D scanning, the use of a desktop CNC router, etc.

For software try either low code platforms or ecosystems with plenty of libraries and automate as much as possible.

Try to focus on “delivering” full cut-troughs through the stack to allow potential customers to test your product. This is where you should do hypothesis-driven testing at the latest. I prefer to already start it at the beginning.

Slow-Motion Multitasking

Highly creative people often have one thing in common and I’m glad we now have a name for it: slow-motion multitasking.

Texting while driving is a bad idea, we can agree on this. But for a specific kind of activity, doing multiple things at the same time is exactly what we should do.

Science has shown that multitasking on a per-second basis, also known as human multitasking, is decreasing productivity.

But I’d like to argue that developing multiple ideas at the same time is something completely different. This means you should move back and forth between ideas, depending on where you can contribute to the success, not where you have to work due to an artificial schedule.

But please, this procrastination/piling up of initial ideas should not be confused with firefighting, also often observed when people work on different topics at the same time. It should also not be used as an excuse not to work on a difficult topic.

If you just had a brilliant idea for another topic, it is beneficial to set one thing aside for some time. Switching allows the brain to visualize a problem by taking new impressions and learnings into account.

I observed working on projects of different domains at the same time works best for me. For example, defining the architecture for industrial, real-time analytics, high-throughput streaming application and building (design, manufacturing) an endurance drone.

This can be perfectly combined with open innovation and Hydra.

Practical Tip 1 – Be Prepared to Document

Keep a nice notebook (paper) and a pencil next to your bed to make a note whenever the muse visits. Don’t do it on loose sheets of paper. It doesn’t have the same effect and it gets messy fast. Leave space when you start with an idea by using the right sides only for example and write down dates whenever you add info.

Enterprises should provide online space where employees can propose ideas and collaborate with others (enterprise idea management platform). Employees throughout the company can join a project, not just a specific group.

You will see that over time the book with your ideas will get very full. You will go back to ideas you had years before and supplement them over time. I started with my books 9 years ago and got several hundred potential business and startup ideas.

It also happens from time to time that you see ideas you had in your book appear as actual products. Don’t worry about it, but take it as an “It can’t be too wrong what I’m thinking if some of the greatest minds have the same idea.” Try to learn from these occurrences how the innovator brought the topic to life.

Practical Tip 2 – Provide Environment

As an enterprise, plan some money for domain experts to provide a platform for further ideation (afterburner) of topics added to the enterprise idea management platform.

Allow departments to easily fund employee projects. Introduce an innovation currency (1 coin per person) for every employee which can be spent independently.

This fixes that some topics never get fixed due to the profit/loss responsibility of internally competing departments.

Practical Tip 3 – Learn to Sketch

Learn how to sketch. It is easier to add a small sketch to an idea than to describe it, especially when you want to communicate your idea in order to gain support for example in a management review presentation.

Practical Tip 4 – Provide Resources

Make room for innovation. If you are a company, I would highly encourage you to make room for your employees to explore better ways.

Give free access to equipment in their spare time such as servers, spectrum analyzers, motors, CNC machines, lathes or whatever you’re working with.

If employees have a good idea, encourage them, connect them with resources and give credit. Treat their ideas with respect and at an appropriate time, act as a sponsor / financial angel.

Practical Tip 5 – Rapid Prototyping

Automation and fast turn around is key. If you’ve left the initial stage (sketching, enriching) of the idea, being fast to iterate is key.

In the hardware world, this means rapid prototyping with 3D printing, 3D scanning, the use of a desktop CNC router, etc.

For software try either low code platforms or ecosystems with plenty of libraries and automate as much as possible.

Try to focus on “delivering” full cut-troughs through the stack to allow potential customers to test your product. This is where you should do hypothesis-driven testing at the latest. I prefer to already start it at the beginning.

Rugged Carry-On Drone Case

Carrying or even checking drones on an airplane exposes the fragile mechanics to all sorts of opportunities to break. If the frame has been designed in a CAD program such as Fusion 360, it is very easy to create a decent rugged drone case tough.

Just project the outline and connect the corner points with a spline.

Then extrude the outlines of components such as the FPV camera, the gimbal rails etc at the right height.

The waterproof case has the right size to be taken on a plane as carry-on and allows to create additional layers to fit all required equipment. Please find the PDF version here: Quadcopter Case Foam.

Two Acoustic Panels, cut to length perfectly fit the top rugged drone case to protect the props.

Even though there are specific foam cutter available,  Kaizen Foam can be perfectly cut with a 1/4″ flat end mill on the Shapeoko or other routers at 1524 mm/min.

Watch out for:

  • Adaptive clearing of large pockets needs quite some babysitting though as the foam tends to wrap around the end mill.
  • Kaizen foam layers are around 5mm high. Try to avoid pockets to heights which would result in too little material left till the next layer
  • Align pockets with the height of the Kaizen foam (recommended 30mm)

6S LiPo Battery Value and Capacity Comparison

Flight time depends mainly on the drone weight. In order to get flight times above 1 hour on a single charge (as shown here), the weight has to be minimized. Typically the most dominant weight hereby is the battery. To identify the best battery I created a 6S LiPo Battery Value and Capacity Comparison.

While there are several arguments speaking for 6S, for me the primary point is added agility to the PhoDrone build. This fixed the issue of sporadically maxing out motors.

Even though the 12000mAh battery shows the best value and density, its 266Wh are too high for taking it on an airplane as carry-on (FAA limit is 100Wh / battery, with airline approval two batteries up to 160Wh). Due to this reason the 6600mAh (147Wh) has been selected. According to the Frontier airline hotline there is no upfront approval required.

  • Value is calculated by Capacity / Price)
  • Density is calculated by Capacity / Weight

The diagram above is sorted left to right by Ranking = Cap /Weight * Cap /Price

See also 4S LiPo Battery Value and Capacity Comparison.

Small Batch Prototyping for 3D Printed Parts

3D printing enables rapid prototyping but lacks production-ready qualities such as smooth surfaces, temperature resistance and food safety. These attributes however can easily be added by combining 3D printing with casting silicone and urethane plastic for small batch production runs.

As long as you don’t need hundret thounsands of parts, this method should get you up and running without paying a fortune for a silicone injection molding setup.

When selecting mold making materials for 3D printed parts, it is important to be clear about the intended material for mold and cast .

Some points to consider are:

  • Silicone such as Dragon Skin can be extremely difficult to stick to surfaces, except silicone itself. 
  • Urethane plastic such as Smooth Cast 310  is exotherm. This means it gets hot while it’s hardening.
  • Some 3D printing filaments are more temperature-sensitive than others.
  • Some 3D printing filaments are easier to post-process than others.

Having this in mind, the proper materials can be chosen basing on the desired material of the positive.

For PLA the following works nicely:

Final Positive Mold Seperate Seal Release
Smooth Cast 310 Dragon Skin 30 Monster Clay XTC-3D Ease Release 200 
Dragon Skin 30 Smooth Cast 310 Sculptex oil based clay  XTC-3D Universal Mold Release

Please note that urethane plastic is exotherm:

  • This requires a non-wax based clay to define the two-part mold. Otherwise the surface in contact with the clay will be full of air bubbles due to the melting wax-based clay.
  • Hot glue is not a good choice for the mold as the glue melts again and the mold leaks. Better use glue + Acryl or Wood + Screws (+ glue)

Applying multiple coats of XTC-3D with sanding (400…1500) in between is highly recommended.

Degasing the silicone and urethane before pouring significantly reduces trapped air bubbles and increases the chance of success.

Other useful items:

 

Amount Description Link
1 Medicine Cups to mix XTC-3D Amazon
1 Gloves Amazon
1 Mixing Cups for silicone and urethane plastic Amazon
1 Craft Sticks Amazon
1 Safety Glasses Amazon
1 Vacuum Chamber for degasing Amazon
1 Vacuum Pump for degasing Amazon
1 Clay Sculpting Tools Amazon
1 Hot Glue Gun Amazon
1 Durometer Amazon

Raspberry Pi Zero W Enclosure

The 3D model of the Raspberry Pi Zero W is hosted on Thingiverse. This page contains the bill of material, in case you want to build a similar setup.

This setup in combination with a regular 3B has been used for demonstrating “Real-Time” FFT of ADXL345 data via MQTT with Node-Red. The code and documentation can be found on Github.

Bill of Material

AmountDescription
1 Raspberry PI Zero W
1 Memory Card
1 Power supply
1 HDMI Adapter (optional but highly recommended)

Long Flight Time (1h), Aerial Photography Quad, 770mm 17inch

RC Groups

Centerboard

The center board has been glued with HK CA glue (HC-50-175). A small frame with screws through the four beam holder holes kept the sandwich layers aligned.
Note: Better do large areas with this glue outside as it generates a fume.
Using nylon spacers and screws, the top and bottom sandwich were assembled.

Beams

The beams were machined with a 1/32″ flat end mill and cut to length in the last run.
M3 nylon screws lock the beams and act as breaking point when crashing.

Electronics

To attach the electronics to the center board, I chose two different approaches. Components which will not be used in every flight have been attached using Velcro. The other components were glued directly to capton tape I put to the center board. The ESCs were wrapped in capton tape to prevent short circuits. I hope the heat dissipation is reasonably low with the 30A ESCs.

Sandwich Glue

  • HK CA glue (HC-50-175)
  • Loctite Vinyl, Fabric & Plastic Flexible Adhesive
  • HK 30min Slow Cure Epoxy
  • 3M General Purpose 45 Spray Adhesive

Sandwich Bend Test

  • 100x10mm x 1mm CFK, 3mm Fill, 1mm CFK

CFK 1mm, 3k plain weave carbon, orientation parallel (0°/90°) to centerline
Fill +/-45°

Bend test showed best adhesion and no separation up to 6kg for HK CA glue (HC-50-175). All other separated well below this (usually at around 3-4kg). However glueing is tricky for large areas such as the center board.

Endurance

During the first flights, the flight time was reasonably high at a bit over one hour with 1555 props.

Crashing

Arms folded away during the first crash (I’d love to call it unplanned rapid decent though :-)) and the M3 nylon screws broke as planned, preventing damages to the rest of the drone.

Flight Time

With this setup, flight times above one hour have been achieved, even including the 180g 3-axis gimbal and GoPro.

In the diagram below various test flights for a 15″ 5.5 and 17″ 6.0 propeller were aggregated to show the effect the prop choice has on flight time.

Update: I’ve updated the battery with a 6600mAh 6S and the quad flies a lot more stable now.

Previously the flight recorder showed motors occasionally maxing out during sharp moves or wind gusts.

I’ll do some test flights and check the flight time. First flight was 2500mAh for 15min

Bill of Material

Amount Description Link
6
rctimer 5010 360kv
NA
3
Multistar Lipo Pack XT90
Amazon
4
Flyduino KISS
Amazon
4
1760 Folding Props
Ebay
1
Flight Controller and Power Module
Hobbyking
1
GPS witd Compass
Amazon
1
Receiver
Amazon
1
Damping Balls
NA
1
Folding GPS Antenna Base/Black
Ebay
1
Lipo Voltage Checker
Amazon
1
FPV Camera
Amazon
1
VTX
Amazon
1
Telemetry Radio
Amazon
1
Skyfpv Video Switch
NA
1
OSD
Amazon
2
LC Filter
Amazon
1
FPV 3 Axis CNC Metal Brushless Gimbal With Controller For DJI Phantom GoPro 3 4
Banggood
1
GOPRO
Amazon
1
pigtail
Amazon
1
Silicone Wire
Amazon
1
FPV Antenna
Amazon
1
Transmitter
Amazon
1
Goggles
Amazon
2
Goggle Battery
Amazon

4S LiPo Battery Value and Capacity Comparison

Flight time depends mainly on the drone weight. In order to get flight times above 1 hour on a single charge (as shown here), the weight has to be minimized. Typically the most dominant weight hereby is the battery. To identify the best battery I created a 4S LiPo Battery Value and Capacity Comparison.

  • Value can be calculated by Capacity / Price)
  • Density can be calculated by Capacity / Weight

The diagram above is sorted left to right by Ranking = Cap /Weight * Cap /Price

See also 6S LiPo Battery Value and Capacity Comparison.