During the concept generation process it can be difficult to come up with initial design ideas at the beginning of the project as you may not have all the required information available. In some cases with the requirements you are given can restrict your thoughts and hinder you from achieving your project goals. Thankfully there are multiple tools at hand to help you tackle these issues at the early stages of your project. We will showcase two of them which are the Ideal Final Result and Reverse planning.

Ideal Final Result

Ideal Final Result (IFR) is a tool that describes the best solution and ignores any contradictions or drawbacks of the design (1) which will help unlock the designer to come up with concepts or ideas to solve an issue.

Ideal Final Result for a 2p Pocketqube satellite

As mentioned in our TRIZ example we will use IFR to come up with ideas for our 2p pocketqube (PQ) satellite which will only send a beacon. Our 2p PQ will have the following functions:

• No more than 500g
• Withstand all loads from launch vehicle at NASA GEVS levels
• Cheap to be made
• ADCS accuracy of ±1°
• Has 10W power
• No thermal issues
• High download link and can be completely reprogrammable.
• 100% reliable.
• Every subsystem fits with enough spare for optical payload.

As we can see we will have multiple issues with this design will severe limitations and contradictions however we now have a concept we could work on and make it more realistic. Even starting with something completely unrealistic will allow you to begin with a project and it helps to clearly define what exactly you want to achieve.

Reverse Planning

The obvious drawback of IFR is that the result it comes up with ideas that are a complete fantasy and it would be impossible to develop a cheap 2p PQ that will fit all of the criteria also it is difficult to produce a practical solution to an idealistic idea. One tool that is used in TRIZ in developing a realistic solution from fantasy is reverse planning where you think of ways for your design to fail your requirements (2). This exercise can help prevent details being over looked which could cause failures in real life. The process does look similar to a FMEA but without the weightings and failure modes.

The first step is to list your requirements, standards and objectives of your design. Then you list out ways how you would fail those requirements. At the end you can then come up with solutions to avoid these issues. This is also useful for identifying potential issues with assembly, operation, disposal etc.

The table below is an example of reverse planning being used on the 2P PQ satellite. We have a template which you can use to begin your own reverse planning exercise.

Requirement	Reverse plan	How to achieve this result	Solution
Must not weigh more than 500g	Exceed mass limit	Use heavy materials such as steel for the frame	Use lightweight materials such as Aluminium or use the solar panels as part of the structure.
No thermal issues to prevent damage to electronics	Satellite body temperature exceeds safe limits for electronics	Avoid using thermal insulators.Place sensitive electronics to heat sources like baterries and radios.Have satellite generate excessive power for such small body	Apply shielding, thermal insulation or past to sensitive equipment   Keep sensitive equipment away from major heat sources   Have satellite only generate power that is required and apply radiators to remove excess heat
ADCS accuracy of ±1°	Accuracy is >±1°	Center of gravity (COG) is towards end of satellite.Poor tolerances in reaction wheels. Make reaction wheels from imprecise machining processes such as 3D printing to make them unbalanced. Make reaction wheel magnetic to interfere with magnetorquers.	Keep COG as close to the center of the satellite as possible.Use correct tolerances to locate wheels to motor.Use CNC turned machining with adequate runout to ensure wheel is balanced. Make wheels out of non ferrous materials such as aluminium or brass.

References

1. Ideal Final Result. Mycoted. [Online] [Cited: February 13, 2023.] https://www.mycoted.com/Ideal_Final_Result#:~:text=Ideal%20Final%20Result%20(IFR)%20is,TRIZ%2C%20a%20problem%20solving%20methodology..

2. Hipple, Jack. Creativity in reverse: a new way to use TRIZ. Innovation management . [Online] [Cited: February 14, 2023.] https://innovationmanagement.se/2006/02/28/creativity-in-reverse-a-new-way-to-use-triz/.