IOIO-2025: Task-3 (Penrose Punch)

Penrose Punch

Designed by Alphonsus Rouis (Philippines)

Difficulty: *****_ _ _ _ _

Paper size: 30 cm

Paper: 30-40 g/m²

Round: 1

A4 kağıdından çok rahat katlanıyor

Quick question - did people cut the pentagon following the instructions? Or cut a pentagon using other methods?

Asking as the instructions on page 15 does not look like leading to a regular pentagon...?

@Xinyi Xu :

Quick question - did people cut the pentagon following the instructions? Or cut a pentagon using other methods?

Asking as the instructions on page 15 does not look like leading to a regular pentagon...?

I followed the instructions and it felt like a regular pentagon to me, was good enough for the model. But I′ve seen people say it′s not really precise

@Florian VIDEAU :

I followed the instructions and it felt like a regular pentagon to me, was good enough for the model. But I′ve seen people say it′s not really precise

Thanks for replying! Re-checking the instructions, I realised that I missed the step to turn the paper over between 2 and 3 when taking reference lines, hence got the resulting lines far from pentagon...

@Xinyi Xu :

I realised that I missed the step to turn the paper over between 2 and 3

Yeah I made the same mistake, the result is irregular, corrected on 2nd try. I think if we follow the instructions the pentagon is both mathematically ideal and optimal to fit into a square.

Bence At gibi

Kolay oldu.

My favorite model of round 1.

I had great fun shaping this model!

Definitely my favorite model too