Chantel Anderson, 43, had the weapon under the seat of her friends car, which she was using to move her belongings to a new house.
Police searched the car and found the weapon under the front seat on January 13.
In cross-examination, Anderson said she had done Martial Arts for at least 25 years, after being taught in her downtime when working on fishing boats.
Anderson trained in Escrima Filipino martial arts, which uses knives and sticks. She said she liked to stay fit and was currently studying to become a personal trainer.
Anderson used nunchucks to strengthen her shoulders, which had ligament damage from horse racing.
She described the weapon as "short-chain nunchucks", which means they can only be used in front of the body.
She said she purchased them from Coinsave on Gloucester St for $10. They were "low quality" and "disposable".
Sergeant Simon Keith, questioning Anderson, did not see a reason for her to use the nunchucks for fitness, when they were not required for the martial arts she was training in.
Anderson said she forgot the nunchucks were in the car, because she was moving house and there were many personal items throughout the car. She said the nunchucks could have been pushed under the seat by a passenger in the car and she was not trying to hide them.
Judge Mark Callaghan dismissed the charges on the grounds police had not proved beyond reasonable doubt, that Anderson was using them for something other than fitness.
At the end of the court appearance, Anderson could apply to get the nunchucks back from the police.