I have done >200 China orders (mostly aliexpress.com, sometimes banggood.com) in the last two years, mostly with free shipping. I ordered microcontrollers, motors, electronic components, ... and all (but two) arrived without issues at my home. They contained a stamp "freed from customs clearance" because they were too cheap.
Last week I got mail notification that one of my orders was restrained at Heidelberg custom office. They did not believe the value mentioned on the parcel (8$), and the size of the parcel got their attention. On the phone they explained that often plagiarising products are sent this way from China, and those are prohibited.
They were right with the value, the
caterpillar robot platform did cost 22.90$ (only), but that was less than the value where I would have to pay German VAT.
I should bring my bill with details and open the parcel in order to decide how to proceed.
On Friday morning I took train to Heidelberg, presented the detailed bill, opened the parcel, and had to pay nothing, but could just take the parcel home. Reason was it was no plagiarism, and below the VAT threshold, any VAT below 5€ will not be taken. In Germany we have 19% VAT, which means that any product cheaper than 25.31€ or 28.08$ does not need VAT to be paid.
So I went back home with train, adding 14.30$ train tickets to the 22.90$. I have many different robot platforms at home, but this was my first caterpillar one.
A first functional test without microprocessor with 4V turning on same location went well:
https://www.youtube.com/watch?v=9Ygm0Oxhf8c&feature=youtu.be
Today I did a second "straight" test, again with only 4V of a single 25C LiPo (motors can take 3-9V):
https://www.youtube.com/watch?v=yUcnWbPxAoE&feature=youtu.be
Counting the tiles and single steping youtube video time showed 1.05m/s with only 4V:
$ bc -lq
sqrt(9^2+1.25^2)*0.315/(38/14)
1.05449957813359675047
Hermann.