After the prototype was finished we can make the following remarks:

• The design of the alminium part and the ergonomic grip is quit good: both the shape and the dimensions
• The box that containts all the electronics and, the servomotor, spring, etc. is of poor strength and poorly executed. Also it was diificult to mount everything with the box as it is. Taking in consideration these remarks one might think of making the box out of Alminuim our plastic (using the 3D printer).
• We should have talking all the electronic wiring in consideration before building the prototype. Now the wires are likely to interfere with the mechanical parts resulting in irreversible damage.
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