smoovy motor applications

Our objective is to master the hardware and software development of miniature mechatronic device and develop small devices heading toward useful applications, including as much autonomy and "intelligence" the most recent technologies allows for at reasonable costs.

A 1cc mobile robot


This robot has been built by André Guignard and programmed by Olivier Matthey.

It uses two smoovy 3mm motors from RMB. A first gear transmits the movement to the wheels, made of the second gear level. The initial design was using a rubber caterpillar, but its efficiency was too weak. The robot does not fit any more into one cubic centimeter. We have to find better ideas for the next generation.

A PIC 16C54 drives directly the motors. Two photo-transistors and one LED have been bonded on the side in order to follow a wall. This is not yet operating well; the ambiant light is too strong compared to the LED power.

A beautiful demonstrator - it includes ten RMB bearings


The wings of a beautiful Morpho from Central America are powered by a smoovy 3mm motor. No hope to make the Butterfly fly, just move the wings up and down.

In order to have the the body as small as possible, and avoid several levels of gears, a wormscrew is used. The linear movement is converted into wing oscillations by a helical tape, beautifully built by André Guignard, allowing for a 90 degrees movement. You may count 10 ball bearings in this demonstrator. All standard products by RMB. One in the motor, one at the end of the lead screw, four for the wing hinges, four for minimizing the friction on the helical tape.

A PIC 16C54 is used. The software is trivial: the end switches are tested while the motor spin in one direction. There is anyway a change of direction after 50 turns. This was smart, because the end switches are too strong for the motor (0.1 by 0.5 mm CU).


A servo for miniature flying model


We are working on a servo using the Smoovy 3mm. The design is very simple. The casing is molded in Araldite. The motor and the wormgear are pushed in the slots. The PC board with the PIC 16C54 processor closes the box. For a weight of 1.5 g (including the PC board and processor), we get a push/pull force of 15 grams, with a very primitive software. The stroke is 8.5 mm, and takes 1 second (to be easily improved from the specs of the motor).

We do not know yet if end switches will be required for reliabilty. The design allows to put a sliding contact over a resistive coating. It is just a question of developing it: with such a size, it is not so easy.


We cordially thank RMB Bienne for their kind and efficient support and providing the smoovy motors and the ball bearings.

Name of this file: http://diwww/w3lami/mirobots/smoovy.html | Last modified by JDN 7.6.97 26.8.97

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