Motor

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biomorphic symbols for:
1. a DC motor
2. a Servo motor and for the :
3. Adaptive Bicore, Biomech Motor Controller (ABCore)

An actuator that converts electrical energy into rotational mechanical energy.

[edit] Overview

A BEAM bot will likely need motors' of some kind to make it move. You'll be looking at one of three different kinds, depending on your needs.

DC Motors -- this is your basic, run of the mill, small DC motor. Well, maybe not so basic -- it needs to be very efficient for BEAM usage.

Gear Motors -- this is essentially a small DC motor, with an attached gear train (to reduce output shaft speed, and increase output torque). For BEAM usage, you should be shooting for something on the order of 30 RPM.

Servo Motor -- this is a small DC gear motor with an integral position feedback pot and control circuitry.

Stepper Motors -- this is a bit more complex to drive than a DC motor, requiring pulse trains to move it, but in return gives you very good control over motor motion.

Most motors need motor drivers in most robots.

[edit] Hints

Bangalalorerobotics wrote:

There are n number of motors on the open market...NOW! Earlier BEAM stuff was made with "any motor that works here" principle. Looking over the tons of BEAM material around the internet, one cannot stop and feel that theres very little details of the motors used. This lack of details has made thousands of newbies jumping onto the BEAM bandwagon, thinking that it is "simple" to make these things work.

My advise , on several Forums, that it is NOT a begginers choice has fallen on deaf ears.

After many failures, one concludes that the Motors are something special - not all [motor]]s work.

The only motors that can work for BEAM are these:

Low Voltage, Low current motors:-

1.5V to 5Vdc motors
Motor current = 10ma to 50ma. These will be called ' high efficiency' motors by the concerned manufacturers. Also, Small motors mean less current. ( not anymore, cause there are small motors weighing <100gms @ 3KW !!)
Old Pager motors. ( old motors, not new. The newer "pager motor" is just the name. They hog a lot of current that a 3906/pn2222 bridge can never deliver.
Rated current on the sellers website is NOT a true story. The Motor current has a different value and meaning and varies wrt:
1. Voltage
2. Load
3. Duty cycle ( ...how many ON mins/hr...!!)
4. Manufacturer
5. Its design purpose ( things labeled TOY motors are best left alone)
6. Cost
7. "looks"

Lets realise one thing- BEAM was developed by Tilden, Wilf and others using easily available motors ( I guess junk / surplus/ canniballised etc.,). The antecedents of these motors may not be known to the user at all. Its is just that some motor worked and others did not.

This is the reason for the unending controversies of BEAM principle, where people never accept the working of BEAM circuits, even when they SEE the thing crawl around !!

There is a lot more electronics involved than the average newbie student/engineer/technologist can exhibit. You need to KNOW the difference between LS C AC HC HCT....( cynically, I have left out 'Hobbyist' since they are the guys with the grit and the elbow-grease. They never give up till they raise a junk-pile and get the thing working )

These are (some of) the reasons that pure BEAM is dwindling slowly and fast giving rise to L298/Microcontroller/FPGA/ controlled BEAM robots.