So far we haven't addressed the key question - any good reasons why it won't work?!!After all, you can easily arrange a wheeled trolley to carry the large bank of accumulators, a back support is readily available from any good surgical appliance shop, and humming motors can easily be taught the words...
The main objection, as I see it, is the poor performer would have nothing on which to blame a lapse of concentration - unless the thing went wild and started making up its own tunes - now there's a thought!
Glad we could rely on Dave to come up with a sensible thread for a change!!
;o)