This is a short demo (link below) of The Thumb Bar Controller (U.S. Patent # 11,495,198) for electronic keyboards, to replace or compliment pitch/mod wheels & joysticks (that require a second hand) and pedals!) It is more expressive and precise for recording or performance. To watch the full demo and see all you can do, go to the other link below. I have a design for larger keyboards that connects only on the right side and does NOT interfere with left hand playing, It telescopes to the size of your upper keys zone.

If you play multiple keyboards, as I, you will appreciate this.

Pitch up & down are controlled by pushing the bar up for pitch up & down for pitch down.
Pushing the bar in controls modulation, and can be done independently or simultaneously of pitch.
MPE and aftertouch do not work as well for pitch, because it is difficult to slide your finger forward/backward to change pitch while playing, and pressure has to be designated pitch up OR pitch down. (This is a proof of concept/prototype. Ideally it would be made as part of the keyboard, with the arms protruding through slots on either side of the keys.)

The Thumb Bar Controller allows the performer to use the thumb of his playing hand to control both of these operations, leaving the other hand for playing another keyboard, visual expression, communication or direction, or other technical adjustments. It could be easily and inexpensively manufactured as part of the synthesizer, with openings on both sides of the keys for the vertical movement needed.
** It is up to players to request this from the manufacturers! **
More importantly, it allows a person with only one arm to be just as proficient as a person with two. Finally, a keyboard has been adapted for these people, instead of one more thing in life for which they have to adapt.