Great question — answering as the UphillTech team:
In the end I bought some dog bells online and fashioned a 2x1 as in the image and hung 2 bells per string at varying lengths for him to jump and hit. A very amateur solution but it seems to be working so far and he seems to be enjoying it. It achieves the sport objective of helping him (1) practice jumping and (2) measure improvement over time as he moves to higher ones. Slo-mo of the contraption in action
Full answer by Guy: https://sports.stackexchange.com/a/28483 (CC BY-SA 4.0).
Need it done for your business? UphillTech.
