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The majority of this day was spent on a Skype call with Andy, addressing the conceptual issues with the ergometer. 
The main problem we were facing was how to match the gear ratios to what they were with the floating pulley. While Andy had been suggesting that we put the wheel chain in the center of the differential instead of the handle chain, we were nervous about this because of what a major change it would be.
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However, Andy additionally pointed out that axel #5 was still unnecessary. We could eliminate the extra axel by putting that new soft bungee right underneath the hard bungee that was already there. After this discussion with Andy, we were left with this design:
Figure 1: Rowgometer Setup
Shortly after calling Andy, we put together a schedule for the week:
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After we ordered the sprockets, we started to figure out how to actually assemble the system labeled B2 on figure 1. We took the stiff bungees that we coiled over themselves several times (figure 2,) and took one more bungee off, taking it down to three total. We did this because with the four bungees it had before, it barely stretched no matter how much you pulled on it. We removed the bungee so it could actually stretch a little bit, allowing it to act more like a bungee and less like a chain.
Figure 2: The Stiff Bungees
We then went hunting for a soft bungee to put in parallel with the spring on the top. The only purpose of this bungee is to collect the chain, to it doesn't need to have a high force. In fact, it's best to keep the force small because the higher the force this bungee exerts, the more resistance the rower will feel. It needs to be stiff enough to collect the chain slack, but nothing more.
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For the loose bungee on top, while it would be easy to attach the one end to the stern, how to attach it to the chain half way across the erg was a challenge. The only solution we could think of would be to wrap something really tightly around the bungee and the chain, and hope there is enough friction to hold the two together. We took a twist tie and wrapped it around the two, and hoped for the best. (Figure 3)
Figure 3: Twist tie around the bungee and chain
To hold the loose end of the bungee, we looped it around itself a few times and taped it beneath the footrests so it's out of the way. The system, as a whole, looked like figure 4.
Figure 4: The completed Setup
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