Significant risks and risk management:
Risk: The analog circuit as described by Sergey’s Thesis cannot be realized.
Definition: Through some more research and implementing his circuits through simulation, we were able to determine that the constraint primitives are not able to be realized for our optimization problem. Specifically, for the equality constraint, the theoretical formulation assumed infinite op amp rail voltages and the quadratic costs could not properly be realized without first solving a linear programming problem.
Severity: The severity is very high. If this is not able to be resolved, our circuit will fail to converge.
Resolution: We were able to resolve both of these issues. For the inequality, we reduced the operating voltage by 10x, so that the maximum voltage that we expect is within the rails of the op amp. As for the costs, we realized that we could not implement these quadratic costs for SQP without first solving a SLP (sequential linear programming), so we decided to compromise and solve our optimization problems using an SLP, using linear costs.
Current progress:
Apart from the risk identified from last week, the current big risk in our project is the uncertainty of whether or not we can create a working solution. We are putting in a lot of work to modify the circuit design so that the circuit is able to perform our needed calculations while remaining within the physical limits of the components, which is something that Sergey did not consider with his design. At the same time, switching from SQP to SLP means that the problem formulations need to be rederived, which will inevitably put us behind schedule. However, we are currently making good progress to both having a workable circuit simulation and a correct SLP formulation.
Changes to the existing design:
Apart from the changes described last week, we have successfully simplified the analog circuit to include less components by exploiting some of the structure within the problem. We also changed the problem we are trying to solve from a double pendulum to a single dampened pendulum to make it less non linear while making it still interesting.
Changes to the project schedule:
There are no significant changes to the project schedule, we are trying to complete the circuit simulation as soon as possible so that we can start to order pcbs.