Help designing a voltage ramping circuit
This seems like a good application for direct digital synthesis (DDS) techniques.

Essentially this means writing a computer program (or a digital logic design) to generate digital values representing samples of the desired signal over time. Then use a digital-analog converter (DAC) to translate these to analog voltages. Possibly an analog filter may be used on the output signal to reduce digitization artifacts. And an analog amplifier might be used to increase the output power or voltage capability.

Obviously this is a very high level view. As you've heard from the comments on your question, the details of how this should be implemented (sample rate, sample resolution, filter details) will depend on the particular requirements of your application.