Following on from adding support to wiringPi for the MCP4725 DAC, I wanted to add driver blocks to Simulink such that one could use them to create graphical models for the Raspberry Pi that could interface with the real-world – a workable alternative to expensive real-time targets.
Simulink Embedded Coder offers an ARM Cortex-M support toolbox, which includes code optimisation for the MCU and QEMU emulation but lacks any S-Block drivers for the device. The lack of drivers limits the Simulink development to merely number crunching. You can create
cevel blocks that execute external C functions but this requires separate source files with a shared header and pre-defined initialisation, leaving the model without full control of the hardware. In this post, I go over the process of creating hardware driver S-Blocks.
One module I took during the final year of my degree was ‘System Modelling and Simulation’. A well taught and great module, one of the tasks was to model a double pendulum.
The approach involved deriving the equations of from the highest order of motion for each mass then working backwards through Simulink blocks to generate each term, which could then be to solve the equation – a bit of a chicken and egg problem! It was a an excellent task as the idea seems a little backwards at first and gave me a fresh approach to problem solving a model.
Below is the method extract from my report as the YouTube demo has generated some interest in the solution.