Sunday, February 20, 2022

The How


It took 6 months of building multiple prototypes, writing code and optimizing data, multiple failures, electrical calibration and re-routing of safety circuits, and finally in Feb 2022, a viable product was ready for it's first run.

But before we forget, let's look back at the journey how we got here

  • MobiMower 0.1 :- Didn't account for positioning and would continue to move the actuator back and forth with no dead zone in between.
  • MobiMower 0.2 :- Relied upon AI and visual feedback for the controlling arms. not deployment ready and discarded.
  • Mobimower 0.3 :- Worked with potentiometer feedback. clunky and prone to fatigue and failure. Eventually discarded
  • Mobimower 0.4 :- Didn't have RC sink circuit and froze the relay, paper capacitor replaced with an electrolytic capacitor
  • MobiMower 1.0 :- Worked on sensor feedback. Built with DC linear actuators. A closed loop system with ultrasonic sensors provides controls systems necessary feedback for accurate steering. Tripped safety switches and did not move the mower.
  • MobiMower 1.1 :- Added additional relays to turn safety switches on and off in sync to make the mower move. Success! Almost took down the garage (blooper video below).

Full test with emergency stop and description before it gets dismantled

  • MobiMower 2.0 :- Ready for install and test: built with stepper motors. An open loop system with fewer sensors required. an easy lock and go approach whenever it needs to switch from auto to manual mode.
  • MobiMower 3.0 :- In development: With GPS navigation, autonomous mowing and path planning.
  • Mobimower 3.a :- Potentially removing the actuators and directly hacking into the control module of the electric mower. specific to electric mowers with electronic control module
  • Mobimower 4.0 :- In future - potentially to work with traditional steering tractors/agricultural equipment

Next steps

  • Move from prototyping to production models
  • Migrate python code base to android and release app
  • Set up universal calibration steps.
  • integration with garage door
  • Add additional relays to operate other switches on the mower

The power surfing project

  01-Apr-2023: Sometime ago I had posted a video of a 400w trolling motor on my paddle board. It's a good option for a leisurely stroll ...