Adding Rudder Control to a Putt Putt or Pop Pop Boat
- Putt putt boats or pop pot boats are inexpensive toy boats that are fun to use. They basically use a simple steam engine, a boiler that is mounted in the centre of a boat frame and when water is filled into the boat heater pipes and heated at the boiler, it causes steam to be expelled from one of the pipes which causes more cold water to be sucked in. The expulsion of the steam causes the boat to move forward and creates a suction/expulsion cycle.
- As the only motion that is provided is forward motion, it would be very desirable to have turn control. This is done by using a rudder.
Implementing the Rudder Control on the Putt Putt boat
- This mechanism needs a rudder a piece of metal/wood/plastic and turns left or right depending on the control from the user.
- To achieve this mechanism, simple off-the-shelf parts or parts available from the numerous online electronics hobby stores were chosen.
- A simple SG90 servo can provide the left, center and right turn capability.
- As this needed to be wireless a wireless controller with either WIFI or Bluetooth would be necessary. As WIFI is easier to implement and the UI can be provided via a web browser a WIFI chip was chosen. As it had to be small in size an ESP-01 was used. ESP-01 has some 4 usable pins.
- A small web server and servo control were implemented and using chrome web browser one could send relevant turn instructions wirelessly as clickable text links.
- To power this tiny circuitry a tiny 200mA Lithium-ion battery was used. But the ESP-01 only works at 3.3V and this regulated voltage needs to be fed to its Vcc/Input Voltage pin.
- There is buck-boost voltage converter available on the electronics hobby stores that uses a Li-ion battery voltage from 1.8V to 5.5 V(even down to 2V) and either boosts it or reduces to 3.3 regulated voltage. The product is linked here 1.8V to 5.5V to 3.3 V buck/boost converter.
Rudder control
- Above is the picture of the implemented rudder control and the mounting.
- The above video shows the rudder servo operation.
Implementation outcome
- The rudder side servo turned out to be too heavy for this light boat and it would tend to drown the boat.
- So this attempt has to be discontinued and a new stronger frame has to be used or built.
- Updates on the next frame in a later post.
- Below is a video of a free running putt putt boat.
