After hinting in one of my other threads, I thought I should start a new thread for information, discussion and updates for a new project I'm working on
:
A replacement control system for those C5 without any or only part of the original electronic control systems, with the goal of provide a cheap replacement using off-the-shelf parts or reusing parts to hand, to provide optional basic pelalec law compliance and to provide "original C5 pod" LED like feedback.
First, Some background. My C5 was purchased from the previous owner who had removed the original control box and cut the wiring to the pod. Like some of the last C5 to leave the factory all that was left was a simple battery->switch->relay->motor configuration. While this works, it provides the rider with no feedback as to the state of the battery, motor temperature and current draw information or provide any way to "lock" the electrical systems of the C5. Due to my locale, the C5 in its current state class it as moped and this requires registration and testing, however at some point in the last 18 years or so this was not renewed and was driven illegally in a quiet mountain village. I am in the lengthy process of trying to track original documents etc to try and enable me be to legal on my C5 again, however I thought I would start work on a "Plan B" - to make my rudimentary C5 comply to the pedalec regulations enforced here in Switzerland and most of the EU with a fixed top speed of 25kph to re-class it as a E-Bike. To do this I need a new controller and having evaluated the ULA replacement option, I decided to make my own using a spare Arduino unit. The advantage of this is, that should I successful get the C5 registered as a moped, then I can still use the new Arduino pod controller for power/health/speed indicators etc and not use the pelalec part.
I envisage something along the lines of this (please excuse the crude overview at this stage, and sorry if you were expecting a completed circuit diagram and code already
):
I don't expect this be the final overview, and currently this matches the set-up I have planned for my C5 - ie my 24 volt motor doesn't uses any "kit" that converts existing cabling etc.
LED podThe pod unit is stripped of all but the original LEDs which are connected on a small board to some standard 74HC595 Shift registers. As well as freeing up outputs on the Arduino board, it allows the the main Arduino control board to be located away from the pod with only a few wires to connect them together.
A very basic test of the control of these LEDs from the Ardunio can been seen with
this video, please excuse the crude 80's link
Those without an original pod would simply be able to make a new LED array using what ever LEDs take your fancy
The main control board (the basic Arduino unit) with simply have a number of sensors and units connected to it.
SensorsFor the pelalec sensors, I have seen that this has been much covered on the forum, with the re-use of cycle compter switched or the install of new reed switched. At least 2 will be required, one for the pedal sensing and one for the speed sensing.
This thread shows the logic I have also planned.
For the current sensor I plan to reuse my existing Ampmeter shunt or
this Hall-Effect sensor . But I would plan to code to allow scaling to any shunt or monitor you have to hand.
2 Temperature sensor would be used to measure difference between air an motor temperature to allow better sensing of the motor.
Motor ControlThe main motor control will utilize one of the many Arduino relay Modules available. I plan to use
this one for example, which will sit in the same circuit as the handbar switch and motor relay. This means that what ever voltage is powering or system currently installed on the C5 (theoretically, even an original control system), it could be used to just use just the pedalec part of this project, if required
.
The code loop monitoring all these sensors would simply warn via LED, then switch off the motor control relay in cases of hot motor in conjunction say with repeated high Amp load or in pedalec mode high speed, lack of peddling etc
I hope that is clear (ish) and I realise that it is currently tailored to my current needs.
More to come soon, and I welcome any feedback or further ideas to be considered at this early stage.
Pat