While posting here on SlotForum about some car builds in Scratch Building I thought I may as well share with you my scratch built hand controller. I hope this is the most appropriate forum... Im sure Ill receive a post or two if it isnt.
Im not much of an analog electronics person but can hold my own with digital, programming, repurposing stuff and working things out for myself... just the right skills (I hoped).
The basis of this controller is:-
A microprocessor to receive signals from a hand controller and adjust he output of a dual MOSFET speed controller. The microprocessor has access to car/track voltage and current if I write the code to use this additional information.
A wireless connection between the hand controller and the magic box.
Control via switches and potentiometers on the box to adjust any of the settings in the algorithm that controls track power and braking.
LEDs on the box that lets me debug the code and see what is going on when in use. You cant watch the lights while racing but I can watch what other (much better racers than me) people are doing when they use it.
My algorithms allows:-
Speed and braking to be controlled
Mapping to allow the relationship of the trigger position and track power to be adjusted. Two map shapes are possible and may be adjusted through 256 steps from one extreme to the other of each.
Snatch control adjustment to soften the power delivery when the trigger is snatched on.
Start/minimum power as a percentage of full power. That is the voltage delivered once the trigger is moved.
Full power adjustment as a percentage of that available from the track power source. It happens at full trigger pull position.
Coasting power. This is a percentage of the full power and comes into play when one of the buttons on the hand controller is pressed. Coasting can be either set to be controlled from minimum to coast power or coast power to full power.
No power braking can be adjusted from 0% to 100% that the back EMF from the motor is capable of giving.
Roll braking is adjustable from 0% to 100% but comes into operation whenever the trigger is released even if it isnt fully released. This means you can get some braking force without having to come off the trigger completely.
The hand controller is powered by a battery inside the handle and the box by a battery on the top or from the PC is connected for development purposes.
The hand controller is typically me and is a reworked Scalextric (with a useful little hand extension made from a Hermasetas container! All the electronics inside is replaced and built onto a new platform. Trigger feel is exceptionally smooth and can be very light but has had an additional spring fitted to the trigger. The trigger is on its fourth shape and now feels about right.
For the time being the insides of the box are partly built on a breadboard so I can change things around easily. Consequently it looks a bit of a rats nest inside.
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Im not much of an analog electronics person but can hold my own with digital, programming, repurposing stuff and working things out for myself... just the right skills (I hoped).
The basis of this controller is:-
A microprocessor to receive signals from a hand controller and adjust he output of a dual MOSFET speed controller. The microprocessor has access to car/track voltage and current if I write the code to use this additional information.
A wireless connection between the hand controller and the magic box.
Control via switches and potentiometers on the box to adjust any of the settings in the algorithm that controls track power and braking.
LEDs on the box that lets me debug the code and see what is going on when in use. You cant watch the lights while racing but I can watch what other (much better racers than me) people are doing when they use it.
My algorithms allows:-
Speed and braking to be controlled
Mapping to allow the relationship of the trigger position and track power to be adjusted. Two map shapes are possible and may be adjusted through 256 steps from one extreme to the other of each.
Snatch control adjustment to soften the power delivery when the trigger is snatched on.
Start/minimum power as a percentage of full power. That is the voltage delivered once the trigger is moved.
Full power adjustment as a percentage of that available from the track power source. It happens at full trigger pull position.
Coasting power. This is a percentage of the full power and comes into play when one of the buttons on the hand controller is pressed. Coasting can be either set to be controlled from minimum to coast power or coast power to full power.
No power braking can be adjusted from 0% to 100% that the back EMF from the motor is capable of giving.
Roll braking is adjustable from 0% to 100% but comes into operation whenever the trigger is released even if it isnt fully released. This means you can get some braking force without having to come off the trigger completely.
The hand controller is powered by a battery inside the handle and the box by a battery on the top or from the PC is connected for development purposes.
The hand controller is typically me and is a reworked Scalextric (with a useful little hand extension made from a Hermasetas container! All the electronics inside is replaced and built onto a new platform. Trigger feel is exceptionally smooth and can be very light but has had an additional spring fitted to the trigger. The trigger is on its fourth shape and now feels about right.
For the time being the insides of the box are partly built on a breadboard so I can change things around easily. Consequently it looks a bit of a rats nest inside.
