Toy Car Power Wheels Part 2

Toy Car Power Wheels Part 2

Jun 21, 2019

John Praleston

There have been many updates to the design of the manual throttle setup. I wanted to insure that the pedal would not get stuck leaving my son not in control of the car. I have finished the design for the throttle position potentiometer holster. I changed the fitment to come in from the bottom and be held in place by a nut coming from the top.

Very left – cap on holster design, Center – final concept design coming from bottom, right – first fitment check, way too wide for the application. The two gears below show the design change to ensure that the gear stays in position. I initially planned on holding it with two nuts but the potentiometer did not have enough thread length for that.


Here is a comparison from the initial concept design to the final version of the throttle arm. The threading is larger and guide rails have been added to keep the travel linear. The upper hole is for mounting to the pedal and lower hole is a stop pin to ensure consistent travel length.


The picture on the left is the concept of the guiderail. This will be bolted to the car to keep the gear and throttle arm in consistent contact.

 The next issue was the gear attached to the potentiometer was too far away from the pedal arm so I created a larger 19mm position gear.

I have tightened up all the steering linkage on the car but now am addressing the looseness of the steering gear assembly and steering arm. I printed a sleeve to take up the slack that was between the steering gear and arm. Each part that was loose would equate to an error in the steering calculations and output to the steering motor. I have two more components to design for this part. A potentiometer setup and gear to determine steering angle, and a bracket between the steering arm and steering linkage.

Above – here is a close up of the gap between the steering output shaft and the pin connected to the steering arm

Below – the steering sleeve, I added internal guides to keep aligned with output shaft of steering motor 

Here is the connection between the steering arm and linkage. I will be fabricating a bracket to mount between them with bearings to allow for motion

Lastly – the overall layout for the steering components. I will be designing the sensor mount to measure steering angle. The part in red is the base bracket that I will be mounting to (currently just to test fitment)