Potentiometers are three-terminal resistors that are typically used to control electrical devices as position transducers, for example, in an industrial joystick.

There are two types of potentiometers – traditional analog potentiometer and programmable digital potentiometers. Each can be customized to include added features. By adding mechanical detents, you can help ensure that an operator adjusts a knob or joystick switch to the correct position. For example, joysticks with center detent potentiometers are easy to return to the exact center. This is particularly useful in industrial environments where vibration may inadvertently reposition the knob or joystick switch.

Mining Vehicles Requiring Joysticks

Mechanical detents can be customized to deliver sensory inputs to the operator in the form of clicks or force and friction. In this case, the potentiometers are manufactured with dimples that cause them to click into place at certain positions.

All of these custom features are designed with the operator in mind. Small customizations can increase productivity and safety.

A Primer on Mechanical Detents

Detents provide a means to resist or arrest the rotation of a wheel, axle, or spindle. This may include a number of devices, ranging from a simple metal pin to a joystick handle. In the case of a joystick, an operator may feel a distinctive click when the joystick switch has engaged the detent, holding it in a certain position.

While detents can be useful in a number of scenarios, they are particularly valuable for machinery in industrial environments. Mechanical detents can prevent accidental repositioning of a joystick, which would otherwise lead to unwanted movement of the machinery. That could be dangerous for nearby workers or cause unintended damage.

Mechanical Detent Machinery Examples

  • Material Handling in discrete manufacturing
  • Off-road vehicles for construction
  • Mining and excavating equipment
  • Forestry and agriculture equipment

Joysticks made using potentiometers with center detents, are easier to return to the exact center of their range and stay there. With additional customizations, potentiometers can be engineered to deliver certain controls to equipment that match with the detent’s location. 

Engineering Potentiometers with Detents

When it comes to creating these potentiometers, their detents will resemble little dimples that stick out. When the potentiometer is in the center, the point sticks into the dimple and clicks into place. Center detent potentiometers allow joystick operators to feel the true center.

It is also possible to add different levels of torque to detents. The majority of detents used for potentiometers will vary from 1.2 to 2.5 times the standard potentiometer torque. One example of using the different levels of torque is to assign a higher torque position for the center. In industrial environments with high vibration, it could be crucial that the joystick stays in the center position unless moved by the operator. Increasing the torque level for the center detent is a great way to do this.

Detents Used to Improve Joystick Control

When using a center detent, the joystick operator moves the handle across either one or two axes and can tell when the joystick crosses over the absolute center. The operator will receive tactile feedback requiring additional force to remove the joystick from its center detent position. Increasing the torque of the central detent potentiometer can increase the feedback or require the controller to add more force to move the joystick handle outside of the center.

In cases where an operator is at the helm of multifunction controls, having this extra layer of feedback can go a long way. Mechanical detents provide more input to the operator in the form of clicks, friction and force, and automatic re-centering so that it is easier to memorize movements internally. All of these functional elements help increase the precision of the machine in use.

Custom Potentiometers

Customizing potentiometers with detents goes a long way to improving the functionality of joysticks and other controls. Strong and weak detents (stop positions) can be mixed to meet project specifications. Constant voltage zones can be combined with mechanical detents to provide exact alignment between the electrical output (flat areas) and the mechanical detent’s positions. The result is a higher level of precision in controlling machines, equipment, and industrial systems.

Custom engineering potentiometer

This provides clear mechanical positions that are not only repeatable but perfectly aligned electrical outputs at each of the (detent) angles. Detents also prevent output values from changing due to vibration or accidental rotor movements, furthering reliable control consistency.