Introduction Of Haptic Feedback

What Devices Have The Best Haptic Feedback?

There is no doubt that it is Apple’s iPhone. Apple’s strategic investment in haptic feedback has started with the iPhone 6. Apple’s investment in haptic feedback motors is the largest in smartphone industry, and their products are also the most advanced, they’re leading haptic feedback technology. So iPhone users get the best haptic feedback experience.

According to the explanation of Wikipedia, haptics refer to any form interaction involving touch. Therefore it was always a tactile way to communicate through touch.

Since then scientists used vibration to present this tactile feedback method, and cleverly applied it to mobile devices such as replacing the physical keys of mobile phones. Unprecedented “haptic feedback” can be generated through novel vibration motors and Advanced Control Algorithms. The iPhone 7’s home button is an example of this, with a pressure sensor paired with “tactile feedback” instead of mechanical buttons.

Immersion is a company which has been working on haptic feedback algorithms since 1993. Over the past 20 years, more than 3 billion devices have adopted their haptic feedback technology, these include the controllers for Xbox and playstation games consoles, as well as many common mobile phone brands. Arguably, they are the most tactile company. In the eyes of their engineers, the biggest change to the iPhone 7 is actually “touch”.

Now you may wonder what kind of motor provides this kind of vibration feedback. At present, there are three kinds of small vibration motors.

– ERM – eccentric rotating mass
– Z – Quadrant LRA – linear resonant actuator
– X – Quadrant LVM – linear vibration motor

Different grades of motor in the shape (round shape, rectangle shape) , amplitude (up and down, left and right vibration) is very different. We can see that apple has invested a lot in the motor selection, which also helps it give a better tactile effect.

At present on the market many mainstream manufacturers’ flagship model all chose to use (LRA) linear vibration motor. Haptic technology has gradually become a chasing point for hardware equipment vendors. This is also a new technical concern and user side for hardware vendors to differentiate the user experience after digging to the extreme in the user experience of sound, vision, memory and other dimensions Innovation. Haptic technology has gradually become a chasing point for hardware equipment vendors. This is also a new technical concern and user side for hardware vendors to differentiate the user experience after digging to the extreme in the user experience of sound, vision, memory and other dimensions Innovation.

Here’s a brief overview of how different motors work on mobile phones, illustrated in graphic form:

The ERM has a lower price, less dynamic performance, and is now widely used in mid to low-end phones, pagers, and other wearable deivces that just need vibrating alert. Eccentric Rotating Mass motors, or ERMs, are typically DC-controlled motors of the bar or coin type. ERMs can be driven in the clockwise direction or counter-clockwise depending on the polarity of voltage across its two terminals.

Micro linear actuator will have strongest vibration force at their resonant frequency. This kind of small vibration motor need to be driven by IC, it is suggested to use TI’s DRV26XX series chips.

How To Choose The Right Haptic Feedback Vibration Motor?

The actuator decision is based on many factors including cost, form factor, vibration strength, power consumption requirements, haptic sharpness, reliability, and audible noise performance. The actuator selection is one of the most important design considerations of a haptic system and therefore the actuator should be the first component to consider when designing the system.
The following can be used to select the minimum required supply voltage.
1. Find the rated and/or maximum operating voltage in the actuator datasheet; some actuator datasheets may only have the rated voltage listed.
2. Using the larger of the rated and maximum operating voltage, add 250mV to get the minimum operating voltage. Adding 250mV provides operating headroom to account for internal driver losses.
3. Checkthesupplyvoltagetoensurethatthedesiredoutputisachieved.
A minimum supply current is also required based on the load. To ensure enough current can be sourced divide the supply voltage above by the load resistance in the actuator datasheet. Compare this number with the current capability of the battery or voltage supply.