Microchip AVR DA MCU-based multi-function steering wheel solution with heated HoD, hand-off detection and touch

Currently, more and more cars are equipped with advanced driver assistance systems (ADAS). According to regulations, drivers should keep their hands on the steering wheel so that they can quickly take over the vehicle in an emergency. Therefore, HoD (Hands-off Detection) technology is very necessary.

There are currently two mainstream HoD detection solutions on the market:

Steering torque detection solution:

It detects the torque applied to the steering wheel to determine whether there are hands on the steering wheel.

The advantages are simple principle and low cost.

The disadvantage is that it is easy to be deceived. For example, by hanging an object of appropriate weight on one side of the steering wheel, the detection can be deceived.

Capacitive touch detection solution:

It detects whether there is a hand controlling the steering wheel by detecting the impact of the human hand on the capacitance of the steering wheel to the ground.

The advantage is that it is not easily deceived and can detect in different areas to determine the grasping gesture and position.

The disadvantages are that the technology is relatively difficult, the impact of heating on capacitance detection, the impact of gloves on the signal, and the consistency of the sensor put higher requirements on the software processing algorithm.

Microchip's solution not only realizes the HoD function, but also integrates touchpad, buttons, sliders, rollers and other functions to realize a touch multi-function steering wheel, which reduces system costs and improves the human-computer interaction experience.

Microchip AVR DA MCU-based multi-function steering wheel solution with heated HoD, hand-off detection and touch

► Display board photos

►Solution Block Diagram

Microchip AVR DA MCU-based multi-function steering wheel solution with heated HoD, hand-off detection and touch

►Core technology advantages

Microchip's HoD hand-off detection + touch multi-function steering wheel has the following technical advantages:

1. AVR DA MCU single chip realizes HoD hand-off detection + touchpad, button, slider, and scroll wheel functions, reducing the overall system cost.

2. Support three-layer, double-layer, and single-layer sensor structures, support steering wheel heating, and have a wide range of applications.

3. Support HoD partition detection, which can determine the position and gesture of human hand grasping.

4. Touchpad gesture recognition: sliding direction, rotation direction, single click/double click. Rich human-computer interaction experience.

5. Drive shielding technology can improve capacitance detection performance and support touch with gloves.

6. Expandable tactile feedback (vibration/sound/flash), ISELED driver.

7. Low-cost, high-performance automotive-grade MCU that meets ISO26262 functional safety requirements.

8. External LIN SBC can realize LIN communication, and external MCP25625 or MCP251863 can be used to expand CAN/CAN-FD communication through SPI.

9. Convenient development environment, visual parameter debugging, complete reference design materials, strong technical support team, and rapid market launch.

►Solution Specifications

Advanced Driver Assistance Systems (ADAS)

HoD Hands-off Detection

Touch multi-function steering wheel (touch panel, buttons, sliders, scroll wheels, gesture recognition)