Punch in Air #2 Experiments on Function and Performance of MAX25405 IR Sensor Evaluation Kit

Punch in Air #2 Experiments on Function and Performance of MAX25405 IR Sensor Evaluation Kit

1 Brief Summary on Functions and Performance Experiment

As mentioned in Punch in Air #1 About Punch in Air Experiments on MAX25405 Optical IR Sensor Evaluation Kit - Challenge Blog - Experimenting with Gesture Sensors - element14 Community. Unboxing the MAX25405 IR Sensor Evaluation Kit, run the demo desktop application to validate the function. In this Punch in Air #2 Experiments, try to answer two questions about MAX25405 IR sensor, what it 'sees' and what range it can 'see', to find out the detection range and abilities.  Brief result is,

The Function,

The MAX25405 IR sensor can detect short range objects, different reflection characteristic such as color or material matters, the irradiation temperature matters.

The Performance,

The detection range is in size of radial cone, only gesture within this range works out.

2 Preparation 

Prepare one desktop computer with MAX Sensor GUI installed. In this case, one portable Microsoft Surface is good for this purpose

Prepare one rotary support frame, holding the  MAX25405 IR Sensor Evaluation Kit in position and One Tripod Supporting the moving objects.

Prepare one large size white board as clear background,

Prepare 0~40m Laser Distance Meter, one 5m long roll meter, one infra temperature Meter 

Arrange all above in one Room with Heavy curtain and adjustable Lights.

3 Various Material and Size of Object

3.1 Arrange the experiment scene

Put the surface on desk, connecting the MAX25405 IR Sensor Evaluation Kit with Micro-USB wire and plug the 3.3V power supply as well.

The MAX25405 IR Sensor is held on adjustable supporting frame, facing direct to longest side of room with Large white board as movable background. One tripod is placed just opposite the MAX25405 IR Sensor Evaluation board, holding various type of objects.

{gallery}My Gallery Title
Large size cotton
Large size cotton in MAX GUI heat map

3.2 About the ambient light 

According to the Reference manual of MAX25405 IR Sensor, the 6x10 sensor array take picture in two steps. First, catch the sensor value with normal ambient light without the IR LED flashed. Second, take the senor value with IR LED flashed in normal ambient light.  This effort eliminates the impact of ambient light. This algorithm is impressive. From fully illumination with light or sunshine to poorly illumination with heavy curtain covered. The Heatmap in the MAX GUI shows no difference. As dark as picture below,

3.3 About material and color

Change the detect object with hand, human body, green cotton, black hat, pink hat, white hat, yellow cotton, white cup with cold water, white cup with hot water. Here is some interesting results,

- Unlike the requirement in Reference Manual, the body behind the hand shows little impact on Gesture Detection result, since the hand is closer to the MAX25405 IR Sensor. In this case, body is just kind of noise factor blending with background.

- The Material and color are factors not to be neglected. Further reasons are not clear for now. It can be figured that reflective factor is important. Larger size object shows large value and darker color in Heat Map on MAX GUI application. Hands can be regarded as portable object, if wearing gloves, there is little difference.

- The Temperature of object is important factor in MAX25405 IR Sensor detection.  

For size and color of pictures, refer to pictures in the other part of this blogs.

4 Range of Detection

4.1 Background and Distance

According to this experiment, objectives 1 meter away can be part of background and show little impact on MAX25405 IR Sensor.

Here are some screenshots on Heat Map on MAX GUI applications.

Body as Background in 0.5 meter or 1.5 meter shows little difference.

White board as Background in 0.5 meters, 1.0 meters, 1.5 meter, 2 meters, and 6 meters shows little difference.

Dark/Light White board as Background in 6 meters shows little difference.

4.2 Temperature and Distance

Cold/Hot water in cup in 0.2 meters, 0.3 meters, 0.4 meter 

4.3 Detection range in cone size

Moving hand in front of The MAX25405 IR sensor until out of the brim of Heat Map in MAX GUI application, trace the moving heat dot in the view as below

With the help of toothpick and cotton wire, in the end, outline the detective range of MAX25405 IR sensor, the rolling ruler below show the distance and size 

This can be of useful in functional design of projects.

5 Gesture Sensitive

Repeat the experiment in previous blog, test the sensitive of all the gesture actions. The results turn to be very successful. Within 0.5 meters, arrow gesture like up-down-left-right-rotary can be clearly detected. Out of 0.6 meter, the gesture is hard to detect. It shall be remarked that in Heat map, the detective range is about 0.3 meter, just as in previous cone in experiment  4.3. In fact ,the gesture sensing range is double, up to 0.6 meters.

Exclude that Press Gesture with Large Dot sign, which detect proximate distance of object as Proximate Tab shows below.

6 Conclusion

In general, from this experiment on function and performance, it can be learned that,

- MAX25405 IR Sensor can detect gesture within 0.6 meters range and valid open range over 120 degree. 

- There is barely background influence beyond the distance of 0.6 meters.

- Any object can reflect IR can be used, besides hands

- Higher temperature can argument the detective range and sensitive, but normal ambient environment is enough for most cases.

Based on this conclusion, further interesting projects can be designed with MAX25405 IR Sensor .