VL6180 Optimal Settings for Acuracy

[gerbers]

I am using the VL6180 (not the X version).  This is TOF only.  When reading in continuous mode, I'm getting a tolerance of +/- 1mm and sometimes more.  I'll list my settings below.    My application will measure distances from 10mm to 100mm.  Right now I have the inter-measurement period set to 500ms and this is flexible.  How can I optimize my settings further for accuracy? thanks

VL6180_WriteByte(0x0207, 0x01);  
VL6180_WriteByte(0x0208, 0x01);  
VL6180_WriteByte(0x0096, 0x00); 
VL6180_WriteByte(0x0097, 0xfd);  
VL6180_WriteByte(0x00e3, 0x00);  
VL6180_WriteByte(0x00e4, 0x04);  
VL6180_WriteByte(0x00e5, 0x02);  
VL6180_WriteByte(0x00e6, 0x01);  
VL6180_WriteByte(0x00e7, 0x03); 
VL6180_WriteByte(0x00f5, 0x02);  
VL6180_WriteByte(0x00d9, 0x05); 
VL6180_WriteByte(0x00db, 0xce);  
VL6180_WriteByte(0x00dc, 0x03);
VL6180_WriteByte(0x00dd, 0xf8);
VL6180_WriteByte(0x009f, 0x00);
VL6180_WriteByte(0x00a3, 0x3c);
VL6180_WriteByte(0x00b7, 0x00);
VL6180_WriteByte(0x00bb, 0x3c);
VL6180_WriteByte(0x00b2, 0x09);
VL6180_WriteByte(0x00ca, 0x09);
VL6180_WriteByte(0x0198, 0x01);
VL6180_WriteByte(0x01b0, 0x17);
VL6180_WriteByte(0x01ad, 0x00);
VL6180_WriteByte(0x00ff, 0x05);
VL6180_WriteByte(0x0100, 0x05);
VL6180_WriteByte(0x0199, 0x05);
VL6180_WriteByte(0x01a6, 0x1b);
VL6180_WriteByte(0x01ac, 0x3e);
VL6180_WriteByte(0x01a7, 0x1f);
VL6180_WriteByte(0x0030, 0x00);

 // Recommended : Public registers - See data sheet for more detail 
VL6180_WriteByte( 0x0011, 0x30); // Active high. Interrupt enabled
VL6180_WriteByte( 0x010a, 0x30); // Set the averaging sample period (compromise between lower noise and increased execution time)
VL6180_WriteByte( 0x003f, 0x46); // Sets the light and dark gain (upper nibble). Dark gain should not be changed.
VL6180_WriteByte( 0x0031, 0xFF); // sets the # of range measurements after which auto calibration of system is performed 
VL6180_WriteByte( 0x002e, 0x01); // perform a single temperature calibration of the ranging sensor 

// Optional: Public registers - See data sheet for more detail 
VL6180_WriteByte( 0x001b, 0x31); // Set default ranging inter-measurement period to 500ms (changing from 100ms or 0x09 to 500ms 0x31)
VL6180_WriteByte( 0x0014, 0x04); // Configures interrupt on New sample ready 

VL6180_WriteByte(SYSRANGE_MAX_CONVERGENCE_TIME, 0x3F);  // 0x14 = 20ms
VL6180_WriteByte(SYSRANGE__START, 0x03);  // Bit 1 = 0 (single shot).  Bit 1 = 1 (continuous mode).

[Zhiyuan.Han · Accepted solution]

Hi 

From your shred range result performance, I think +/-1mm is already the best case with 6180 sensor, if you want more accuracy, what I can suggest is applying a post-process rolling average if possible.  rolling average will give you a better accuracy but will lead time legacy, you can try with still or low speed target, not suggested for fast moving target.

Br

Zhiyuan.Han