Stopping in front of the dock was observed in the oldest Neato XV models (similar to VR100). The cause was traced to a defective diode on the system board involved in directing power between the battery, the charger, and the system. When defective battery voltage leaks back into the charging contacts in the rear. Voltage on these contacts is monitored by the software to determine whether the robot is connected to the charging dock. The robot stops because it thinks it has already docked. I do not know where this diode is on the VR200. Diodes and MOSFET switches redirect power according to whether the battery is charging etc.
Maybe focus adjustment should be done on a distant wall with room for beam to spread. The receiver lens is the important part. The lidar measures the parallax angle to the spot on the wall, as a range finder, using a camera sensor to measure position of focused spot on the sensor plate. So focus must be good on the sensor to measure accurately. Laser focus is needed to get a visible spot on a distant wall without excess beam spread. The maximum range is specified as 15ft, to keep power low for safety etc.
Sorry I do not have assembly details mentioned. There is a long two part demonstration video by an engineer refurbishing a Neato XV model which includes some work on the lidar, but the commentary is in English. He is actually not familiar with the Neato and just picked it up at a thrift store, but knows how to handle electronics
The motor speed appears to be only 1% off. I do not think the motor is the problem, but I have not repaired the lidars.
The slip ring in the VR100 may be a Vorwerk part with optical data coupling different from the Neato part, because when the Botvac was produced it used a Vorwerk improved slip ring. I do not know whether used on the VR100. The Neato part was discontinued but there are substitutes which can be adapted.
Below see all the links to Lidar information on English forum Robotreviews. I maintain a Wiki index thread there for Mods & Repairs.
Some people have adjusted the focus with the screw barrel, but it is a tedious procedure requiring repeated scans. It appears to be difficult to operate the laser apart from the spinning scan. The Lidar is a "smart" stand alone device with its own processor and a serial interface with text output and controls. The protocol was published so there are devices sold to operate the lidar outside the Neato.
Using a terminal emulator instead of Neato Control, you can see any error messages issued by the Lidar. Neato Control renders these as red colored areas in the graphics. The Neato text command manual is posted top of the Neato forum at Robotreviews.com. Neato echos characters back as typed to see immediately whether connected. Use Windows "devices and printers" or Device Manager to see the port number created by the Neato USB driver for Windows.
With a camera sensitive to IR you may be able to see the laser emission, especially on a paper closer to the robot with a couple feet for intensity. There have been photos made of the scan around walls with particular cameras especially sensitive to IR, in a dark room.
Lidar Motor Repair/Replacement
(and lidar mounting adjustment http://www.robotreviews.com/ch…opic.php?p=127197#p127197 from F_Robot)
Cheaper motor http://www.robotreviews.com/ch…opic.php?p=127592#p127592
"My Vision Was Blocked..." http://www.robotreviews.com/ch…opic.php?p=124047#p124047
"XV-11 Lidar Issues" http://www.robotreviews.com/ch….php?f=20&t=17893#p124922
Botvac Connected lidar motor http://www.robotreviews.com/ch….php?f=20&t=20364#p146974
Lidar drive belt -- O-ring 85x2mm nitrile NBR with 70 hardness. Ebay and Aliexpress.. Check details: http://www.robotreviews.com/chat/viewtopic.php?f=20&t=19453
--appears to be OD as standard DIN3771 for Vorwerk has 82 and 88 ID's, not 85. See post.
Lubricating Botvac lidar belt
Lidar Spin Bearing Replacement
A sealed bearing replacement is available at http://vic7767.com/neato-robot…rret-replacement-bearing/
Lidar Slip Ring (turret commutator) Replacement
Lidar Test Instrument "LIDAR RPM and PWM reports" http://www.robotreviews.com/chat/viewtopic.php?f=20&t=19060 (also has replacement lidars)
Also Arduino DIY lidar interface http://www.robotreviews.com/ch…&t=19881&p=143081#p143081
And Raspberry Pi interface https://hackaday.com/2016/01/2…ar-with-the-raspberry-pi/
Lidar Laser Diode Replacement
Lidar Internal Electronics
More Lidar repair, internals http://blog.avrnoob.com/2015/0…dar-repair-part-1-ir.html
Spin sensor alignment http://www.robotreviews.com/ch…opic.php?p=138197#p138197
Lidar lens focus adjustment, near-sighted http://www.robotreviews.com/ch…ilit=lidar+repair#p140958
Botvac Lidar Adjustment Screw
Neato Control or the USB text commands will show the rotation speed of lidar motor. The speed must be close to the specified 360RPM (I think), because it is used to time the rotation determining the direction of the laser. The most common repair is replacing this motor. The motor brushes wear out. There is an optical sensor for start of each rotation. Other failures can be the belt, the slip ring, the bearing. Sometimes the laser diode is replaced.
When replacing the motor, sometimes the wires must be reversed from the original for correct spin direction counter clockwise.
Sorry I forgot that the SetConfig system was abandoned in the Botvac series while used in the XV models. Botvac had entirely new firmware and OS. So this option would not be available for the side brush. There might be a separate side brush enable command. The HELP command lists all commands available.
If the D3 has a USB port, there is a remote possibility it would respond to the unpublished text command SetConfig for the side brush, I would have to research. The difference between the D3 and D5 might be configuration settings instead of purely firmware code differences. SetConfig BatteryType was used to distinguish NiMh and Lithium battery charging between Neato and Vorwerk sharing the same system board and firmware. I think there is a command Brush Enable/Disable, but haven't used myself. Of course, the hardware components for it might not be on the D3 system board, in which case the connector pins for the motor cable should also be absent, unpopulated board traces.
If there is a USB port on the D5, the Neato Control Program. Otherwise, voltmeter measurements would be needed. The sensors measure the distance to the floor with a varied voltage output. Software then interprets this input. It is possible that the sensors would be detected as a sensor defect. This depends on the software. There are USB commands which calibrate some of the sensor readings.
Many of these black floor situations have been fixed by covering the sensors, but every model is different.
All brands of vacuum robots can fail to travel over certain black floor material. Only certain materials cause the problem. The robot avoids the black surface because of a false indication by the cliff or drop sensors on the bottom of the vacuum. These sensors detect drops such as stairs. They prevent the robot from falling. The sensors operate by detecting infrared light reflected from the floor. The black materials absorb the infrared light and prevent reflection to the sensor. The technical term is IR Proximity Sensor. The same type of sensor is used for the Neato Wall Sensor. There are superior optical methods available but they are not common or too expensive so not yet used in the vacuum robots.
The problem can be corrected by placing light colored tape such as masking tape over the sensor on the bottom of the robot. The tape will create a false floor which substitutes for the black material. When the sensor is disabled in this way, it will no longer detect actual cliffs. Other barriers such as magnetic tape can then be used at stairways etc.
For more technical information see English forum post http://www.robotreviews.com/chat/viewtopic.php?f=4&t=19897
A common fault in the Neato robots is the optical Wall and Cliff sensors, detecting reflected infrared light. False indications from defective sensors can cause an apparent trapped condition. The Wall sensor could indicate walls in every direction, trapping the robot. These sensors are inexpensive and sometimes replaced by users. However, this was true on the older non-wifi models D85 etc., not the newer D5,7 etc. I do not know what parts are in those new models.
In the older models, a USB port exists which can be used with Neato Control Program showing status of the sensors allowing identification of defective sensors, including perfromance of the lidar scanner.
There are several different causes of the robot shutting off. Special tests are needed to identify the cause in a particular case. A commercial repair service would replace parts until it works.
To analyze the battery, a volt meter should be applied to the battery removed from the robot. The specifications of the battery, voltage etc., must be noted.
I do not have the specifications for this robot. I use a Samsung Powerbot.
When the robot shuts off, does it show any error message on the screen?
One reason Samsung robots will stop is because a switch in the drive wheels indicates the robot is lifted off the floor. I had to disable this switch in the Powerbot. This depends on the particular model and driving characteristics, weight distribution etc. It depends on the software, how it handles this signal. Other brands can perform differently.
When the robot stops, is the battery voltage different when first measured?
The robot circuits contain electronic switch components, Mosfets and diodes, which direct power between the charger, the battery, and the circuits, according to whether the battery is charging or the robot is cleaning. A fault in these components could prevent battery power from operating the robot, even though it works when powered by the charger.
When analyzing the powerbot, I can operate it on a table by supporting it on blocks under wheels, and use the manual control in the remote control. I do not know what can be done with Navibot, a much older product.
It is possible the charger is not working. There are many different faults possible in the electronics. Analysis with instruments is needed.
There could be errors in the product description because it is not very precise. It is not clear how a battery can detect whether the robot is programmed for lithium charging procedure -- The VR100 -- or is programmed for NiMh charging, Neato. The procedure in the XV models is configured by a USB command SetConfig BatteryType, applied in software updates. The Neato models can be switched to lithium batteries with this command. Lithium replacements for the NiMh batteries in the past include an adapter which simulates the NIMh behavior for the charger. That would not work in a Vorwerk expecting normal lithium batteries. I am not sure this seller understands what they are selling, however good it may be. Dealers do not always understand products which they obtain from engineering companies.
In some cases the MAXIM fuel gauge IC has needed replacement for defects. Operation can be observed over USB with the Neato Control program or terminal emulator, examining the Fuel Gauge per cent and battery temperature. The NIMh battery charging terminates when temperature rises faster than 1C per minute. The NIMh chemistry dissipates charging current as heat when the battery is full. Lithium chemistry requires termination of charging when the maximum voltage is reached, without heating.
Neato Control shows the dock voltage zero, "external voltage". The dock is defective, or not plugged in, or the robot is not docked on the charger.
I received an email of the above post and sent a reply, but perhaps it does not go through this system.
The multimeter must be set to DC voltage. AC mode will read zero on AC. "mv" is millivolt, 1/1000 volt.
There have been defective docks which need replacement. Tests are needed to identify which part is broken. Use the Neato Control program in other threads here with the USB connection to PC.
The contacts on the dock should show near 18v. Your measurements show effectively zero. The dock is not operating.
Beveled wood moldings are in building supply for window framing.
Rubber ramps are made in a wide variety of sizes for wheel chair access through doors. Some only 2.5cm high.
Another material is electrical cord covers for floors, which might be cut into two pieces and taped across thresholds.
I think to see the Wall Sensor and Mag Strip Sensor data correctly in Neato Control, Test Mode must be engaged by a command or button if shown. There is an option to issue text commands. "TestMode ON". The program uses a text command language built into the Neato firmware.
The cliff or drop sensors use the same component as the Wall Sensor but may have a different display in the program. Test moving a hand close and away from these optical sensors. The negative numbers shown in the picture posted above are not correct readings.