Required parts and tools<\/h3>\n\n- An Arduino Uno or compatible board.<\/li>\n
- Two<\/strong> geared motor and wheel sets. This is Siratek product 7406; one set is one wheel.<\/li>\n
- An L298N driver module, Siratek 2533.<\/li>\n
- A separate motor supply, four to six AA cells or a 6 V pack.<\/li>\n
- A chassis, or something to screw the motors to, and a castor or ball wheel at one end.<\/li>\n
- A soldering iron, because the motor terminals arrive bare.<\/li>\n<\/ul>\n
What you are getting<\/h3>\n
The Siratek photographs show the common yellow TT gear motor<\/strong>: a small brushed motor in a metal can, a yellow plastic gearbox, a shaft projecting from each side, and a black rubber tyre on a yellow plastic hub.<\/p>\nTypical figures for this type:<\/p>\n
\n\n\n<\/th>\n <\/th>\n<\/tr>\n<\/thead>\n \n\nSupply<\/td>\n 3 to 6 V<\/td>\n<\/tr>\n \nGear ratio<\/td>\n about 1:48<\/td>\n<\/tr>\n \nFree-running current<\/td>\n roughly 150 to 200 mA each<\/td>\n<\/tr>\n \nStall current<\/strong><\/td>\nclose to 1 A each<\/strong><\/td>\n<\/tr>\n\nOutput speed at 6 V<\/td>\n very roughly 200 revolutions per minute<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nThe stall current is the number that matters.<\/strong> Two motors stalled is about 2 A, which is far beyond a USB supply and more than a weak battery pack will hold up under. A robot that resets when it hits a wall is this, not a software fault.<\/p>\nThe shaft goes through<\/h3>\n
The motor has a shaft on both sides. One takes the wheel; the other is spare, and is there so you can fit an encoder disc if you later want to know how far you have travelled.<\/p>\n
Push the wheel on firmly. The hub is a tight fit on a D-shaped shaft and it only goes on one way round.<\/p>\n
Solder the leads before mounting anything<\/h3>\n
The terminals are two small metal tabs with no wires attached. Solder leads on before<\/strong> you screw the motor to a chassis, because afterwards the tabs are awkward to reach and the heat is harder to manage.<\/p>\nKeep them short, use stranded wire so they flex, and add a dab of hot glue over the joint: those tabs break off easily if the wire is tugged.<\/p>\n
Two motors will not run at the same speed<\/h3>\n
This is the thing that surprises people, so it comes before the wiring.<\/p>\n
Give two identical motors the same voltage and the robot curves. Always. The gearboxes differ a little, the brushes differ, the friction differs, and the difference is often ten percent or more.<\/p>\n
There are three honest responses:<\/p>\n
Trim it in software.<\/strong> Measure how much each motor needs to go straight and apply a correction factor. Simple, free, and only right at one speed and on one surface.<\/p>\nFit encoders.<\/strong> The spare shaft takes a slotted disc, and an optical sensor counts the slots. Then the sketch knows the actual speed of each wheel and can correct continuously. This is the proper answer and it is a project of its own.<\/p>\nDo not need it to go straight.<\/strong> A line-following robot corrects its heading constantly from the line itself, so the motors never need to match. That is why line following is the natural first robot: the mismatch stops mattering.<\/p>\nThe sketch below includes the trim, because it is the first thing anyone needs.<\/p>\n
Which way is forward<\/h3>\n
Swapping a motor\u2019s two leads reverses it. Because the two motors face opposite ways on a chassis, one of them will almost certainly need its leads swapped<\/strong> for both wheels to drive the robot in the same direction.<\/p>\nExpect this rather than being puzzled by it: the first time you run both motors forward, one wheel will turn backwards. Swap that motor\u2019s two wires, or invert it in code.<\/p>\n
Pin reference<\/h2>\n
The driver\u2019s wiring is as in Driving DC Motors with an L298N<\/em>. Repeated here for one chassis:<\/p>\n\n\n\nL298N<\/th>\n Connect to<\/th>\n Purpose<\/th>\n<\/tr>\n<\/thead>\n \n\nENA<\/code><\/td>\nUno D10<\/code><\/td>\nLeft speed, PWM, jumper removed<\/td>\n<\/tr>\n \nIN1<\/code><\/td>\nUno D9<\/code><\/td>\nLeft direction<\/td>\n<\/tr>\n \nIN2<\/code><\/td>\nUno D8<\/code><\/td>\nLeft direction<\/td>\n<\/tr>\n \nIN3<\/code><\/td>\nUno D7<\/code><\/td>\nRight direction<\/td>\n<\/tr>\n \nIN4<\/code><\/td>\nUno D6<\/code><\/td>\nRight direction<\/td>\n<\/tr>\n \nENB<\/code><\/td>\nUno D5<\/code><\/td>\nRight speed, PWM, jumper removed<\/td>\n<\/tr>\n \nOUT1<\/code>, OUT2<\/code><\/td>\nLeft motor<\/td>\n Either way round; correct later<\/td>\n<\/tr>\n \nOUT3<\/code>, OUT4<\/code><\/td>\nRight motor<\/td>\n <\/td>\n<\/tr>\n \n+12V<\/code>, GND<\/code><\/td>\nMotor supply, and Uno GND<\/code><\/strong><\/td>\nGrounds joined<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n![\"Two](\"http:\/\/siratek.net\/wp-content\/uploads\/2026\/11\/geared-motor-wheels-wiring.svg\")
Two identical motors do not run at the same speed. Trim it, measure it with encoders, or build something that corrects its own heading.<\/figcaption><\/figure>\nWiring steps<\/h2>\n\n- Solder leads to both motors before mounting them.<\/li>\n
- Screw both motors to the chassis, wheels on, with a castor at the opposite end.<\/li>\n
- Wire the L298N as in its own tutorial: enable jumpers off<\/strong>, six logic wires to the Uno.<\/li>\n
- Motors to
OUT1<\/code>\/OUT2<\/code> and OUT3<\/code>\/OUT4<\/code>.<\/li>\n- Motor supply to
+12V<\/code> and GND<\/code>, and join that ground to the Uno\u2019s GND<\/code><\/strong>.<\/li>\n- Put the robot on a stand<\/strong> so the wheels spin free. It will drive off the bench otherwise, and the first run is the one most likely to go in an unexpected direction.<\/li>\n
- Plug in the USB cable, then the motor supply.<\/li>\n<\/ol>\n
Software and libraries<\/h2>\n
No library is required.<\/p>\n
Minimal working example<\/h2>\n\/\/ Siratek: prove each motor, one at a time, with the wheels off the ground.\n\nconst int enA = 10, in1 = 9, in2 = 8; \/\/ left\nconst int enB = 5, in3 = 7, in4 = 6; \/\/ right\n\nvoid setup() {\n int pins[] = {enA, in1, in2, enB, in3, in4};\n for (int i = 0; i < 6; i++) {\n pinMode(pins[i], OUTPUT);\n }\n Serial.begin(9600);\n Serial.println(\"Siratek: left forward, left back, right forward, right back.\");\n}\n\nvoid leftMotor(int speed) {\n digitalWrite(in1, speed >= 0);\n digitalWrite(in2, speed < 0);\n analogWrite(enA, abs(speed));\n}\n\nvoid rightMotor(int speed) {\n digitalWrite(in3, speed >= 0);\n digitalWrite(in4, speed < 0);\n analogWrite(enB, abs(speed));\n}\n\nvoid loop() {\n Serial.println(\"left forward\");\n leftMotor(200); delay(1500); leftMotor(0); delay(500);\n\n Serial.println(\"left back\");\n leftMotor(-200); delay(1500); leftMotor(0); delay(500);\n\n Serial.println(\"right forward\");\n rightMotor(200); delay(1500); rightMotor(0); delay(500);\n\n Serial.println(\"right back\");\n rightMotor(-200); delay(1500); rightMotor(0); delay(2000);\n}<\/code><\/pre>\nWatch which way each wheel turns when the sketch says \u201cforward\u201d. If one is wrong, swap that motor\u2019s two wires at the terminal block, or swap its two digitalWrite()<\/code> lines. Either is fine; doing it in the wiring keeps the code honest.<\/p>\nDriving, with the trim<\/h3>\n\/\/ Siratek: the two motors, with a correction for their mismatch.\n\n\/\/ Measured, not guessed. See the procedure below.\nconst float LEFT_TRIM = 1.00;\nconst float RIGHT_TRIM = 0.92;\n\n\/\/ Below this, the motors hum instead of turning.\nconst int MINIMUM_SPEED = 70;\n\nvoid drive(int left, int right) {\n left = (int) (left * LEFT_TRIM);\n right = (int) (right * RIGHT_TRIM);\n\n leftMotor(constrain(left, -255, 255));\n rightMotor(constrain(right, -255, 255));\n}\n\nvoid forward(int speed) { drive(speed, speed); }\nvoid backward(int speed) { drive(-speed, -speed); }\nvoid spinLeft(int speed) { drive(-speed, speed); }\nvoid spinRight(int speed){ drive(speed, -speed); }\nvoid halt() { drive(0, 0); }<\/code><\/pre>\nMeasuring the trim<\/h3>\n
Two minutes on the floor, and it replaces a guess with a number.<\/p>\n
\n- Mark a straight line on the floor, two or three metres long.<\/li>\n
- Run
forward(180)<\/code> and let the robot travel the whole length.<\/li>\n- Note which way it veers.<\/li>\n
- Reduce the trim on the side it veers away from<\/strong>, by about 0.05.<\/li>\n
- Repeat until it runs reasonably straight.<\/li>\n<\/ol>\n
Veering left means the right wheel is faster, so lower RIGHT_TRIM<\/code>.<\/p>\nTwo things worth knowing about the result. It is only right at that speed<\/strong>: trim at 180 and the robot will curve at 120. And it changes as the batteries drain, which is one of the reasons encoders exist.<\/p>\nThe starting speed<\/h3>\n
As on the L298N page: at low PWM values the motors hum and do not turn, because the average torque cannot overcome the gearbox friction. On these motors the threshold is often around 60 to 80.<\/p>\n
void startMoving(int speed) {\n drive(255, 255); \/\/ a brief full-power kick\n delay(60);\n drive(speed, speed);\n}<\/code><\/pre>\nFind your own minimum by stepping the value up from a standstill until both wheels turn reliably. Then never ask for less than that from rest.<\/p>\n
Expected result<\/h2>\n
With the wheels off the ground, each motor turning both ways in turn, smoothly, with an audible change as the speed changes.<\/p>\n
On the floor, a robot that drives roughly straight after trimming, turns on the spot when the wheels are driven in opposite directions, and does not reset when it bumps into something.<\/p>\n
A reset on contact is the stall current, and the answer is a better motor supply rather than anything in the sketch.<\/p>\n
Troubleshooting<\/h2>\n
\n\n\nSymptom<\/th>\n Likely cause<\/th>\n Check or fix<\/th>\n<\/tr>\n<\/thead>\n \n\nOne wheel turns the wrong way<\/td>\n Motors face opposite ways<\/td>\n Swap that motor\u2019s two wires<\/td>\n<\/tr>\n \nMotors only run at full speed<\/td>\n ENA<\/code>\/ENB<\/code> jumpers still fitted<\/td>\nRemove them; wire to PWM pins<\/td>\n<\/tr>\n \nNothing moves at all<\/td>\n Motor supply, or grounds not joined<\/td>\n Both, in that order<\/td>\n<\/tr>\n \nRobot resets when it hits something<\/td>\n Stall current, near 1 A each<\/td>\n A supply that holds up, grounds joined<\/td>\n<\/tr>\n \nHums but does not turn from rest<\/td>\n Below the starting duty cycle<\/td>\n Kick at full power briefly<\/td>\n<\/tr>\n \nVeers even after trimming<\/td>\n Trim is speed-specific<\/td>\n Re-trim at the speed you use<\/td>\n<\/tr>\n \nVeers more as the batteries drain<\/td>\n Expected<\/td>\n Encoders, or fresh cells<\/td>\n<\/tr>\n \nWheel slips on the shaft<\/td>\n Not pushed fully on<\/td>\n It is a tight D-shaped fit<\/td>\n<\/tr>\n \nA motor lead came off<\/td>\n The tabs are fragile<\/td>\n Resolder and add hot glue<\/td>\n<\/tr>\n \nWeak, will not climb a slope<\/td>\n L298N drops about 2 V<\/td>\n Supply a couple of volts above the motor rating<\/td>\n<\/tr>\n \nOne motor much slower than the other<\/td>\n Gearbox binding<\/td>\n Run it unloaded and listen<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nNext steps<\/h2>\n\n- Easier first:<\/strong> Driving DC Motors with an L298N<\/em>, which this page assumes.<\/li>\n
- Related products:<\/strong> the four-way tracking sensor, which gives the robot something to follow, and the HC-SR04, for noticing obstacles.<\/li>\n
- Next project:<\/strong> a line following robot, where the constant steering correction means the motor mismatch stops mattering.<\/li>\n<\/ul>\n
Sources and attribution<\/h2>\n
All text, wiring guidance and code in this tutorial are original Siratek work.<\/p>\n
\n- The yellow TT-type gearbox, the dual-sided shaft and the push-fit wheel were read from the Siratek product photographs for item 7406.<\/li>\n
- Driver wiring, the enable jumpers and the bridge voltage drop are as set out in Driving DC Motors with an L298N<\/em>.<\/li>\n<\/ul>\n
Gear ratio, current and speed figures are typical for this motor type rather than from a datasheet for this specific part, and the tutorial gives procedures for measuring the trim and the starting duty cycle rather than asserting values. Siratek product 7406 is one motor and wheel; a driving robot needs two.<\/strong> No third-party tutorial text, diagrams, photographs or code has been reproduced here.<\/p>\n<\/p>\n<\/body>","protected":false},"excerpt":{"rendered":"
A small DC motor with a plastic gearbox on the front and a rubber wheel that pushes on. The gearbox trades the motor's uselessly high speed for the torque needed to actually move something.<\/p>\n","protected":false},"featured_media":0,"template":"","siratek_tutorial_level":[],"class_list":["post-52245","siratek_tutorial","type-siratek_tutorial","status-publish","hentry"],"yoast_head":"\n
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What you are getting<\/h3>\n
The Siratek photographs show the common yellow TT gear motor<\/strong>: a small brushed motor in a metal can, a yellow plastic gearbox, a shaft projecting from each side, and a black rubber tyre on a yellow plastic hub.<\/p>\n Typical figures for this type:<\/p>\n The stall current is the number that matters.<\/strong> Two motors stalled is about 2 A, which is far beyond a USB supply and more than a weak battery pack will hold up under. A robot that resets when it hits a wall is this, not a software fault.<\/p>\n The motor has a shaft on both sides. One takes the wheel; the other is spare, and is there so you can fit an encoder disc if you later want to know how far you have travelled.<\/p>\n Push the wheel on firmly. The hub is a tight fit on a D-shaped shaft and it only goes on one way round.<\/p>\n The terminals are two small metal tabs with no wires attached. Solder leads on before<\/strong> you screw the motor to a chassis, because afterwards the tabs are awkward to reach and the heat is harder to manage.<\/p>\n Keep them short, use stranded wire so they flex, and add a dab of hot glue over the joint: those tabs break off easily if the wire is tugged.<\/p>\n This is the thing that surprises people, so it comes before the wiring.<\/p>\n Give two identical motors the same voltage and the robot curves. Always. The gearboxes differ a little, the brushes differ, the friction differs, and the difference is often ten percent or more.<\/p>\n There are three honest responses:<\/p>\n Trim it in software.<\/strong> Measure how much each motor needs to go straight and apply a correction factor. Simple, free, and only right at one speed and on one surface.<\/p>\n Fit encoders.<\/strong> The spare shaft takes a slotted disc, and an optical sensor counts the slots. Then the sketch knows the actual speed of each wheel and can correct continuously. This is the proper answer and it is a project of its own.<\/p>\n Do not need it to go straight.<\/strong> A line-following robot corrects its heading constantly from the line itself, so the motors never need to match. That is why line following is the natural first robot: the mismatch stops mattering.<\/p>\n The sketch below includes the trim, because it is the first thing anyone needs.<\/p>\n Swapping a motor\u2019s two leads reverses it. Because the two motors face opposite ways on a chassis, one of them will almost certainly need its leads swapped<\/strong> for both wheels to drive the robot in the same direction.<\/p>\n Expect this rather than being puzzled by it: the first time you run both motors forward, one wheel will turn backwards. Swap that motor\u2019s two wires, or invert it in code.<\/p>\n The driver\u2019s wiring is as in Driving DC Motors with an L298N<\/em>. Repeated here for one chassis:<\/p>\n No library is required.<\/p>\n Watch which way each wheel turns when the sketch says \u201cforward\u201d. If one is wrong, swap that motor\u2019s two wires at the terminal block, or swap its two Two minutes on the floor, and it replaces a guess with a number.<\/p>\n Veering left means the right wheel is faster, so lower Two things worth knowing about the result. It is only right at that speed<\/strong>: trim at 180 and the robot will curve at 120. And it changes as the batteries drain, which is one of the reasons encoders exist.<\/p>\n As on the L298N page: at low PWM values the motors hum and do not turn, because the average torque cannot overcome the gearbox friction. On these motors the threshold is often around 60 to 80.<\/p>\n Find your own minimum by stepping the value up from a standstill until both wheels turn reliably. Then never ask for less than that from rest.<\/p>\n With the wheels off the ground, each motor turning both ways in turn, smoothly, with an audible change as the speed changes.<\/p>\n On the floor, a robot that drives roughly straight after trimming, turns on the spot when the wheels are driven in opposite directions, and does not reset when it bumps into something.<\/p>\n A reset on contact is the stall current, and the answer is a better motor supply rather than anything in the sketch.<\/p>\n All text, wiring guidance and code in this tutorial are original Siratek work.<\/p>\n Gear ratio, current and speed figures are typical for this motor type rather than from a datasheet for this specific part, and the tutorial gives procedures for measuring the trim and the starting duty cycle rather than asserting values. Siratek product 7406 is one motor and wheel; a driving robot needs two.<\/strong> No third-party tutorial text, diagrams, photographs or code has been reproduced here.<\/p>\n <\/p>\n<\/body>","protected":false},"excerpt":{"rendered":" A small DC motor with a plastic gearbox on the front and a rubber wheel that pushes on. The gearbox trades the motor's uselessly high speed for the torque needed to actually move something.<\/p>\n","protected":false},"featured_media":0,"template":"","siratek_tutorial_level":[],"class_list":["post-52245","siratek_tutorial","type-siratek_tutorial","status-publish","hentry"],"yoast_head":"\n\n\n
\n \n<\/th>\n <\/th>\n<\/tr>\n<\/thead>\n \n Supply<\/td>\n 3 to 6 V<\/td>\n<\/tr>\n \n Gear ratio<\/td>\n about 1:48<\/td>\n<\/tr>\n \n Free-running current<\/td>\n roughly 150 to 200 mA each<\/td>\n<\/tr>\n \n Stall current<\/strong><\/td>\n close to 1 A each<\/strong><\/td>\n<\/tr>\n \n Output speed at 6 V<\/td>\n very roughly 200 revolutions per minute<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n The shaft goes through<\/h3>\n
Solder the leads before mounting anything<\/h3>\n
Two motors will not run at the same speed<\/h3>\n
Which way is forward<\/h3>\n
Pin reference<\/h2>\n
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\n \nL298N<\/th>\n Connect to<\/th>\n Purpose<\/th>\n<\/tr>\n<\/thead>\n \n ENA<\/code><\/td>\nUno D10<\/code><\/td>\nLeft speed, PWM, jumper removed<\/td>\n<\/tr>\n \n IN1<\/code><\/td>\nUno D9<\/code><\/td>\nLeft direction<\/td>\n<\/tr>\n \n IN2<\/code><\/td>\nUno D8<\/code><\/td>\nLeft direction<\/td>\n<\/tr>\n \n IN3<\/code><\/td>\nUno D7<\/code><\/td>\nRight direction<\/td>\n<\/tr>\n \n IN4<\/code><\/td>\nUno D6<\/code><\/td>\nRight direction<\/td>\n<\/tr>\n \n ENB<\/code><\/td>\nUno D5<\/code><\/td>\nRight speed, PWM, jumper removed<\/td>\n<\/tr>\n \n OUT1<\/code>, OUT2<\/code><\/td>\nLeft motor<\/td>\n Either way round; correct later<\/td>\n<\/tr>\n \n OUT3<\/code>, OUT4<\/code><\/td>\nRight motor<\/td>\n <\/td>\n<\/tr>\n \n +12V<\/code>, GND<\/code><\/td>\nMotor supply, and Uno GND<\/code><\/strong><\/td>\nGrounds joined<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Wiring steps<\/h2>\n
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OUT1<\/code>\/OUT2<\/code> and OUT3<\/code>\/OUT4<\/code>.<\/li>\n+12V<\/code> and GND<\/code>, and join that ground to the Uno\u2019s GND<\/code><\/strong>.<\/li>\nSoftware and libraries<\/h2>\n
Minimal working example<\/h2>\n
\/\/ Siratek: prove each motor, one at a time, with the wheels off the ground.\n\nconst int enA = 10, in1 = 9, in2 = 8; \/\/ left\nconst int enB = 5, in3 = 7, in4 = 6; \/\/ right\n\nvoid setup() {\n int pins[] = {enA, in1, in2, enB, in3, in4};\n for (int i = 0; i < 6; i++) {\n pinMode(pins[i], OUTPUT);\n }\n Serial.begin(9600);\n Serial.println(\"Siratek: left forward, left back, right forward, right back.\");\n}\n\nvoid leftMotor(int speed) {\n digitalWrite(in1, speed >= 0);\n digitalWrite(in2, speed < 0);\n analogWrite(enA, abs(speed));\n}\n\nvoid rightMotor(int speed) {\n digitalWrite(in3, speed >= 0);\n digitalWrite(in4, speed < 0);\n analogWrite(enB, abs(speed));\n}\n\nvoid loop() {\n Serial.println(\"left forward\");\n leftMotor(200); delay(1500); leftMotor(0); delay(500);\n\n Serial.println(\"left back\");\n leftMotor(-200); delay(1500); leftMotor(0); delay(500);\n\n Serial.println(\"right forward\");\n rightMotor(200); delay(1500); rightMotor(0); delay(500);\n\n Serial.println(\"right back\");\n rightMotor(-200); delay(1500); rightMotor(0); delay(2000);\n}<\/code><\/pre>\ndigitalWrite()<\/code> lines. Either is fine; doing it in the wiring keeps the code honest.<\/p>\nDriving, with the trim<\/h3>\n
\/\/ Siratek: the two motors, with a correction for their mismatch.\n\n\/\/ Measured, not guessed. See the procedure below.\nconst float LEFT_TRIM = 1.00;\nconst float RIGHT_TRIM = 0.92;\n\n\/\/ Below this, the motors hum instead of turning.\nconst int MINIMUM_SPEED = 70;\n\nvoid drive(int left, int right) {\n left = (int) (left * LEFT_TRIM);\n right = (int) (right * RIGHT_TRIM);\n\n leftMotor(constrain(left, -255, 255));\n rightMotor(constrain(right, -255, 255));\n}\n\nvoid forward(int speed) { drive(speed, speed); }\nvoid backward(int speed) { drive(-speed, -speed); }\nvoid spinLeft(int speed) { drive(-speed, speed); }\nvoid spinRight(int speed){ drive(speed, -speed); }\nvoid halt() { drive(0, 0); }<\/code><\/pre>\nMeasuring the trim<\/h3>\n
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forward(180)<\/code> and let the robot travel the whole length.<\/li>\nRIGHT_TRIM<\/code>.<\/p>\nThe starting speed<\/h3>\n
void startMoving(int speed) {\n drive(255, 255); \/\/ a brief full-power kick\n delay(60);\n drive(speed, speed);\n}<\/code><\/pre>\nExpected result<\/h2>\n
Troubleshooting<\/h2>\n
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\n \nSymptom<\/th>\n Likely cause<\/th>\n Check or fix<\/th>\n<\/tr>\n<\/thead>\n \n One wheel turns the wrong way<\/td>\n Motors face opposite ways<\/td>\n Swap that motor\u2019s two wires<\/td>\n<\/tr>\n \n Motors only run at full speed<\/td>\n ENA<\/code>\/ENB<\/code> jumpers still fitted<\/td>\nRemove them; wire to PWM pins<\/td>\n<\/tr>\n \n Nothing moves at all<\/td>\n Motor supply, or grounds not joined<\/td>\n Both, in that order<\/td>\n<\/tr>\n \n Robot resets when it hits something<\/td>\n Stall current, near 1 A each<\/td>\n A supply that holds up, grounds joined<\/td>\n<\/tr>\n \n Hums but does not turn from rest<\/td>\n Below the starting duty cycle<\/td>\n Kick at full power briefly<\/td>\n<\/tr>\n \n Veers even after trimming<\/td>\n Trim is speed-specific<\/td>\n Re-trim at the speed you use<\/td>\n<\/tr>\n \n Veers more as the batteries drain<\/td>\n Expected<\/td>\n Encoders, or fresh cells<\/td>\n<\/tr>\n \n Wheel slips on the shaft<\/td>\n Not pushed fully on<\/td>\n It is a tight D-shaped fit<\/td>\n<\/tr>\n \n A motor lead came off<\/td>\n The tabs are fragile<\/td>\n Resolder and add hot glue<\/td>\n<\/tr>\n \n Weak, will not climb a slope<\/td>\n L298N drops about 2 V<\/td>\n Supply a couple of volts above the motor rating<\/td>\n<\/tr>\n \n One motor much slower than the other<\/td>\n Gearbox binding<\/td>\n Run it unloaded and listen<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Next steps<\/h2>\n
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Sources and attribution<\/h2>\n
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