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Hi guys,

So we have built a vehicle. It is controlled via an arduino and a motor. I will find the specifications for it. We have an 30A ESC for it as well. WE have used an 1800maH 7.2V nimh battery to power it. We have code for it and the vehicle goes pretty fast. However, we come to the problem where the vehicle becomes severely inconsistent. The battery would be at full charge and in the 1st attempt it would travel about 7 meters, the second attempt it would travel around 9 meters. The last time attempt it somehow went at full speed and crossed over 16 meters and crashed into a wall. So we are going to fix the broken parts. I would really like to listen to ideas that you guys will provide on why this could be happening? It is not the battery because we checked with a multimeter and it was still at full charge. Do you guys have possible solutions? Thanks!

How is the vehicle determining when to stop?

The motor is delayed for a set amount of time. It was the same code run over again. The delay was set to 1250 milliseconds which means 1.25 seconds. However, the vehicle does roll after the 1.25 seconds but during those tries it didnt look like the motor was running for a constant 1.25 seconds; it seemed too random and unpredictable

harik2000 wrote:The motor is delayed for a set amount of time. It was the same code run over again. The delay was set to 1250 milliseconds which means 1.25 seconds. However, the vehicle does roll after the 1.25 seconds but during those tries it didnt look like the motor was running for a constant 1.25 seconds; it seemed too random and unpredictable

Ok so first of all the ESC has a voltage regulator which makes sure that it gives the motor the same power regardless of charge. Your problem is that you are using brakes based on time which are very very unreliable. You need something that monitors the position of the vehicle (wingnut brake, encoder, etc) and then stop it based on that. In theory time based brakes should work but they dont because at such high speeds there is a lot of error and inconsistency.

Oneof the biggest factors with going fast are your wheels. It is likely the majority of your problems will stem from skid or imbalanced wheel alignment